Publish

- @now/build-utils@0.9.11
 - @now/go@0.5.8
 - @now/next@0.5.9
 - @now/node@0.12.4
 - @now/python@0.2.14
 - @now/ruby@0.1.4
 - @now/static-build@0.9.5

.circleci/config.yml

@@ -29,14 +29,8 @@ jobs:
       - run:
           name: Tests and Coverage
           command: yarn test-coverage
-      - run:
-          name: Potentially save npm token
-          command: "([[ ! -z $NPM_TOKEN ]] && echo \"//registry.npmjs.org/:_authToken=$NPM_TOKEN\" >> ~/.npmrc) || echo \"Did not write npm token\""
-      - run:
-          name: Potentially publish releases to npm
-          command: ./.circleci/publish.sh
 workflows:
   version: 2
-  build-and-deploy:
+  build-and-test:
     jobs:
       - build

.circleci/publish.sh

@@ -1,6 +1,13 @@
 #!/bin/bash
 set -euo pipefail
 
+if [ -z "$NPM_TOKEN" ]; then
+  echo "NPM_TOKEN not found. Did you forget to assign the GitHub Action secret?"
+  exit 1
+fi
+
+echo "//registry.npmjs.org/:_authToken=$NPM_TOKEN" >> ~/.npmrc
+
 if [ ! -e ~/.npmrc ]; then
   echo "~/.npmrc file does not exist, skipping publish"
   exit 0
@@ -21,4 +28,7 @@ else
   echo "Publishing stable release"
 fi
 
+# Sometimes this is a false alarm and blocks publish
+git checkout yarn.lock
+
 yarn run lerna publish from-git $npm_tag --yes

.editorconfig

@@ -1,30 +1,41 @@
 root = true
 
 [*]
-indent_style = tab
-indent_size = 4
-tab_width = 4
 end_of_line = lf
 charset = utf-8
 trim_trailing_whitespace = true
 insert_final_newline = true
 
-[{*.json,*.json.example,*.gyp,*.yml}]
+[{*.json,*.json.example,*.gyp,*.yml,*.yaml,*.workflow}]
 indent_style = space
 indent_size = 2
 
-[*.py]
+[{*.py,*.asm}]
 indent_style = space
+
+[*.py]
 indent_size = 4
 
+[*.asm]
+indent_size = 8
+
 [*.md]
 trim_trailing_whitespace = false
+indent_style = space
+indent_size = 2
 
-# Ideal settings - some plugins might support these.
+# Ideal settings - some plugins might support these
-[*.js]
+[*.js,*.jsx,*.ts,*.tsx]
 quote_type = single
+indent_style = space
+indent_size = 2
 
-[{*.c,*.cc,*.h,*.hh,*.cpp,*.hpp,*.m,*.mm,*.mpp,*.js,*.java,*.go,*.rs,*.php,*.ng,*.jsx,*.ts,*.d,*.cs,*.swift}]
+[{*.c,*.cc,*.h,*.hh,*.cpp,*.hpp,*.m,*.mm,*.mpp,*.java,*.go,*.rs,*.php,*.ng,*.d,*.cs,*.swift}]
+indent_style = tab
+indent_size = 4
+tab_width = 4
+
+[{*.c,*.cc,*.h,*.hh,*.cpp,*.hpp,*.m,*.mm,*.mpp,*.js,*.java,*.go,*.rs,*.php,*.ng,*.jsx,*.ts,*.tsx,*.d,*.cs,*.swift}]
 curly_bracket_next_line = false
 spaces_around_operators = true
 spaces_around_brackets = outside

.eslintignore

@@ -3,8 +3,14 @@
 /**/node_modules/*
 /packages/now-go/go/*
 /packages/now-build-utils/dist/*
+/packages/now-build-utils/src/*.js
+/packages/now-build-utils/src/fs/*.js
 /packages/now-node/dist/*
 /packages/now-next/dist/*
 /packages/now-node-bridge/*
-/packages/now-python/*
+/packages/now-python/dist/*
-/packages/now-optipng/dist/*
+/packages/now-go/*
+/packages/now-ruby/dist/*
+/packages/now-static-build/dist/*
+/packages/now-static-build/test/fixtures/**
+/packages/now-routing-utils/dist/*

.github/CODEOWNERS

@@ -0,0 +1,13 @@
+# Documentation
+# https://help.github.com/en/articles/about-code-owners
+
+*                         @styfle
+/packages/now-build-utils @styfle @AndyBitz
+/packages/now-node        @styfle @tootallnate @lucleray
+/packages/now-node-bridge @styfle @tootallnate @lucleray
+/packages/now-next        @timer
+/packages/now-go          @styfle @sophearak
+/packages/now-python      @styfle @sophearak
+/packages/now-ruby        @styfle @coetry @nathancahill
+/packages/now-static-build @styfle @AndyBitz
+/packages/now-routing-utils @dav-is

.github/main.workflow

@@ -0,0 +1,76 @@
+workflow "Canary publish" {
+  on = "push"
+  resolves = ["3. Canary yarn run publish"]
+}
+
+action "0. Canary filter" {
+  uses = "actions/bin/filter@3c0b4f0e63ea54ea5df2914b4fabf383368cd0da"
+  args = "branch canary"
+}
+
+action "0. Canary PR not deleted" {
+  uses = "actions/bin/filter@3c0b4f0e63ea54ea5df2914b4fabf383368cd0da"
+  needs = ["0. Canary filter"]
+  args = "not deleted"
+}
+
+action "1. Canary yarn install" {
+  uses = "actions/npm@59b64a598378f31e49cb76f27d6f3312b582f680"
+  needs = ["0. Canary PR not deleted"]
+  runs = "yarn"
+  args = "--pure-lockfile install"
+}
+
+action "2. Canary yarn run build" {
+  uses = "actions/npm@59b64a598378f31e49cb76f27d6f3312b582f680"
+  needs = ["1. Canary yarn install"]
+  runs = "yarn"
+  args = "--pure-lockfile run build"
+}
+
+action "3. Canary yarn run publish" {
+  uses = "actions/npm@59b64a598378f31e49cb76f27d6f3312b582f680"
+  needs = ["2. Canary yarn run build"]
+  runs = "yarn"
+  args = "--pure-lockfile run publish-from-github"
+  secrets = ["NPM_TOKEN"]
+}
+
+
+workflow "Master publish" {
+  on = "push"
+  resolves = ["3. Master yarn run publish"]
+}
+
+action "0. Master filter" {
+  uses = "actions/bin/filter@3c0b4f0e63ea54ea5df2914b4fabf383368cd0da"
+  args = "branch master"
+}
+
+action "0. Master PR not deleted" {
+  uses = "actions/bin/filter@3c0b4f0e63ea54ea5df2914b4fabf383368cd0da"
+  needs = ["0. Master filter"]
+  args = "not deleted"
+}
+
+action "1. Master yarn install" {
+  uses = "actions/npm@59b64a598378f31e49cb76f27d6f3312b582f680"
+  needs = ["0. Master PR not deleted"]
+  runs = "yarn"
+  args = "--pure-lockfile install"
+}
+
+action "2. Master yarn run build" {
+  uses = "actions/npm@59b64a598378f31e49cb76f27d6f3312b582f680"
+  needs = ["1. Master yarn install"]
+  runs = "yarn"
+  args = "--pure-lockfile run build"
+}
+
+action "3. Master yarn run publish" {
+  uses = "actions/npm@59b64a598378f31e49cb76f27d6f3312b582f680"
+  needs = ["2. Master yarn run build"]
+  runs = "yarn"
+  args = "--pure-lockfile run publish-from-github"
+  secrets = ["NPM_TOKEN"]
+}

.gitignore

@@ -1,4 +1,6 @@
 node_modules
 tmp
 target/
-.next
+.next
+coverage
+*.tgz

.prettierrc.json

@@ -1,4 +0,0 @@
-{
-  "singleQuote": true,
-  "trailingComma": "es5"
-}

.vscode/settings.json

@@ -1,3 +0,0 @@
-{
-  "eslint.enable": false
-}

CODE_OF_CONDUCT.md

@@ -0,0 +1,74 @@
+## Code of Conduct
+
+### Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, gender identity and expression, level of experience,
+nationality, personal appearance, race, religion, or sexual identity and
+orientation.
+
+### Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+- Using welcoming and inclusive language
+- Being respectful of differing viewpoints and experiences
+- Gracefully accepting constructive criticism
+- Focusing on what is best for the community
+- Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+- The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+- Trolling, insulting/derogatory comments, and personal or political attacks
+- Public or private harassment
+- Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+- Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+### Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+### Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+### Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at [abuse@zeit.co](mailto:abuse@zeit.co). All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+### Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at [http://contributor-covenant.org/version/1/4][version]
+
+[homepage]: http://contributor-covenant.org
+[version]: http://contributor-covenant.org/version/1/4/

CONTRIBUTING.md

@@ -0,0 +1,85 @@
+# Contributing
+
+When contributing to this repository, please first discuss the change you wish to make via issue or [spectrum](https://spectrum.chat/zeit) with the owners of this repository before submitting a Pull Request.
+
+Please read our [code of conduct](CODE_OF_CONDUCT.md) and follow it in all your interactions with the project.
+
+## Local development
+
+This project is configured in a monorepo pattern where one repo contains multiple npm packages. Dependencies are installed and managed with `yarn`, not `npm` CLI.
+
+To get started, execute the following:
+
+```
+git clone https://github.com/zeit/now-builders
+yarn install
+yarn bootstrap
+yarn build
+yarn lint
+yarn test
+```
+
+Make sure all the tests pass before making changes.
+
+## Verifying your change
+
+Once you are done with your changes (we even suggest doing it along the way ), make sure all the test still run by running
+
+```
+yarn build && yarn test
+```
+
+from the root of the project.
+
+If any test fails, make sure to fix it along with your changes. See [Interpreting test errors](#Interpreting-test-errors) for more information about how the tests are executed, especially the integration tests.
+
+## Pull Request Process
+
+Once you are confident that your changes work properly, open a pull request on the main repository.
+
+The pull request will be reviewed by the maintainers and the tests will be checked by our continuous integration platform.
+
+## Interpreting test errors
+
+There are 2 kinds of tests in this repository – Unit tests and Integration tests.
+
+Unit tests are run locally with `jest` and execute quickly because they are testing the smallest units of code.
+
+### Integration tests
+
+Integration tests create deployments to your ZEIT account using the `test` project name. After each test is deployed, the `probes` key is used to check if the response is the expected value. If the value doesn't match, you'll see a message explaining the difference. If the deployment failed to build, you'll see a more generic message like the following:
+
+```
+[Error: Fetched page https://test-8ashcdlew.now.sh/root.js does not contain hello Root!. Instead it contains An error occurred with this application.
+
+    NO_STATUS_CODE_FRO Response headers:
+       cache-control=s-maxage=0
+      connection=close
+      content-type=text/plain; charset=utf-8
+      date=Wed, 19 Jun 2019 18:01:37 GMT
+      server=now
+      strict-transport-security=max-age=63072000
+      transfer-encoding=chunked
+      x-now-id=iad1:hgtzj-1560967297876-44ae12559f95
+      x-now-trace=iad1]
+```
+
+In such cases you can visit the URL of the failed deployment and append `/_logs` so see the build error. In the case above, that would be https://test-8ashcdlew.now.sh/_logs
+
+The logs of this deployment will contain the actual error which may help you to understand what went wrong.
+
+### @zeit/ncc integration
+
+Some of the builders use `@zeit/ncc` to bundle files before deployment. If you suspect an error with the bundling mechanism, you can run the `ncc` CLI with a couple modifications to the test.
+
+For example if an error occurred in `now-node/test/fixtures/08-assets`
+
+```
+cd packages/now-node/test/fixtures/08-assets
+yarn install
+echo 'require("http").createServer(module.exports).listen(3000)' >> index.js
+npx @zeit/ncc@0.20.1 build index.js --source-map
+node dist
+```
+
+This will compile the test with the specific version of `ncc` and run the resulting file. If it fails here, then there is likely a bug in `ncc` and not the Builder.

DEVELOPING_A_BUILDER.md

@@ -0,0 +1,447 @@
+# Builders Developer Reference
+
+The following page is a reference for how to create a Builder using the available Builder's API.
+
+A Builder is an npm module that exposes a `build` function and optionally an `analyze` function and `prepareCache` function.
+Official Builders are published to [npmjs.com](https://npmjs.com) as a package and referenced in the `use` property of the `now.json` configuration file.
+However, the `use` property will work with any [npm install argument](https://docs.npmjs.com/cli/install) such as a git repo url which is useful for testing your Builder.
+
+See the [Builders Documentation](https://zeit.co/docs/v2/advanced/builders) to view example usage.
+
+## Builder Exports
+
+### `version`
+
+A **required** exported constant that decides which version of the Builder API to use.
+
+The latest and suggested version is `2`.
+
+### `analyze`
+
+An **optional** exported function that returns a unique fingerprint used for the purpose of [build de-duplication](https://zeit.co/docs/v2/advanced/concepts/immutability#deduplication-algorithm). If the `analyze` function is not supplied, a random fingerprint is assigned to each build.
+
+```js
+export analyze({
+  files: Files,
+  entrypoint: String,
+  workPath: String,
+  config: Object
+}) : String fingerprint
+```
+
+If you are using TypeScript, you should use the following types:
+
+```ts
+import { AnalyzeOptions } from '@now/build-utils'
+
+export analyze(options: AnalyzeOptions) {
+  return 'fingerprint goes here'
+}
+```
+
+### `build`
+
+A **required** exported function that returns a [Files](#files) data structure that contains the Build outputs, which can be a [Static File](#file) or a [Serverless Function](#serverless-function).
+
+What's a Serverless Function? Read about [Serverless Function concepts](https://zeit.co/docs/v2/deployments/concepts/lambdas) to learn more.
+
+```js
+build({
+  files: Files,
+  entrypoint: String,
+  workPath: String,
+  config: Object,
+  meta?: {
+    isDev?: Boolean,
+    requestPath?: String,
+    filesChanged?: Array<String>,
+    filesRemoved?: Array<String>
+  }
+}) : {
+  watch: Array<String>,
+  output: Files output,
+  routes: Object
+}
+```
+
+If you are using TypeScript, you should use the following types:
+
+```ts
+import { BuildOptions } from '@now/build-utils'
+
+export build(options: BuildOptions) {
+  // Build the code here
+
+  return {
+    output: {
+      'path-to-file': File,
+      'path-to-lambda': Lambda
+    },
+    watch: [],
+    routes: {}
+  }
+}
+```
+
+### `prepareCache`
+
+An **optional** exported function that is equivalent to [`build`](#build), but it executes the instructions necessary to prepare a cache for the next run.
+
+```js
+prepareCache({
+  files: Files,
+  entrypoint: String,
+  workPath: String,
+  cachePath: String,
+  config: Object
+}) : Files cacheOutput
+```
+
+If you are using TypeScript, you can import the types for each of these functions by using the following:
+
+```ts
+import { PrepareCacheOptions } from '@now/build-utils'
+
+export prepareCache(options: PrepareCacheOptions) {
+  return { 'path-to-file': File }
+}
+```
+
+### `shouldServe`
+
+An **optional** exported function that is only used by `now dev` in [Now CLI](https:///download) and indicates whether a [Builder](https://zeit.co/docs/v2/advanced/builders) wants to be responsible for building a certain request path.
+
+```js
+shouldServe({
+  entrypoint: String,
+  files: Files,
+  config: Object,
+  requestPath: String,
+  workPath: String
+}) : Boolean
+```
+
+If you are using TypeScript, you can import the types for each of these functions by using the following:
+
+```ts
+import { ShouldServeOptions } from '@now/build-utils'
+
+export shouldServe(options: ShouldServeOptions) {
+  return Boolean
+}
+```
+
+If this method is not defined, Now CLI will default to [this function](https://github.com/zeit/now-builders/blob/52994bfe26c5f4f179bdb49783ee57ce19334631/packages/now-build-utils/src/should-serve.ts).
+
+### Builder Options
+
+The exported functions [`analyze`](#analyze), [`build`](#build), and [`prepareCache`](#preparecache) receive one argument with the following properties.
+
+**Properties:**
+
+- `files`: All source files of the project as a [Files](#files) data structure.
+- `entrypoint`: Name of entrypoint file for this particular build job. Value `files[entrypoint]` is guaranteed to exist and be a valid [File](#files) reference. `entrypoint` is always a discrete file and never a glob, since globs are expanded into separate builds at deployment time.
+- `workPath`: A writable temporary directory where you are encouraged to perform your build process. This directory will be populated with the restored cache from the previous run (if any) for [`analyze`](#analyze) and [`build`](#build).
+- `cachePath`: A writable temporary directory where you can build a cache for the next run. This is only passed to `prepareCache`.
+- `config`: An arbitrary object passed from by the user in the [Build definition](#defining-the-build-step) in `now.json`.
+
+## Example: html-minifier
+
+Let's walk through what it takes to create a simple builder that takes in a HTML source file and yields a minified HTML static file as its build output.
+
+While this is a very simple builder, the approach demonstrated here can be used to return anything: one or more static files and/or one or more lambdas.
+
+## Setting up the module
+
+### Defining the analyze step
+
+The `analyze` hook is optional. Its goal is to give the developer a tool to avoid wasting time _re-computing a build_ that has already occurred.
+
+The return value of `analyze` is a _fingerprint_: a simple string that uniquely identifies the build process.
+
+If `analyze` is not specified, its behavior is to use as the fingerprint the combined checksums of **all the files in the same directory level as the entrypoint**. This is a default that errs on making sure that we re-execute builds when files _other than the entrypoint_ (like dependencies, manifest files, etc) have changed.
+
+For our `html-minify` example, we know that HTML files don't have dependencies. Therefore, our analyze step can just return the `digest` of the entrypoint.
+
+Our `index.js` file looks as follows:
+
+```js
+exports.analyze = function({ files, entrypoint }) {
+  return files[entrypoint].digest
+}
+```
+
+This means that we will only re-minify and re-create the build output _only if the file contents (and therefore its digest) change._
+
+### Defining the build step
+
+Your module will need some utilities to manipulate the data structures we pass you, create new ones and alter the filesystem.
+
+To that end, we expose our API as part of a `@now/build-utils` package. This package is always loaded on your behalf, so make sure it's only included as `peerDependencies` in your `package.json`.
+
+Builders can include dependencies of their liking:
+
+```js
+const htmlMinifier = require('html-minifier')
+
+exports.version = 2
+
+exports.analyze = ({ files, entrypoint }) => files[entrypoint].digest
+
+exports.build = async ({ files, entrypoint, config }) => {
+  const stream = files[entrypoint].toStream()
+  const options = Object.assign({}, config || {})
+  const { data } = await FileBlob.fromStream({ stream })
+  const content = data.toString()
+  const minified = htmlMinifier(content, options)
+  const result = new FileBlob({ data: minified })
+
+  return {
+    output: {
+      [entrypoint]: result
+    },
+    watch: [],
+    routes: {}
+  }
+}
+```
+
+### Defining a `prepareCache` step
+
+If our builder had performed work that could be re-used in the next build invocation, we could define a `prepareCache` step.
+
+In this case, there are not intermediate artifacts that we can cache, and our `analyze` step already takes care of caching the full output based on the fingerprint of the input.
+
+## Technical Details
+
+### Execution Context
+
+A [Serverless Function](https://zeit.co/docs/v2/advanced/concepts/lambdas) is created where the builder logic is executed. The lambda is run using the Node.js 8 runtime. A brand new sandbox is created for each deployment, for security reasons. The sandbox is cleaned up between executions to ensure no lingering temporary files are shared from build to build.
+
+All the APIs you export ([`analyze`](#analyze), [`build`](#build) and [`prepareCache`](#preparecache)) are not guaranteed to be run in the same process, but the filesystem we expose (e.g.: `workPath` and the results of calling [`getWriteableDirectory`](#getWriteableDirectory) ) is retained.
+
+If you need to share state between those steps, use the filesystem.
+
+### Directory and Cache Lifecycle
+
+When a new build is created, we pre-populate the `workPath` supplied to `analyze` with the results of the `prepareCache` step of the previous build.
+
+The `analyze` step can modify that directory, and it will not be re-created when it's supplied to `build` and `prepareCache`.
+
+To learn how the cache key is computed and invalidated, refer to the [overview](https://zeit.co/docs/v2/advanced/builders#technical-details).
+
+### Accessing Environment and Secrets
+
+The env and secrets specified by the user as `build.env` are passed to the builder process. This means you can access user env via `process.env` in Node.js.
+
+### Utilities as peerDependencies
+
+When you publish your builder to npm, make sure to not specify `@now/build-utils` (as seen below in the API definitions) as a dependency, but rather as part of `peerDependencies`.
+
+## Types
+
+### `Files`
+
+```ts
+import { File } from '@now/build-utils'
+type Files = { [filePath: string]: File }
+```
+
+This is an abstract type that is implemented as a plain [JavaScript Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object). It's helpful to think of it as a virtual filesystem representation.
+
+When used as an input, the `Files` object will only contain `FileRefs`. When `Files` is an output, it may consist of `Lambda` (Serverless Functions) types as well as `FileRefs`.
+
+An example of a valid output `Files` object is:
+
+```json
+{
+  "index.html": FileRef,
+  "api/index.js": Lambda
+}
+```
+
+### `File`
+
+This is an abstract type that can be imported if you are using TypeScript.
+
+```ts
+import { File } from '@now/build-utils'
+```
+
+Valid `File` types include:
+
+- [`FileRef`](#fileref)
+- [`FileFsRef`](#filefsref)
+- [`FileBlob`](#fileblob)
+
+### `FileRef`
+
+```ts
+import { FileRef } from '@now/build-utils'
+```
+
+This is a [JavaScript class](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes) that represents an abstract file instance stored in our platform, based on the file identifier string (its checksum). When a `Files` object is passed as an input to `analyze` or `build`, all its values will be instances of `FileRef`.
+
+**Properties:**
+
+- `mode : Number` file mode
+- `digest : String` a checksum that represents the file
+
+**Methods:**
+
+- `toStream() : Stream` creates a [Stream](https://nodejs.org/api/stream.html) of the file body
+
+### `FileFsRef`
+
+```ts
+import { FileFsRef } from '@now/build-utils'
+```
+
+This is a [JavaScript class](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes) that represents an abstract instance of a file present in the filesystem that the build process is executing in.
+
+**Properties:**
+
+- `mode : Number` file mode
+- `fsPath : String` the absolute path of the file in file system
+
+**Methods:**
+
+- `static async fromStream({ mode : Number, stream : Stream, fsPath : String }) : FileFsRef` creates an instance of a [FileFsRef](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object) from `Stream`, placing file at `fsPath` with `mode`
+- `toStream() : Stream` creates a [Stream](https://nodejs.org/api/stream.html) of the file body
+
+### `FileBlob`
+
+```ts
+import { FileBlob } from '@now/build-utils'
+```
+
+This is a [JavaScript class](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes) that represents an abstract instance of a file present in memory.
+
+**Properties:**
+
+- `mode : Number` file mode
+- `data : String | Buffer` the body of the file
+
+**Methods:**
+
+- `static async fromStream({ mode : Number, stream : Stream }) :FileBlob` creates an instance of a [FileBlob](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object) from [`Stream`](https://nodejs.org/api/stream.html) with `mode`
+- `toStream() : Stream` creates a [Stream](https://nodejs.org/api/stream.html) of the file body
+
+### `Lambda`
+
+```ts
+import { Lambda } from '@now/build-utils'
+```
+
+This is a [JavaScript class](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes), called a Serverless Function, that can be created by supplying `files`, `handler`, `runtime`, and `environment` as an object to the [`createLambda`](#createlambda) helper. The instances of this class should not be created directly. Instead use a call to [`createLambda`](#createlambda).
+
+**Properties:**
+
+- `files : Files` the internal filesystem of the lambda
+- `handler : String` path to handler file and (optionally) a function name it exports
+- `runtime : LambdaRuntime` the name of the lambda runtime
+- `environment : Object` key-value map of handler-related (aside of those passed by user) environment variables
+
+### `LambdaRuntime`
+
+This is an abstract enumeration type that is implemented by one of the following possible `String` values:
+
+- `nodejs10.x`
+- `nodejs8.10`
+- `go1.x`
+- `java-1.8.0-openjdk`
+- `python3.6`
+- `python2.7`
+- `dotnetcore2.1`
+- `dotnetcore2.0`
+- `dotnetcore1.0`
+
+## JavaScript API
+
+The following is exposed by `@now/build-utils` to simplify the process of writing Builders, manipulating the file system, using the above types, etc.
+
+### `createLambda`
+
+Signature: `createLambda(Object spec) : Lambda`
+
+```ts
+import { createLambda } from '@now/build-utils'
+```
+
+Constructor for the [`Lambda`](#lambda) type.
+
+```js
+const { createLambda, FileBlob } = require('@now/build-utils')
+await createLambda({
+  runtime: 'nodejs8.10',
+  handler: 'index.main',
+  files: {
+    'index.js': new FileBlob({ data: 'exports.main = () => {}' })
+  }
+})
+```
+
+### `download`
+
+Signature: `download() : Files`
+
+```ts
+import { download } from '@now/build-utils'
+```
+
+This utility allows you to download the contents of a [`Files`](#files) data structure, therefore creating the filesystem represented in it.
+
+Since `Files` is an abstract way of representing files, you can think of `download` as a way of making that virtual filesystem _real_.
+
+If the **optional** `meta` property is passed (the argument for [build](#build)), only the files that have changed are downloaded. This is decided using `filesRemoved` and `filesChanged` inside that object.
+
+```js
+await download(files, workPath, meta)
+```
+
+### `glob`
+
+Signature: `glob() : Files`
+
+```ts
+import { glob } from '@now/build-utils'
+```
+
+This utility allows you to _scan_ the filesystem and return a [`Files`](#files) representation of the matched glob search string. It can be thought of as the reverse of [`download`](#download).
+
+The following trivial example downloads everything to the filesystem, only to return it back (therefore just re-creating the passed-in [`Files`](#files)):
+
+```js
+const { glob, download } = require('@now/build-utils')
+
+exports.build = ({ files, workPath }) => {
+  await download(files, workPath)
+  return glob('**', workPath)
+}
+```
+
+### `getWriteableDirectory`
+
+Signature: `getWriteableDirectory() : String`
+
+```ts
+import { getWriteableDirectory } from '@now/build-utils'
+```
+
+In some occasions, you might want to write to a temporary directory.
+
+### `rename`
+
+Signature: `rename(Files) : Files`
+
+```ts
+import { rename } from '@now/build-utils'
+```
+
+Renames the keys of the [`Files`](#files) object, which represent the paths. For example, to remove the `*.go` suffix you can use:
+
+```js
+const rename = require('@now/build-utils')
+const originalFiles = { 'one.go': fileFsRef1, 'two.go': fileFsRef2 }
+const renamedFiles = rename(originalFiles, path => path.replace(/\.go$/, '')
+```

README.md

@@ -1,27 +1,65 @@
 # now-builders
 
-This is the full list of official Builders provided by the ZEIT team.
+This is a monorepo containing the [Official Builders](https://zeit.co/docs/v2/advanced/builders) provided by the ZEIT team.
 
-More details here: https://zeit.co/docs/v2/deployments/builders/overview/
+## Channels
+
+There are two Channels:
+
+| Channel | Git Branch                                                    | npm dist-tag | use example        |
+| ------- | ------------------------------------------------------------- | ------------ | ------------------ |
+| Canary  | [canary](https://github.com/zeit/now-builders/commits/canary) | `@canary`    | `@now/node@canary` |
+| Stable  | [master](https://github.com/zeit/now-builders/commits/master) | `@latest`    | `@now/node@latest` |
+
+All PRs should be submitted to the `canary` branch.
+
+Once a PR is merged into the `canary` branch, it should be published to npm immediately using the Canary Channel.
 
 ### Publishing to npm
 
-Run the following command to publish modified builders to npm:
+For the Canary Channel, publish the modified Builders to npm with the following:
-
-For the stable channel use:
-
-```
-yarn publish-stable
-```
-
-For the canary channel use:
 
 ```
 yarn publish-canary
 ```
 
-CircleCI will take care of publishing the updated packages to npm from there.
+For the Stable Channel, you must do the following:
 
-If for some reason CircleCI fails to publish the npm package, you may do so
+- Cherry pick each commit from canary to master
+- Verify that you are _in-sync_ with canary (with the exception of the `version` line in `package.json`)
+- Deploy the modified Builders
+
+```
+# View differences excluding "Publish" commits
+git checkout canary && git pull
+git log --pretty=format:"$ad- %s [%an]" | grep -v Publish > ~/Desktop/canary.txt
+git checkout master && git pull
+git log --pretty=format:"$ad- %s [%an]" | grep -v Publish > ~/Desktop/master.txt
+diff ~/Desktop/canary.txt ~/Desktop/master.txt
+
+# Cherry pick all PRs from canary into master ...
+git cherry-pick <PR501_COMMIT_SHA>
+git cherry-pick <PR502_COMMIT_SHA>
+git cherry-pick <PR503_COMMIT_SHA>
+git cherry-pick <PR504_COMMIT_SHA>
+
+# Verify the only difference is "version" in package.json
+git diff origin/canary
+
+# Ship it
+yarn publish-stable
+```
+
+After running this publish step, GitHub Actions will take care of publishing the modified Builder packages to npm.
+
+If for some reason GitHub Actions fails to publish the npm package, you may do so
 manually by running `npm publish` from the package directory. Make sure to
-include the `--tag canary` parameter if you are publishing a canary release!
+use `npm publish --tag canary` if you are publishing a canary release!
+
+### Contributing
+
+See the [Contribution guidelines for this project](CONTRIBUTING.md), it also contains guidance on interpreting tests failures.
+
+### Creating Your Own Builder
+
+To create your own Builder, see [the Builder's Developer Reference](DEVELOPING_A_BUILDER.md).

errors/now-next-legacy-mode.md

@@ -29,12 +29,11 @@ Serverless:
 - No runtime dependencies, meaning smaller lambda functions
 - Optimized for fast [cold start](https://zeit.co/blog/serverless-ssr#cold-start)
 
-
 #### Possible Ways to Fix It
 
 In order to create the smallest possible lambdas Next.js has to be configured to build for the `serverless` target.
 
-1. Serverless Next.js requires Next.js 8 or later, to upgrade you can install the `latest` version: 
+1. Serverless Next.js requires Next.js 8 or later, to upgrade you can install the `latest` version:
 
 ```
 npm install next --save
@@ -46,7 +45,7 @@ npm install next --save
 {
   "scripts": {
     "now-build": "next build"
-  },
+  }
 }
 ```
 
@@ -54,9 +53,9 @@ npm install next --save
 
 ```js
 module.exports = {
-  target: 'serverless'
+  target: 'serverless',
   // Other options are still valid
-}
+};
 ```
 
 4. Optionally make sure the `"src"` in `"builds"` points to your application `package.json`
@@ -70,4 +69,4 @@ module.exports = {
 
 ### Useful Links
 
-- [Serverless target implementation](https://github.com/zeit/now-builders/pull/150) 
+- [Serverless target implementation](https://github.com/zeit/now-builders/pull/150)

errors/now-next-no-serverless-pages-built.md

@@ -20,7 +20,7 @@ npm install next --save
 {
   "scripts": {
     "now-build": "next build"
-  },
+  }
 }
 ```
 
@@ -28,9 +28,9 @@ npm install next --save
 
 ```js
 module.exports = {
-  target: 'serverless'
+  target: 'serverless',
   // Other options
-}
+};
 ```
 
 4. Remove `distDir` from `next.config.js` as `@now/next` can't parse this file and expects your build output at `/.next`

errors/now-static-build-failed-to-detect-a-server.md

@@ -0,0 +1,38 @@
+# `@now/static-build` Failed to detect a server running
+
+#### Why This Warning Occurred
+
+When running `now dev`, the `@now/static-build` builder proxies relevant HTTP
+requests to the server that is created by the `now-dev` script in the
+`package.json` file.
+
+In order for `now dev` to know which port the server is running on, the builder
+is provided a `$PORT` environment variable that the server _must_ bind to. The
+error "Failed to detect a server running on port" is printed if the builder fails
+to detect a server listening on that specific port within five minutes.
+
+#### Possible Ways to Fix It
+
+Please ensure that your `now-dev` script binds the spawned development server on
+the provided `$PORT` that the builder expects the server to bind to.
+
+For example, if you are using Gatsby, your `now-dev` script must use the `-p`
+(port) option to bind to the `$PORT` specified from the builder:
+
+```
+{
+  ...
+  "scripts": {
+    ...
+    "now-dev": "gatsby develop -p $PORT"
+  }
+}
+```
+
+Consult your static builder program's `--help` or documentation to figure out what
+the command line flag to bind to a specific port is (in many cases, it is one of:
+`-p` / `-P` / `--port`).
+
+### Useful Links
+
+- [`@now/static-build` Local Development Documentation](https://zeit.co/docs/v2/deployments/official-builders/static-build-now-static-build#local-development)

jest.config.js

@@ -1,5 +1,35 @@
+const { execSync } = require('child_process');
+const { relative } = require('path');
+
+const branch = execSync('git branch | grep "*" | cut -d " " -f2')
+  .toString()
+  .trim();
+console.log(`Running tests on branch "${branch}"`);
+const gitPath = branch === 'master' ? 'HEAD~1' : 'origin/canary...HEAD';
+const diff = execSync(`git diff ${gitPath} --name-only`).toString();
+
+const changed = diff
+  .split('\n')
+  .filter(item => Boolean(item) && item.includes('packages/'))
+  .map(item => relative('packages', item).split('/')[0]);
+
+const matches = Array.from(new Set(changed));
+
+if (matches.length === 0) {
+  matches.push('now-node');
+  console.log(`No packages changed, defaulting to ${matches[0]}`);
+} else {
+  console.log('The following packages have changed:');
+  console.log(matches.join('\n'));
+}
+
+const testMatch = matches.map(
+  item => `**/${item}/**/?(*.)+(spec|test).[jt]s?(x)`,
+);
+
 module.exports = {
   testEnvironment: 'node',
+  testMatch,
   collectCoverageFrom: [
     'packages/(!test)/**/*.{js,jsx}',
     '!**/node_modules/**',

lerna.json

@@ -1,9 +1,7 @@
 {
   "npmClient": "yarn",
   "useWorkspaces": true,
-  "packages": [
+  "packages": ["packages/*"],
-    "packages/*"
-  ],
   "command": {
     "publish": {
       "npmClient": "npm",

package.json

@@ -12,8 +12,9 @@
   "scripts": {
     "lerna": "lerna",
     "bootstrap": "lerna bootstrap",
-    "publish-stable": "lerna version",
+    "publish-stable": "git checkout master && git pull && lerna version --exact",
-    "publish-canary": "lerna version prerelease --preid canary",
+    "publish-canary": "git checkout canary && git pull && lerna version prerelease --preid canary --exact",
+    "publish-from-github": "./.circleci/publish.sh",
     "build": "./.circleci/build.sh",
     "lint": "eslint .",
     "codecov": "codecov",
@@ -31,26 +32,35 @@
     "*.ts": [
       "prettier --write",
       "git add"
+    ],
+    "*.json": [
+      "prettier --write",
+      "git add"
+    ],
+    "*.md": [
+      "prettier --write",
+      "git add"
     ]
   },
   "devDependencies": {
-    "@types/fs-extra": "^5.0.4",
+    "@types/node": "*",
-    "@types/glob": "^7.1.1",
+    "@zeit/ncc": "0.20.4",
-    "@types/multistream": "^2.1.1",
-    "@types/node": "^10.12.8",
     "async-retry": "1.2.3",
-    "buffer-replace": "^1.0.0",
+    "buffer-replace": "1.0.0",
-    "codecov": "^3.2.0",
+    "codecov": "3.2.0",
-    "eslint": "^5.9.0",
+    "eslint": "5.9.0",
-    "eslint-config-airbnb-base": "^13.1.0",
+    "eslint-config-airbnb-base": "13.1.0",
-    "eslint-config-prettier": "^3.1.0",
+    "eslint-config-prettier": "3.3.0",
-    "eslint-plugin-import": "^2.14.0",
+    "eslint-plugin-import": "2.14.0",
     "fs-extra": "^7.0.1",
-    "glob": "^7.1.3",
+    "jest": "24.7.1",
-    "jest": "^23.6.0",
+    "lint-staged": "8.1.0",
-    "lint-staged": "^8.0.4",
+    "node-fetch": "2.6.0",
-    "node-fetch": "^2.3.0",
+    "pre-commit": "1.2.2",
-    "pre-commit": "^1.2.2",
+    "prettier": "1.17.1"
-    "prettier": "^1.15.2"
+  },
+  "prettier": {
+    "singleQuote": true,
+    "trailingComma": "es5"
   }
 }

packages/now-bash/bootstrap

@@ -1,16 +0,0 @@
-#!/bin/bash
-set -euo pipefail
-cd "$LAMBDA_TASK_ROOT"
-
-# Configure `import`
-export IMPORT_CACHE="$LAMBDA_TASK_ROOT/.import-cache"
-export PATH="$IMPORT_CACHE/bin:$PATH"
-
-# Load `import` and runtime
-# shellcheck disable=SC1090
-. "$(which import)"
-# shellcheck disable=SC1090
-. "$IMPORT_CACHE/runtime.sh"
-
-# Load user code and process events in a loop forever
-_lambda_runtime_init

packages/now-bash/builder.sh

@@ -1,40 +0,0 @@
-#!/bin/bash
-set -euo pipefail
-
-# `import` debug logs are always enabled during build
-export IMPORT_DEBUG=1
-
-# Install `import`
-IMPORT_BIN="$IMPORT_CACHE/bin/import"
-mkdir -p "$(dirname "$IMPORT_BIN")"
-curl -sfLS https://import.pw > "$IMPORT_BIN"
-chmod +x "$IMPORT_BIN"
-
-# For now only the entrypoint file is copied into the lambda
-mkdir -p "$(dirname "$ENTRYPOINT")"
-cp "$SRC/$ENTRYPOINT" "$ENTRYPOINT"
-
-# Copy in the runtime
-cp "$BUILDER/runtime.sh" "$IMPORT_CACHE"
-cp "$BUILDER/bootstrap" .
-
-# Load `import`
-. "$(which import)"
-
-# Cache runtime and user dependencies
-echo "Caching imports in \"$ENTRYPOINT\"…"
-. "$IMPORT_CACHE/runtime.sh"
-. "$ENTRYPOINT"
-echo "Done caching imports"
-
-# Run user build script
-if declare -f build > /dev/null; then
-	echo "Running \`build\` function in \"$ENTRYPOINT\"…"
-	build "$@"
-fi
-
-# Ensure the entrypoint defined a `handler` function
-if ! declare -f handler > /dev/null; then
-	echo "ERROR: A \`handler\` function must be defined in \"$ENTRYPOINT\"!" >&2
-	exit 1
-fi

packages/now-bash/index.js

@@ -1,57 +0,0 @@
-const execa = require('execa');
-const { join } = require('path');
-const snakeCase = require('snake-case');
-const glob = require('@now/build-utils/fs/glob'); // eslint-disable-line import/no-extraneous-dependencies
-const download = require('@now/build-utils/fs/download'); // eslint-disable-line import/no-extraneous-dependencies
-const { createLambda } = require('@now/build-utils/lambda'); // eslint-disable-line import/no-extraneous-dependencies
-const getWritableDirectory = require('@now/build-utils/fs/get-writable-directory'); // eslint-disable-line import/no-extraneous-dependencies
-
-exports.config = {
-  maxLambdaSize: '10mb',
-};
-
-exports.analyze = ({ files, entrypoint }) => files[entrypoint].digest;
-
-exports.build = async ({
-  workPath, files, entrypoint, config,
-}) => {
-  const srcDir = await getWritableDirectory();
-
-  console.log('downloading files...');
-  await download(files, srcDir);
-
-  const configEnv = Object.keys(config).reduce((o, v) => {
-    o[`IMPORT_${snakeCase(v).toUpperCase()}`] = config[v]; // eslint-disable-line no-param-reassign
-    return o;
-  }, {});
-
-  const IMPORT_CACHE = `${workPath}/.import-cache`;
-  const env = Object.assign({}, process.env, configEnv, {
-    PATH: `${IMPORT_CACHE}/bin:${process.env.PATH}`,
-    IMPORT_CACHE,
-    SRC: srcDir,
-    BUILDER: __dirname,
-    ENTRYPOINT: entrypoint,
-  });
-
-  const builderPath = join(__dirname, 'builder.sh');
-
-  await execa(builderPath, [entrypoint], {
-    env,
-    cwd: workPath,
-    stdio: 'inherit',
-  });
-
-  const lambda = await createLambda({
-    files: await glob('**', workPath),
-    handler: entrypoint, // not actually used in `bootstrap`
-    runtime: 'provided',
-    environment: Object.assign({}, configEnv, {
-      SCRIPT_FILENAME: entrypoint,
-    }),
-  });
-
-  return {
-    [entrypoint]: lambda,
-  };
-};

packages/now-bash/package.json

@@ -1,24 +0,0 @@
-{
-  "name": "@now/bash",
-  "version": "0.2.0",
-  "description": "Now 2.0 builder for HTTP endpoints written in Bash",
-  "main": "index.js",
-  "author": "Nathan Rajlich <nate@zeit.co>",
-  "license": "MIT",
-  "repository": {
-    "type": "git",
-    "url": "https://github.com/zeit/now-builders.git",
-    "directory": "packages/now-bash"
-  },
-  "files": [
-    "builder.sh",
-    "runtime.sh",
-    "bootstrap",
-    "index.js",
-    "package.json"
-  ],
-  "dependencies": {
-    "execa": "^1.0.0",
-    "snake-case": "^2.1.0"
-  }
-}

packages/now-bash/runtime.sh

@@ -1,119 +0,0 @@
-#!/bin/bash
-import "static-binaries@1.0.0"
-static_binaries jq
-
-# These get reset upon each request
-_STATUS_CODE="$(mktemp)"
-_HEADERS="$(mktemp)"
-
-_lambda_runtime_api() {
-	local endpoint="$1"
-	shift
-	curl -sfLS "http://$AWS_LAMBDA_RUNTIME_API/2018-06-01/runtime/$endpoint" "$@"
-}
-
-_lambda_runtime_init() {
-	# Initialize user code
-	# shellcheck disable=SC1090
-	. "$SCRIPT_FILENAME" || {
-		local exit_code="$?"
-		local error_message="Initialization failed for '$SCRIPT_FILENAME' (exit code $exit_code)"
-		echo "$error_message" >&2
-		local error='{"errorMessage":"'"$error_message"'"}'
-		_lambda_runtime_api "init/error" -X POST -d "$error"
-		exit "$exit_code"
-	}
-
-	# Process events
-	while true; do _lambda_runtime_next; done
-}
-
-_lambda_runtime_next() {
-	echo 200 > "$_STATUS_CODE"
-	echo '{"content-type":"text/plain; charset=utf8"}' > "$_HEADERS"
-
-	local headers
-	headers="$(mktemp)"
-
-	# Get an event
-	local event
-	event="$(mktemp)"
-	_lambda_runtime_api invocation/next -D "$headers" | jq --raw-output --monochrome-output '.body' > "$event"
-
-	local request_id
-	request_id="$(grep -Fi Lambda-Runtime-Aws-Request-Id "$headers" | tr -d '[:space:]' | cut -d: -f2)"
-	rm -f "$headers"
-
-	# Execute the handler function from the script
-	local body
-	body="$(mktemp)"
-
-	# Stdin of the `handler` function is the HTTP request body.
-	# Need to use a fifo here instead of bash <() because Lambda
-	# errors with "/dev/fd/63 not found" for some reason :/
-	local stdin
-	stdin="$(mktemp -u)"
-	mkfifo "$stdin"
-	_lambda_runtime_body < "$event" > "$stdin" &
-
-	local exit_code=0
-	handler "$event" < "$stdin" > "$body" || exit_code="$?"
-
-	rm -f "$event" "$stdin"
-
-	if [ "$exit_code" -eq 0 ]; then
-		# Send the response
-		jq --raw-input --raw-output --compact-output --slurp --monochrome-output \
-			--arg statusCode "$(cat "$_STATUS_CODE")" \
-			--argjson headers "$(cat "$_HEADERS")" \
-			'{statusCode:$statusCode|tonumber, headers:$headers, encoding:"base64", body:.|@base64}' < "$body" \
-			| _lambda_runtime_api "invocation/$request_id/response" -X POST -d @- > /dev/null
-		rm -f "$body" "$_HEADERS"
-	else
-		local error_message="Invocation failed for 'handler' function in '$SCRIPT_FILENAME' (exit code $exit_code)"
-		echo "$error_message" >&2
-		_lambda_runtime_api "invocation/$request_id/error" -X POST -d '{"errorMessage":"'"$error_message"'"}' > /dev/null
-	fi
-}
-
-_lambda_runtime_body() {
-	local event
-	event="$(cat)"
-	if [ "$(jq --raw-output '.body | type' <<< "$event")" = "string" ]; then
-		if [ "$(jq --raw-output '.encoding' <<< "$event")" = "base64" ]; then
-			jq --raw-output '.body' <<< "$event" | base64 --decode
-		else
-			# assume plain-text body
-			jq --raw-output '.body' <<< "$event"
-		fi
-	fi
-}
-
-
-# Set the response status code.
-http_response_code() {
-	echo "$1" > "$_STATUS_CODE"
-}
-
-# Sets a response header.
-# Overrides existing header if it has already been set.
-http_response_header() {
-	local name="$1"
-	local value="$2"
-	local tmp
-	tmp="$(mktemp)"
-	jq \
-		--arg name "$name" \
-		--arg value "$value" \
-		'.[$name] = $value' < "$_HEADERS" > "$tmp"
-	mv -f "$tmp" "$_HEADERS"
-}
-
-http_response_redirect() {
-	http_response_code "${2:-302}"
-	http_response_header "location" "$1"
-}
-
-http_response_json() {
-	http_response_header "content-type" "application/json; charset=utf8"
-}

packages/now-bash/yarn.lock

@@ -1,146 +0,0 @@
-# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
-# yarn lockfile v1
-
-
-cross-spawn@^6.0.0:
-  version "6.0.5"
-  resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-6.0.5.tgz#4a5ec7c64dfae22c3a14124dbacdee846d80cbc4"
-  integrity sha512-eTVLrBSt7fjbDygz805pMnstIs2VTBNkRm0qxZd+M7A5XDdxVRWO5MxGBXZhjY4cqLYLdtrGqRf8mBPmzwSpWQ==
-  dependencies:
-    nice-try "^1.0.4"
-    path-key "^2.0.1"
-    semver "^5.5.0"
-    shebang-command "^1.2.0"
-    which "^1.2.9"
-
-end-of-stream@^1.1.0:
-  version "1.4.1"
-  resolved "https://registry.yarnpkg.com/end-of-stream/-/end-of-stream-1.4.1.tgz#ed29634d19baba463b6ce6b80a37213eab71ec43"
-  integrity sha512-1MkrZNvWTKCaigbn+W15elq2BB/L22nqrSY5DKlo3X6+vclJm8Bb5djXJBmEX6fS3+zCh/F4VBK5Z2KxJt4s2Q==
-  dependencies:
-    once "^1.4.0"
-
-execa@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/execa/-/execa-1.0.0.tgz#c6236a5bb4df6d6f15e88e7f017798216749ddd8"
-  integrity sha512-adbxcyWV46qiHyvSp50TKt05tB4tK3HcmF7/nxfAdhnox83seTDbwnaqKO4sXRy7roHAIFqJP/Rw/AuEbX61LA==
-  dependencies:
-    cross-spawn "^6.0.0"
-    get-stream "^4.0.0"
-    is-stream "^1.1.0"
-    npm-run-path "^2.0.0"
-    p-finally "^1.0.0"
-    signal-exit "^3.0.0"
-    strip-eof "^1.0.0"
-
-get-stream@^4.0.0:
-  version "4.1.0"
-  resolved "https://registry.yarnpkg.com/get-stream/-/get-stream-4.1.0.tgz#c1b255575f3dc21d59bfc79cd3d2b46b1c3a54b5"
-  integrity sha512-GMat4EJ5161kIy2HevLlr4luNjBgvmj413KaQA7jt4V8B4RDsfpHk7WQ9GVqfYyyx8OS/L66Kox+rJRNklLK7w==
-  dependencies:
-    pump "^3.0.0"
-
-is-stream@^1.1.0:
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/is-stream/-/is-stream-1.1.0.tgz#12d4a3dd4e68e0b79ceb8dbc84173ae80d91ca44"
-  integrity sha1-EtSj3U5o4Lec6428hBc66A2RykQ=
-
-isexe@^2.0.0:
-  version "2.0.0"
-  resolved "https://registry.yarnpkg.com/isexe/-/isexe-2.0.0.tgz#e8fbf374dc556ff8947a10dcb0572d633f2cfa10"
-  integrity sha1-6PvzdNxVb/iUehDcsFctYz8s+hA=
-
-lower-case@^1.1.1:
-  version "1.1.4"
-  resolved "https://registry.yarnpkg.com/lower-case/-/lower-case-1.1.4.tgz#9a2cabd1b9e8e0ae993a4bf7d5875c39c42e8eac"
-  integrity sha1-miyr0bno4K6ZOkv31YdcOcQujqw=
-
-nice-try@^1.0.4:
-  version "1.0.5"
-  resolved "https://registry.yarnpkg.com/nice-try/-/nice-try-1.0.5.tgz#a3378a7696ce7d223e88fc9b764bd7ef1089e366"
-  integrity sha512-1nh45deeb5olNY7eX82BkPO7SSxR5SSYJiPTrTdFUVYwAl8CKMA5N9PjTYkHiRjisVcxcQ1HXdLhx2qxxJzLNQ==
-
-no-case@^2.2.0:
-  version "2.3.2"
-  resolved "https://registry.yarnpkg.com/no-case/-/no-case-2.3.2.tgz#60b813396be39b3f1288a4c1ed5d1e7d28b464ac"
-  integrity sha512-rmTZ9kz+f3rCvK2TD1Ue/oZlns7OGoIWP4fc3llxxRXlOkHKoWPPWJOfFYpITabSow43QJbRIoHQXtt10VldyQ==
-  dependencies:
-    lower-case "^1.1.1"
-
-npm-run-path@^2.0.0:
-  version "2.0.2"
-  resolved "https://registry.yarnpkg.com/npm-run-path/-/npm-run-path-2.0.2.tgz#35a9232dfa35d7067b4cb2ddf2357b1871536c5f"
-  integrity sha1-NakjLfo11wZ7TLLd8jV7GHFTbF8=
-  dependencies:
-    path-key "^2.0.0"
-
-once@^1.3.1, once@^1.4.0:
-  version "1.4.0"
-  resolved "https://registry.yarnpkg.com/once/-/once-1.4.0.tgz#583b1aa775961d4b113ac17d9c50baef9dd76bd1"
-  integrity sha1-WDsap3WWHUsROsF9nFC6753Xa9E=
-  dependencies:
-    wrappy "1"
-
-p-finally@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/p-finally/-/p-finally-1.0.0.tgz#3fbcfb15b899a44123b34b6dcc18b724336a2cae"
-  integrity sha1-P7z7FbiZpEEjs0ttzBi3JDNqLK4=
-
-path-key@^2.0.0, path-key@^2.0.1:
-  version "2.0.1"
-  resolved "https://registry.yarnpkg.com/path-key/-/path-key-2.0.1.tgz#411cadb574c5a140d3a4b1910d40d80cc9f40b40"
-  integrity sha1-QRyttXTFoUDTpLGRDUDYDMn0C0A=
-
-pump@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/pump/-/pump-3.0.0.tgz#b4a2116815bde2f4e1ea602354e8c75565107a64"
-  integrity sha512-LwZy+p3SFs1Pytd/jYct4wpv49HiYCqd9Rlc5ZVdk0V+8Yzv6jR5Blk3TRmPL1ft69TxP0IMZGJ+WPFU2BFhww==
-  dependencies:
-    end-of-stream "^1.1.0"
-    once "^1.3.1"
-
-semver@^5.5.0:
-  version "5.6.0"
-  resolved "https://registry.yarnpkg.com/semver/-/semver-5.6.0.tgz#7e74256fbaa49c75aa7c7a205cc22799cac80004"
-  integrity sha512-RS9R6R35NYgQn++fkDWaOmqGoj4Ek9gGs+DPxNUZKuwE183xjJroKvyo1IzVFeXvUrvmALy6FWD5xrdJT25gMg==
-
-shebang-command@^1.2.0:
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/shebang-command/-/shebang-command-1.2.0.tgz#44aac65b695b03398968c39f363fee5deafdf1ea"
-  integrity sha1-RKrGW2lbAzmJaMOfNj/uXer98eo=
-  dependencies:
-    shebang-regex "^1.0.0"
-
-shebang-regex@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/shebang-regex/-/shebang-regex-1.0.0.tgz#da42f49740c0b42db2ca9728571cb190c98efea3"
-  integrity sha1-2kL0l0DAtC2yypcoVxyxkMmO/qM=
-
-signal-exit@^3.0.0:
-  version "3.0.2"
-  resolved "https://registry.yarnpkg.com/signal-exit/-/signal-exit-3.0.2.tgz#b5fdc08f1287ea1178628e415e25132b73646c6d"
-  integrity sha1-tf3AjxKH6hF4Yo5BXiUTK3NkbG0=
-
-snake-case@^2.1.0:
-  version "2.1.0"
-  resolved "https://registry.yarnpkg.com/snake-case/-/snake-case-2.1.0.tgz#41bdb1b73f30ec66a04d4e2cad1b76387d4d6d9f"
-  integrity sha1-Qb2xtz8w7GagTU4srRt2OH1NbZ8=
-  dependencies:
-    no-case "^2.2.0"
-
-strip-eof@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/strip-eof/-/strip-eof-1.0.0.tgz#bb43ff5598a6eb05d89b59fcd129c983313606bf"
-  integrity sha1-u0P/VZim6wXYm1n80SnJgzE2Br8=
-
-which@^1.2.9:
-  version "1.3.1"
-  resolved "https://registry.yarnpkg.com/which/-/which-1.3.1.tgz#a45043d54f5805316da8d62f9f50918d3da70b0a"
-  integrity sha512-HxJdYWq1MTIQbJ3nw0cqssHoTNU267KlrDuGZ1WYlxDStUtKUhOaJmh112/TZmHxxUfuJqPXSOm7tDyas0OSIQ==
-  dependencies:
-    isexe "^2.0.0"
-
-wrappy@1:
-  version "1.0.2"
-  resolved "https://registry.yarnpkg.com/wrappy/-/wrappy-1.0.2.tgz#b5243d8f3ec1aa35f1364605bc0d1036e30ab69f"
-  integrity sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8=

packages/now-build-utils/build.sh

@@ -0,0 +1,6 @@
+tsc
+
+rm dist/index.js
+ncc build src/index.ts -o dist/main
+mv dist/main/index.js dist/index.js
+rm -rf dist/main

packages/now-build-utils/fs/download.js

@@ -1 +1 @@
-module.exports = require('../dist/fs/download').default;
+module.exports = require('../dist/index').download;

packages/now-build-utils/fs/get-writable-directory.js

@@ -1 +1 @@
-module.exports = require('../dist/fs/get-writable-directory').default;
+module.exports = require('../dist/index').getWriteableDirectory;

packages/now-build-utils/fs/glob.js

@@ -1 +1 @@
-module.exports = require('../dist/fs/glob').default;
+module.exports = require('../dist/index').glob;

packages/now-build-utils/fs/rename.js

@@ -1 +1 @@
-module.exports = require('../dist/fs/rename').default;
+module.exports = require('../dist/index').rename;

packages/now-build-utils/fs/run-user-scripts.js

@@ -1 +1 @@
-module.exports = require('../dist/fs/run-user-scripts');
+module.exports = require('../dist/index');

packages/now-build-utils/fs/stream-to-buffer.js

@@ -1 +1 @@
-module.exports = require('../dist/fs/stream-to-buffer').default;
+module.exports = require('../dist/index').streamToBuffer;

packages/now-build-utils/package.json

@@ -1,39 +1,43 @@
 {
   "name": "@now/build-utils",
-  "version": "0.5.0",
+  "version": "0.9.11",
   "license": "MIT",
   "main": "./dist/index.js",
   "types": "./dist/index.d.js",
+  "homepage": "https://zeit.co/docs/v2/deployments/builders/developer-guide",
   "repository": {
     "type": "git",
     "url": "https://github.com/zeit/now-builders.git",
     "directory": "packages/now-build-utils"
   },
-  "dependencies": {
-    "async-retry": "1.2.3",
-    "async-sema": "2.1.4",
-    "end-of-stream": "1.4.1",
-    "fs-extra": "7.0.0",
-    "glob": "7.1.3",
-    "into-stream": "5.0.0",
-    "memory-fs": "0.4.1",
-    "multistream": "2.1.1",
-    "node-fetch": "2.2.0",
-    "yazl": "2.4.3"
-  },
   "scripts": {
-    "build": "tsc",
+    "build": "./build.sh",
-    "test": "tsc && jest",
+    "test": "./build.sh && jest",
-    "prepublish": "tsc"
+    "prepublishOnly": "./build.sh"
   },
   "devDependencies": {
     "@types/async-retry": "^1.2.1",
+    "@types/cross-spawn": "6.0.0",
     "@types/end-of-stream": "^1.4.0",
     "@types/fs-extra": "^5.0.5",
     "@types/glob": "^7.1.1",
+    "@types/multistream": "2.1.1",
     "@types/node-fetch": "^2.1.6",
+    "@types/semver": "6.0.0",
     "@types/yazl": "^2.4.1",
+    "async-retry": "1.2.3",
+    "async-sema": "2.1.4",
+    "cross-spawn": "6.0.5",
+    "end-of-stream": "1.4.1",
     "execa": "^1.0.0",
-    "typescript": "3.3.4000"
+    "fs-extra": "7.0.0",
+    "glob": "7.1.3",
+    "into-stream": "5.0.0",
+    "minimatch": "3.0.4",
+    "multistream": "2.1.1",
+    "node-fetch": "2.2.0",
+    "semver": "6.1.1",
+    "typescript": "3.5.2",
+    "yazl": "2.4.3"
   }
 }

packages/now-build-utils/src/debug.ts

@@ -0,0 +1,7 @@
+export default function debug(message: string, ...additional: any[]) {
+  if (process.env.NOW_BUILDER_DEBUG) {
+    console.log(message, ...additional);
+  } else if (process.env.NOW_BUILDER_ANNOTATE) {
+    console.log(`[now-builder-debug] ${message}`, ...additional);
+  }
+}

packages/now-build-utils/src/detect-builders.ts

@@ -0,0 +1,173 @@
+import { PackageJson, Builder, Config } from './types';
+import minimatch from 'minimatch';
+
+interface ErrorResponse {
+  code: string;
+  message: string;
+}
+
+interface Options {
+  tag?: 'canary' | 'latest';
+}
+
+const src: string = 'package.json';
+const config: Config = { zeroConfig: true };
+
+// Static builders are special cased in `@now/static-build`
+const BUILDERS = new Map<string, Builder>([
+  ['next', { src, use: '@now/next', config }],
+]);
+
+const API_BUILDERS: Builder[] = [
+  { src: 'api/**/*.js', use: '@now/node', config },
+  { src: 'api/**/*.ts', use: '@now/node', config },
+  { src: 'api/**/*.go', use: '@now/go', config },
+  { src: 'api/**/*.py', use: '@now/python', config },
+  { src: 'api/**/*.rb', use: '@now/ruby', config },
+];
+
+const MISSING_BUILD_SCRIPT_ERROR: ErrorResponse = {
+  code: 'missing_build_script',
+  message:
+    'Your `package.json` file is missing a `build` property inside the `script` property.' +
+    '\nMore details: https://zeit.co/docs/v2/advanced/platform/frequently-asked-questions#missing-build-script',
+};
+
+function hasPublicDirectory(files: string[]) {
+  return files.some(name => name.startsWith('public/'));
+}
+
+function hasBuildScript(pkg: PackageJson | undefined) {
+  const { scripts = {} } = pkg || {};
+  return Boolean(scripts && scripts['build']);
+}
+
+async function detectBuilder(pkg: PackageJson): Promise<Builder> {
+  for (const [dependency, builder] of BUILDERS) {
+    const deps = Object.assign({}, pkg.dependencies, pkg.devDependencies);
+
+    // Return the builder when a dependency matches
+    if (deps[dependency]) {
+      return builder;
+    }
+  }
+
+  // By default we'll choose the `static-build` builder
+  return { src, use: '@now/static-build', config };
+}
+
+// Files that match a specific pattern will get ignored
+export function ignoreApiFilter(file: string) {
+  if (file.includes('/.')) {
+    return false;
+  }
+
+  if (file.includes('/_')) {
+    return false;
+  }
+
+  if (file.endsWith('.d.ts')) {
+    return false;
+  }
+
+  // If the file does not match any builder we also
+  // don't want to create a route e.g. `package.json`
+  if (API_BUILDERS.every(({ src }) => !minimatch(file, src))) {
+    return false;
+  }
+
+  return true;
+}
+
+// We need to sort the file paths by alphabet to make
+// sure the routes stay in the same order e.g. for deduping
+export function sortFiles(fileA: string, fileB: string) {
+  return fileA.localeCompare(fileB);
+}
+
+async function detectApiBuilders(files: string[]): Promise<Builder[]> {
+  const builds = files
+    .sort(sortFiles)
+    .filter(ignoreApiFilter)
+    .map(file => {
+      const result = API_BUILDERS.find(
+        ({ src }): boolean => minimatch(file, src)
+      );
+
+      return result ? { ...result, src: file } : null;
+    });
+
+  const finishedBuilds = builds.filter(Boolean);
+  return finishedBuilds as Builder[];
+}
+
+// When zero config is used we can call this function
+// to determine what builders to use
+export async function detectBuilders(
+  files: string[],
+  pkg?: PackageJson | undefined | null,
+  options?: Options
+): Promise<{
+  builders: Builder[] | null;
+  errors: ErrorResponse[] | null;
+}> {
+  const errors: ErrorResponse[] = [];
+
+  // Detect all builders for the `api` directory before anything else
+  let builders = await detectApiBuilders(files);
+
+  if (pkg && hasBuildScript(pkg)) {
+    builders.push(await detectBuilder(pkg));
+  } else {
+    if (pkg && builders.length === 0) {
+      // We only show this error when there are no api builders
+      // since the dependencies of the pkg could be used for those
+      errors.push(MISSING_BUILD_SCRIPT_ERROR);
+      return { errors, builders: null };
+    }
+
+    // We allow a `public` directory
+    // when there are no build steps
+    if (hasPublicDirectory(files)) {
+      builders.push({
+        use: '@now/static',
+        src: 'public/**/*',
+        config,
+      });
+    } else if (builders.length > 0) {
+      // We can't use pattern matching, since `!(api)` and `!(api)/**/*`
+      // won't give the correct results
+      builders.push(
+        ...files
+          .filter(name => !name.startsWith('api/'))
+          .filter(name => !(name === 'package.json'))
+          .map(name => ({
+            use: '@now/static',
+            src: name,
+            config,
+          }))
+      );
+    }
+  }
+
+  // Change the tag for the builders
+  if (builders && builders.length) {
+    const tag = options && options.tag;
+
+    if (tag) {
+      builders = builders.map((builder: Builder) => {
+        // @now/static has no canary builder
+        if (builder.use !== '@now/static') {
+          builder.use = `${builder.use}@${tag}`;
+        }
+
+        return builder;
+      });
+    }
+  }
+
+  return {
+    builders: builders.length ? builders : null,
+    errors: errors.length ? errors : null,
+  };
+}

packages/now-build-utils/src/detect-routes.ts

@@ -0,0 +1,286 @@
+import { Route, Builder } from './types';
+import { parse as parsePath } from 'path';
+import { ignoreApiFilter, sortFiles } from './detect-builders';
+
+function escapeName(name: string) {
+  const special = '[]^$.|?*+()'.split('');
+
+  for (const char of special) {
+    name = name.replace(new RegExp(`\\${char}`, 'g'), `\\${char}`);
+  }
+
+  return name;
+}
+
+function joinPath(...segments: string[]) {
+  const joinedPath = segments.join('/');
+  return joinedPath.replace(/\/{2,}/g, '/');
+}
+
+function concatArrayOfText(texts: string[]): string {
+  if (texts.length <= 2) {
+    return texts.join(' and ');
+  }
+
+  const last = texts.pop();
+  return `${texts.join(', ')}, and ${last}`;
+}
+
+// Takes a filename or foldername, strips the extension
+// gets the part between the "[]" brackets.
+// It will return `null` if there are no brackets
+// and therefore no segment.
+function getSegmentName(segment: string): string | null {
+  const { name } = parsePath(segment);
+
+  if (name.startsWith('[') && name.endsWith(']')) {
+    return name.slice(1, -1);
+  }
+
+  return null;
+}
+
+function createRouteFromPath(filePath: string): Route {
+  const parts = filePath.split('/');
+
+  let counter: number = 1;
+  const query: string[] = [];
+
+  const srcParts = parts.map(
+    (segment, index): string => {
+      const name = getSegmentName(segment);
+      const isLast = index === parts.length - 1;
+
+      if (name !== null) {
+        // We can't use `URLSearchParams` because `$` would get escaped
+        query.push(`${name}=$${counter++}`);
+        return `([^\\/]+)`;
+      } else if (isLast) {
+        const { name: fileName, ext } = parsePath(segment);
+        const isIndex = fileName === 'index';
+
+        // Either filename with extension, filename without extension
+        // or nothing when the filename is `index`
+        return `(${escapeName(fileName)}|${escapeName(fileName)}${escapeName(
+          ext
+        )})${isIndex ? '?' : ''}`;
+      }
+
+      return segment;
+    }
+  );
+
+  const src = `^/${srcParts.join('/')}$`;
+  const dest = `/${filePath}${query.length ? '?' : ''}${query.join('&')}`;
+
+  return { src, dest };
+}
+
+// Check if the path partially matches and has the same
+// name for the path segment at the same position
+function partiallyMatches(pathA: string, pathB: string): boolean {
+  const partsA = pathA.split('/');
+  const partsB = pathB.split('/');
+
+  const long = partsA.length > partsB.length ? partsA : partsB;
+  const short = long === partsA ? partsB : partsA;
+
+  let index = 0;
+
+  for (const segmentShort of short) {
+    const segmentLong = long[index];
+
+    const nameLong = getSegmentName(segmentLong);
+    const nameShort = getSegmentName(segmentShort);
+
+    // If there are no segments or the paths differ we
+    // return as they are not matching
+    if (segmentShort !== segmentLong && (!nameLong || !nameShort)) {
+      return false;
+    }
+
+    if (nameLong !== nameShort) {
+      return true;
+    }
+
+    index += 1;
+  }
+
+  return false;
+}
+
+// Counts how often a path occurres when all placeholders
+// got resolved, so we can check if they have conflicts
+function pathOccurrences(filePath: string, files: string[]): string[] {
+  const getAbsolutePath = (unresolvedPath: string): string => {
+    const { dir, name } = parsePath(unresolvedPath);
+    const parts = joinPath(dir, name).split('/');
+    return parts.map(part => part.replace(/\[.*\]/, '1')).join('/');
+  };
+
+  const currentAbsolutePath = getAbsolutePath(filePath);
+
+  return files.reduce((prev: string[], file: string): string[] => {
+    const absolutePath = getAbsolutePath(file);
+
+    if (absolutePath === currentAbsolutePath) {
+      prev.push(file);
+    } else if (partiallyMatches(filePath, file)) {
+      prev.push(file);
+    }
+
+    return prev;
+  }, []);
+}
+
+// Checks if a placeholder with the same name is used
+// multiple times inside the same path
+function getConflictingSegment(filePath: string): string | null {
+  const segments = new Set<string>();
+
+  for (const segment of filePath.split('/')) {
+    const name = getSegmentName(segment);
+
+    if (name !== null && segments.has(name)) {
+      return name;
+    }
+
+    if (name) {
+      segments.add(name);
+    }
+  }
+
+  return null;
+}
+
+function sortFilesBySegmentCount(fileA: string, fileB: string): number {
+  const lengthA = fileA.split('/').length;
+  const lengthB = fileB.split('/').length;
+
+  if (lengthA > lengthB) {
+    return -1;
+  }
+
+  if (lengthA < lengthB) {
+    return 1;
+  }
+
+  // Paths that have the same segment length but
+  // less placeholders are preferred
+  const countSegments = (prev: number, segment: string) =>
+    getSegmentName(segment) ? prev + 1 : 0;
+  const segmentLengthA = fileA.split('/').reduce(countSegments, 0);
+  const segmentLengthB = fileB.split('/').reduce(countSegments, 0);
+
+  if (segmentLengthA > segmentLengthB) {
+    return 1;
+  }
+
+  if (segmentLengthA < segmentLengthB) {
+    return -1;
+  }
+
+  return 0;
+}
+
+interface RoutesResult {
+  defaultRoutes: Route[] | null;
+  error: { [key: string]: string } | null;
+}
+
+async function detectApiRoutes(files: string[]): Promise<RoutesResult> {
+  if (!files || files.length === 0) {
+    return { defaultRoutes: null, error: null };
+  }
+
+  // The deepest routes need to be
+  // the first ones to get handled
+  const sortedFiles = files
+    .filter(ignoreApiFilter)
+    .sort(sortFiles)
+    .sort(sortFilesBySegmentCount);
+
+  const defaultRoutes: Route[] = [];
+
+  for (const file of sortedFiles) {
+    // We only consider every file in the api directory
+    // as we will strip extensions as well as resolving "[segments]"
+    if (!file.startsWith('api/')) {
+      continue;
+    }
+
+    const conflictingSegment = getConflictingSegment(file);
+
+    if (conflictingSegment) {
+      return {
+        defaultRoutes: null,
+        error: {
+          code: 'conflicting_path_segment',
+          message:
+            `The segment "${conflictingSegment}" occurres more than ` +
+            `one time in your path "${file}". Please make sure that ` +
+            `every segment in a path is unique`,
+        },
+      };
+    }
+
+    const occurrences = pathOccurrences(file, sortedFiles).filter(
+      name => name !== file
+    );
+
+    if (occurrences.length > 0) {
+      const messagePaths = concatArrayOfText(
+        occurrences.map(name => `"${name}"`)
+      );
+
+      return {
+        defaultRoutes: null,
+        error: {
+          code: 'conflicting_file_path',
+          message:
+            `Two or more files have conflicting paths or names. ` +
+            `Please make sure path segments and filenames, without their extension, are unique. ` +
+            `The path "${file}" has conflicts with ${messagePaths}`,
+        },
+      };
+    }
+
+    defaultRoutes.push(createRouteFromPath(file));
+  }
+
+  // 404 Route to disable directory listing
+  if (defaultRoutes.length) {
+    defaultRoutes.push({
+      status: 404,
+      src: '/api(\\/.*)?$',
+    });
+  }
+
+  return { defaultRoutes, error: null };
+}
+
+function hasPublicBuilder(builders: Builder[]): boolean {
+  return builders.some(
+    builder =>
+      builder.use === '@now/static' &&
+      builder.src === 'public/**/*' &&
+      builder.config &&
+      builder.config.zeroConfig === true
+  );
+}
+
+export async function detectRoutes(
+  files: string[],
+  builders: Builder[]
+): Promise<RoutesResult> {
+  const routesResult = await detectApiRoutes(files);
+
+  if (routesResult.defaultRoutes && hasPublicBuilder(builders)) {
+    routesResult.defaultRoutes.push({
+      src: '/(.*)',
+      dest: '/public/$1',
+    });
+  }
+
+  return routesResult;
+}

packages/now-build-utils/src/file-fs-ref.ts

@@ -31,7 +31,10 @@ class FileFsRef implements File {
     this.fsPath = fsPath;
   }
 
-  static async fromFsPath({ mode, fsPath }: FileFsRefOptions): Promise<FileFsRef> {
+  static async fromFsPath({
+    mode,
+    fsPath,
+  }: FileFsRefOptions): Promise<FileFsRef> {
     let m = mode;
     if (!m) {
       const stat = await fs.lstat(fsPath);
@@ -40,7 +43,11 @@ class FileFsRef implements File {
     return new FileFsRef({ mode: m, fsPath });
   }
 
-  static async fromStream({ mode = 0o100644, stream, fsPath }: FromStreamOptions): Promise<FileFsRef> {
+  static async fromStream({
+    mode = 0o100644,
+    stream,
+    fsPath,
+  }: FromStreamOptions): Promise<FileFsRef> {
     assert(typeof mode === 'number');
     assert(typeof stream.pipe === 'function'); // is-stream
     assert(typeof fsPath === 'string');
@@ -48,7 +55,7 @@ class FileFsRef implements File {
 
     await new Promise<void>((resolve, reject) => {
       const dest = fs.createWriteStream(fsPath, {
-        mode: mode & 0o777
+        mode: mode & 0o777,
       });
       stream.pipe(dest);
       stream.on('error', reject);
@@ -72,15 +79,15 @@ class FileFsRef implements File {
     let flag = false;
 
     // eslint-disable-next-line consistent-return
-    return multiStream((cb) => {
+    return multiStream(cb => {
       if (flag) return cb(null, null);
       flag = true;
 
       this.toStreamAsync()
-        .then((stream) => {
+        .then(stream => {
           cb(null, stream);
         })
-        .catch((error) => {
+        .catch(error => {
           cb(error, null);
         });
     });

packages/now-build-utils/src/file-ref.ts

@@ -8,7 +8,6 @@ import { File } from './types';
 interface FileRefOptions {
   mode?: number;
   digest: string;
-  mutable?: boolean;
 }
 
 const semaToDownloadFromS3 = new Sema(5);
@@ -26,26 +25,29 @@ export default class FileRef implements File {
   public type: 'FileRef';
   public mode: number;
   public digest: string;
-  public mutable: boolean;
 
-  constructor({ mode = 0o100644, digest, mutable = false }: FileRefOptions) {
+  constructor({ mode = 0o100644, digest }: FileRefOptions) {
     assert(typeof mode === 'number');
     assert(typeof digest === 'string');
-    assert(typeof mutable === 'boolean');
     this.type = 'FileRef';
     this.mode = mode;
     this.digest = digest;
-    this.mutable = mutable;
   }
 
   async toStreamAsync(): Promise<NodeJS.ReadableStream> {
     let url = '';
     // sha:24be087eef9fac01d61b30a725c1a10d7b45a256
-    const digestParts = this.digest.split(':');
+    const [digestType, digestHash] = this.digest.split(':');
-    if (digestParts[0] === 'sha') {
+    if (digestType === 'sha') {
-      url = this.mutable
+      // This CloudFront URL edge caches the `now-files` S3 bucket to prevent
-        ? `https://s3.amazonaws.com/now-files/${digestParts[1]}`
+      // overloading it
-        : `https://dmmcy0pwk6bqi.cloudfront.net/${digestParts[1]}`;
+      // `https://now-files.s3.amazonaws.com/${digestHash}`
+      url = `https://dmmcy0pwk6bqi.cloudfront.net/${digestHash}`;
+    } else if (digestType === 'sha+ephemeral') {
+      // This URL is currently only used for cache files that constantly
+      // change. We shouldn't cache it on CloudFront because it'd always be a
+      // MISS.
+      url = `https://now-ephemeral-files.s3.amazonaws.com/${digestHash}`;
     } else {
       throw new Error('Expected digest to be sha');
     }
@@ -58,14 +60,14 @@ export default class FileRef implements File {
           const resp = await fetch(url);
           if (!resp.ok) {
             const error = new BailableError(
-              `download: ${resp.status} ${resp.statusText} for ${url}`,
+              `download: ${resp.status} ${resp.statusText} for ${url}`
             );
             if (resp.status === 403) error.bail = true;
             throw error;
           }
           return resp.body;
         },
-        { factor: 1, retries: 3 },
+        { factor: 1, retries: 3 }
       );
     } finally {
       // console.timeEnd(`downloading ${url}`);
@@ -77,15 +79,15 @@ export default class FileRef implements File {
     let flag = false;
 
     // eslint-disable-next-line consistent-return
-    return multiStream((cb) => {
+    return multiStream(cb => {
       if (flag) return cb(null, null);
       flag = true;
 
       this.toStreamAsync()
-        .then((stream) => {
+        .then(stream => {
           cb(null, stream);
         })
-        .catch((error) => {
+        .catch(error => {
           cb(error, null);
         });
     });

packages/now-build-utils/src/fs/download.ts

@@ -4,11 +4,11 @@ import { File, Files, Meta } from '../types';
 import { remove, mkdirp, readlink, symlink } from 'fs-extra';
 
 export interface DownloadedFiles {
-  [filePath: string]: FileFsRef
+  [filePath: string]: FileFsRef;
 }
 
-const S_IFMT = 61440;   /* 0170000 type of file */
+const S_IFMT = 61440; /* 0170000 type of file */
-const S_IFLNK = 40960;  /* 0120000 symbolic link */
+const S_IFLNK = 40960; /* 0120000 symbolic link */
 
 export function isSymbolicLink(mode: number): boolean {
   return (mode & S_IFMT) === S_IFLNK;
@@ -17,9 +17,9 @@ export function isSymbolicLink(mode: number): boolean {
 async function downloadFile(file: File, fsPath: string): Promise<FileFsRef> {
   const { mode } = file;
   if (mode && isSymbolicLink(mode) && file.type === 'FileFsRef') {
-    const [ target ] = await Promise.all([
+    const [target] = await Promise.all([
       readlink((file as FileFsRef).fsPath),
-      mkdirp(path.dirname(fsPath))
+      mkdirp(path.dirname(fsPath)),
     ]);
     await symlink(target, fsPath);
     return FileFsRef.fromFsPath({ mode, fsPath });
@@ -34,12 +34,25 @@ async function removeFile(basePath: string, fileMatched: string) {
   await remove(file);
 }
 
-export default async function download(files: Files, basePath: string, meta?: Meta): Promise<DownloadedFiles> {
+export default async function download(
+  files: Files,
+  basePath: string,
+  meta?: Meta
+): Promise<DownloadedFiles> {
+  const { isDev = false, skipDownload = false, filesChanged = null, filesRemoved = null } =
+    meta || {};
+
+  if (isDev || skipDownload) {
+    // In `now dev`, the `download()` function is a no-op because
+    // the `basePath` matches the `cwd` of the dev server, so the
+    // source files are already available.
+    return files as DownloadedFiles;
+  }
+
   const files2: DownloadedFiles = {};
-  const { filesChanged = null, filesRemoved = null } = meta || {};
 
   await Promise.all(
-    Object.keys(files).map(async (name) => {
+    Object.keys(files).map(async name => {
       // If the file does not exist anymore, remove it.
       if (Array.isArray(filesRemoved) && filesRemoved.includes(name)) {
         await removeFile(basePath, name);
@@ -55,7 +68,7 @@ export default async function download(files: Files, basePath: string, meta?: Me
       const fsPath = path.join(basePath, name);
 
       files2[name] = await downloadFile(file, fsPath);
-    }),
+    })
   );
 
   return files2;

packages/now-build-utils/src/fs/glob.ts

@@ -8,12 +8,16 @@ import FileFsRef from '../file-fs-ref';
 type GlobOptions = vanillaGlob_.IOptions;
 
 interface FsFiles {
-  [filePath: string]: FileFsRef
+  [filePath: string]: FileFsRef;
 }
 
 const vanillaGlob = promisify(vanillaGlob_);
 
-export default async function glob(pattern: string, opts: GlobOptions | string, mountpoint?: string): Promise<FsFiles> {
+export default async function glob(
+  pattern: string,
+  opts: GlobOptions | string,
+  mountpoint?: string
+): Promise<FsFiles> {
   let options: GlobOptions;
   if (typeof opts === 'string') {
     options = { cwd: opts };
@@ -23,7 +27,7 @@ export default async function glob(pattern: string, opts: GlobOptions | string,
 
   if (!options.cwd) {
     throw new Error(
-      'Second argument (basePath) must be specified for names of resulting files',
+      'Second argument (basePath) must be specified for names of resulting files'
     );
   }
 
@@ -41,11 +45,11 @@ export default async function glob(pattern: string, opts: GlobOptions | string,
   const files = await vanillaGlob(pattern, options);
 
   for (const relativePath of files) {
-    const fsPath = path.join(options.cwd!, relativePath);
+    const fsPath = path.join(options.cwd!, relativePath).replace(/\\/g, '/');
     let stat: Stats = options.statCache![fsPath] as Stats;
     assert(
       stat,
-      `statCache does not contain value for ${relativePath} (resolved to ${fsPath})`,
+      `statCache does not contain value for ${relativePath} (resolved to ${fsPath})`
     );
     if (stat.isFile()) {
       const isSymlink = options.symlinks![fsPath];

packages/now-build-utils/src/fs/node-version.ts

@@ -0,0 +1,53 @@
+import { intersects } from 'semver';
+import { NodeVersion } from '../types';
+
+const supportedOptions: NodeVersion[] = [
+  { major: 10, range: '10.x', runtime: 'nodejs10.x' },
+  { major: 8, range: '8.10.x', runtime: 'nodejs8.10' },
+];
+
+// This version should match Fargate's default in the PATH
+// Today that is Node 8
+export const defaultSelection = supportedOptions.find(
+  o => o.major === 8
+) as NodeVersion;
+
+export async function getSupportedNodeVersion(
+  engineRange?: string,
+  silent?: boolean
+): Promise<NodeVersion> {
+  let selection = defaultSelection;
+
+  if (!engineRange) {
+    if (!silent) {
+      console.log(
+        'missing `engines` in `package.json`, using default range: ' +
+          selection.range
+      );
+    }
+  } else {
+    const found = supportedOptions.some(o => {
+      // the array is already in order so return the first
+      // match which will be the newest version of node
+      selection = o;
+      return intersects(o.range, engineRange);
+    });
+    if (found) {
+      if (!silent) {
+        console.log(
+          'Found `engines` in `package.json`, selecting range: ' +
+            selection.range
+        );
+      }
+    } else {
+      if (!silent) {
+        throw new Error(
+          'found `engines` in `package.json` with an unsupported node range: ' +
+            engineRange +
+            '\nplease use `10.x` or `8.10.x` instead'
+        );
+      }
+    }
+  }
+  return selection;
+}

packages/now-build-utils/src/fs/rename.ts

@@ -7,6 +7,6 @@ export default function rename(files: Files, delegate: Delegate): Files {
       ...newFiles,
       [delegate(name)]: files[name],
     }),
-    {},
+    {}
   );
 }

packages/now-build-utils/src/fs/run-user-scripts.ts

@@ -1,22 +1,31 @@
 import assert from 'assert';
 import fs from 'fs-extra';
 import path from 'path';
-import { spawn, SpawnOptions } from 'child_process';
+import spawn from 'cross-spawn';
+import { SpawnOptions } from 'child_process';
+import { deprecate } from 'util';
+import { Meta, PackageJson, NodeVersion, Config } from '../types';
+import { getSupportedNodeVersion } from './node-version';
 
-function spawnAsync(command: string, args: string[], cwd: string, opts: SpawnOptions = {}) {
+function spawnAsync(
+  command: string,
+  args: string[],
+  cwd: string,
+  opts: SpawnOptions = {}
+) {
   return new Promise<void>((resolve, reject) => {
-    const stderrLogs: Buffer[] = []
+    const stderrLogs: Buffer[] = [];
     opts = { stdio: 'inherit', cwd, ...opts };
     const child = spawn(command, args, opts);
 
-    if (opts.stdio === 'pipe'){
+    if (opts.stdio === 'pipe' && child.stderr) {
       child.stderr.on('data', data => stderrLogs.push(data));
     }
 
     child.on('error', reject);
     child.on('close', (code, signal) => {
       if (code === 0) {
-        return resolve()
+        return resolve();
       }
 
       const errorLogs = stderrLogs.map(line => line.toString()).join('');
@@ -37,19 +46,59 @@ async function chmodPlusX(fsPath: string) {
   await fs.chmod(fsPath, base8);
 }
 
-export async function runShellScript(fsPath: string) {
+export async function runShellScript(
+  fsPath: string,
+  args: string[] = [],
+  spawnOpts?: SpawnOptions
+) {
   assert(path.isAbsolute(fsPath));
   const destPath = path.dirname(fsPath);
   await chmodPlusX(fsPath);
-  await spawnAsync(`./${path.basename(fsPath)}`, [], destPath);
+  await spawnAsync(`./${path.basename(fsPath)}`, args, destPath, spawnOpts);
   return true;
 }
 
-async function scanParentDirs(destPath: string, scriptName?: string) {
+export function getSpawnOptions(
+  meta: Meta,
+  nodeVersion: NodeVersion
+): SpawnOptions {
+  const opts = {
+    env: { ...process.env },
+  };
+
+  if (!meta.isDev) {
+    opts.env.PATH = `/node${nodeVersion.major}/bin:${opts.env.PATH}`;
+  }
+
+  return opts;
+}
+
+export async function getNodeVersion(
+  destPath: string,
+  minNodeVersion?: string,
+  config?: Config
+): Promise<NodeVersion> {
+  const { packageJson } = await scanParentDirs(destPath, true);
+  let range: string | undefined;
+  let silent = false;
+  if (packageJson && packageJson.engines && packageJson.engines.node) {
+    range = packageJson.engines.node;
+  } else if (minNodeVersion) {
+    range = minNodeVersion;
+    silent = true;
+  } else if (config && config.zeroConfig) {
+    // Use latest node version zero config detected
+    range = '10.x';
+    silent = true;
+  }
+  return getSupportedNodeVersion(range, silent);
+}
+
+async function scanParentDirs(destPath: string, readPackageJson = false) {
   assert(path.isAbsolute(destPath));
 
-  let hasScript = false;
   let hasPackageLockJson = false;
+  let packageJson: PackageJson | undefined;
   let currentDestPath = destPath;
 
   // eslint-disable-next-line no-constant-condition
@@ -58,13 +107,12 @@ async function scanParentDirs(destPath: string, scriptName?: string) {
     // eslint-disable-next-line no-await-in-loop
     if (await fs.pathExists(packageJsonPath)) {
       // eslint-disable-next-line no-await-in-loop
-      const packageJson = JSON.parse(await fs.readFile(packageJsonPath, 'utf8'));
+      if (readPackageJson) {
-      hasScript = Boolean(
+        packageJson = JSON.parse(await fs.readFile(packageJsonPath, 'utf8'));
-        packageJson.scripts && scriptName && packageJson.scripts[scriptName],
+      }
-      );
       // eslint-disable-next-line no-await-in-loop
       hasPackageLockJson = await fs.pathExists(
-        path.join(currentDestPath, 'package-lock.json'),
+        path.join(currentDestPath, 'package-lock.json')
       );
       break;
     }
@@ -74,40 +122,36 @@ async function scanParentDirs(destPath: string, scriptName?: string) {
     currentDestPath = newDestPath;
   }
 
-  return { hasScript, hasPackageLockJson };
+  return { hasPackageLockJson, packageJson };
 }
 
-export async function installDependencies(destPath: string, args: string[] = []) {
+export async function runNpmInstall(
+  destPath: string,
+  args: string[] = [],
+  spawnOpts?: SpawnOptions
+) {
   assert(path.isAbsolute(destPath));
 
   let commandArgs = args;
   console.log(`installing to ${destPath}`);
   const { hasPackageLockJson } = await scanParentDirs(destPath);
 
-  const opts = {
+  const opts = spawnOpts || { env: process.env };
-    env: {
-      ...process.env,
-      // This is a little hack to force `node-gyp` to build for the
-      // Node.js version that `@now/node` and `@now/node-server` use
-      npm_config_target: '8.10.0',
-    },
-    stdio: 'pipe'
-  };
 
   if (hasPackageLockJson) {
     commandArgs = args.filter(a => a !== '--prefer-offline');
     await spawnAsync(
       'npm',
-      ['install'].concat(commandArgs),
+      commandArgs.concat(['install', '--unsafe-perm']),
       destPath,
-      opts as SpawnOptions
+      opts
     );
   } else {
     await spawnAsync(
       'yarn',
-      ['--cwd', destPath].concat(commandArgs),
+      commandArgs.concat(['--ignore-engines', '--cwd', destPath]),
       destPath,
-      opts as SpawnOptions,
+      opts
     );
   }
 }
@@ -118,9 +162,15 @@ export async function runPackageJsonScript(
   opts?: SpawnOptions
 ) {
   assert(path.isAbsolute(destPath));
-  const { hasScript, hasPackageLockJson } = await scanParentDirs(
+  const { packageJson, hasPackageLockJson } = await scanParentDirs(
     destPath,
-    scriptName,
+    true
+  );
+  const hasScript = Boolean(
+    packageJson &&
+      packageJson.scripts &&
+      scriptName &&
+      packageJson.scripts[scriptName]
   );
   if (!hasScript) return false;
 
@@ -129,10 +179,22 @@ export async function runPackageJsonScript(
     await spawnAsync('npm', ['run', scriptName], destPath, opts);
   } else {
     console.log(`running "yarn run ${scriptName}"`);
-    await spawnAsync('yarn', ['--cwd', destPath, 'run', scriptName], destPath, opts);
+    await spawnAsync(
+      'yarn',
+      ['--cwd', destPath, 'run', scriptName],
+      destPath,
+      opts
+    );
   }
 
   return true;
 }
 
-export const runNpmInstall = installDependencies;
+/**
+ * @deprecate installDependencies() is deprecated.
+ * Please use runNpmInstall() instead.
+ */
+export const installDependencies = deprecate(
+  runNpmInstall,
+  'installDependencies() is deprecated. Please use runNpmInstall() instead.'
+);

packages/now-build-utils/src/fs/stream-to-buffer.ts

@@ -1,26 +1,28 @@
 import eos from 'end-of-stream';
 
-export default function streamToBuffer(stream: NodeJS.ReadableStream): Promise<Buffer> {
+export default function streamToBuffer(
+  stream: NodeJS.ReadableStream
+): Promise<Buffer> {
   return new Promise<Buffer>((resolve, reject) => {
     const buffers: Buffer[] = [];
 
-    stream.on('data', buffers.push.bind(buffers))
+    stream.on('data', buffers.push.bind(buffers));
 
-    eos(stream, (err) => {
+    eos(stream, err => {
-        if (err) {
+      if (err) {
-          reject(err);
+        reject(err);
-          return;
+        return;
-        }
+      }
-        switch (buffers.length) {
+      switch (buffers.length) {
-          case 0:
+        case 0:
-            resolve(Buffer.allocUnsafe(0));
+          resolve(Buffer.allocUnsafe(0));
-            break;
+          break;
-          case 1:
+        case 1:
-            resolve(buffers[0]);
+          resolve(buffers[0]);
-            break;
+          break;
-          default:
+        default:
-            resolve(Buffer.concat(buffers));
+          resolve(Buffer.concat(buffers));
-        }
+      }
     });
   });
-}
+}

packages/now-build-utils/src/index.ts

@@ -1,34 +1,47 @@
 import FileBlob from './file-blob';
 import FileFsRef from './file-fs-ref';
 import FileRef from './file-ref';
-import { File, Files, AnalyzeOptions, BuildOptions, PrepareCacheOptions, ShouldServeOptions, Meta } from './types';
 import { Lambda, createLambda } from './lambda';
-import download from './fs/download';
+import download, { DownloadedFiles } from './fs/download';
-import getWriteableDirectory from './fs/get-writable-directory'
+import getWriteableDirectory from './fs/get-writable-directory';
 import glob from './fs/glob';
 import rename from './fs/rename';
-import { installDependencies, runPackageJsonScript, runNpmInstall, runShellScript } from './fs/run-user-scripts';
+import {
+  installDependencies,
+  runPackageJsonScript,
+  runNpmInstall,
+  runShellScript,
+  getNodeVersion,
+  getSpawnOptions,
+} from './fs/run-user-scripts';
 import streamToBuffer from './fs/stream-to-buffer';
 import shouldServe from './should-serve';
+import { detectBuilders } from './detect-builders';
+import { detectRoutes } from './detect-routes';
+import debug from './debug';
 
 export {
-    FileBlob,
+  FileBlob,
-    FileFsRef,
+  FileFsRef,
-    FileRef,
+  FileRef,
-    Files,
+  Lambda,
-    File,
+  createLambda,
-    Meta,
+  download,
-    Lambda,
+  DownloadedFiles,
-    createLambda,
+  getWriteableDirectory,
-    download,
+  glob,
-    getWriteableDirectory,
+  rename,
-    glob,
+  installDependencies,
-    rename,
+  runPackageJsonScript,
-    installDependencies, runPackageJsonScript, runNpmInstall, runShellScript,
+  runNpmInstall,
-    streamToBuffer,
+  runShellScript,
-    AnalyzeOptions,
+  getNodeVersion,
-    BuildOptions,
+  getSpawnOptions,
-    PrepareCacheOptions,
+  streamToBuffer,
-    ShouldServeOptions,
+  shouldServe,
-    shouldServe,
+  detectBuilders,
+  detectRoutes,
+  debug,
 };
+
+export * from './types';

packages/now-build-utils/src/lambda.ts

@@ -32,9 +32,7 @@ export class Lambda {
   public runtime: string;
   public environment: Environment;
 
-  constructor({
+  constructor({ zipBuffer, handler, runtime, environment }: LambdaOptions) {
-    zipBuffer, handler, runtime, environment,
-  }: LambdaOptions) {
     this.type = 'Lambda';
     this.zipBuffer = zipBuffer;
     this.handler = handler;
@@ -47,7 +45,10 @@ const sema = new Sema(10);
 const mtime = new Date(1540000000000);
 
 export async function createLambda({
-  files, handler, runtime, environment = {},
+  files,
+  handler,
+  runtime,
+  environment = {},
 }: CreateLambdaOptions): Promise<Lambda> {
   assert(typeof files === 'object', '"files" must be an object');
   assert(typeof handler === 'string', '"handler" is not a string');
@@ -97,7 +98,9 @@ export async function createZip(files: Files): Promise<Buffer> {
     }
 
     zipFile.end();
-    streamToBuffer(zipFile.outputStream).then(resolve).catch(reject);
+    streamToBuffer(zipFile.outputStream)
+      .then(resolve)
+      .catch(reject);
   });
 
   return zipBuffer;

packages/now-build-utils/src/should-serve.ts

@@ -5,7 +5,7 @@ import FileFsRef from './file-fs-ref';
 export default function shouldServe({
   entrypoint,
   files,
-  requestPath
+  requestPath,
 }: ShouldServeOptions): boolean {
   requestPath = requestPath.replace(/\/$/, ''); // sanitize trailing '/'
   entrypoint = entrypoint.replace(/\\/, '/'); // windows compatibility
@@ -23,5 +23,5 @@ export default function shouldServe({
 }
 
 function hasProp(obj: { [path: string]: FileFsRef }, key: string): boolean {
-  return Object.hasOwnProperty.call(obj, key)
+  return Object.hasOwnProperty.call(obj, key);
 }

packages/now-build-utils/src/types.ts

@@ -5,6 +5,9 @@ export interface File {
   type: string;
   mode: number;
   toStream: () => NodeJS.ReadableStream;
+  /**
+   * The absolute path to the file in the filesystem
+   */
   fsPath?: string;
 }
 
@@ -12,12 +15,40 @@ export interface Files {
   [filePath: string]: File;
 }
 
+export interface Route {
+  src?: string;
+  dest?: string;
+  handle?: string;
+  type?: string;
+  headers?: {
+    [key: string]: string;
+  };
+  continue?: boolean;
+  status?: number;
+}
+
 export interface Config {
-  [key: string]: string;
+  [key: string]:
+    | string
+    | string[]
+    | boolean
+    | number
+    | { [key: string]: string }
+    | undefined;
+  maxLambdaSize?: string;
+  includeFiles?: string | string[];
+  bundle?: boolean;
+  ldsflags?: string;
+  helpers?: boolean;
+  rust?: string;
+  debug?: boolean;
+  zeroConfig?: boolean;
+  import?: { [key: string]: string };
 }
 
 export interface Meta {
   isDev?: boolean;
+  skipDownload?: boolean;
   requestPath?: string;
   filesChanged?: string[];
   filesRemoved?: string[];
@@ -152,3 +183,34 @@ export interface ShouldServeOptions {
    */
   config: Config;
 }
+
+export interface PackageJson {
+  name: string;
+  version: string;
+  engines?: {
+    [key: string]: string;
+    node: string;
+    npm: string;
+  };
+  scripts?: {
+    [key: string]: string;
+  };
+  dependencies?: {
+    [key: string]: string;
+  };
+  devDependencies?: {
+    [key: string]: string;
+  };
+}
+
+export interface NodeVersion {
+  major: number;
+  range: string;
+  runtime: string;
+}
+
+export interface Builder {
+  use: string;
+  src: string;
+  config?: Config;
+}

packages/now-build-utils/test/fixtures/07-cross-install/now.json

@@ -1,9 +1,10 @@
 {
   "version": 2,
-  "builds": [
+  "builds": [{ "src": "api/index.js", "use": "@now/node" }],
-    { "src": "api/index.js", "use": "@now/node" }
-  ],
   "probes": [
-    { "path": "/api/index.js", "mustContain": "cross-cow:RANDOMNESS_PLACEHOLDER" }
+    {
+      "path": "/api/index.js",
+      "mustContain": "cross-cow:RANDOMNESS_PLACEHOLDER"
+    }
   ]
 }

packages/now-build-utils/test/fixtures/15-yarn-ignore-engines/index.js

@@ -0,0 +1,9 @@
+const scheduler = require('@google-cloud/scheduler');
+
+module.exports = (_, res) => {
+  if (scheduler) {
+    res.end('found:RANDOMNESS_PLACEHOLDER');
+  } else {
+    res.end('nope:RANDOMNESS_PLACEHOLDER');
+  }
+};

packages/now-build-utils/test/fixtures/15-yarn-ignore-engines/now.json

@@ -0,0 +1,10 @@
+{
+  "version": 2,
+  "builds": [
+    {
+      "src": "index.js",
+      "use": "@now/node"
+    }
+  ],
+  "probes": [{ "path": "/", "mustContain": "found:RANDOMNESS_PLACEHOLDER" }]
+}

packages/now-build-utils/test/fixtures/15-yarn-ignore-engines/package.json

@@ -0,0 +1,8 @@
+{
+  "name": "15-yarn-ignore-engines",
+  "version": "1.0.0",
+  "main": "index.js",
+  "dependencies": {
+    "@google-cloud/scheduler": "0.3.0"
+  }
+}

packages/now-build-utils/test/test.js

@@ -4,8 +4,14 @@ const fs = require('fs-extra');
 // eslint-disable-next-line import/no-extraneous-dependencies
 const execa = require('execa');
 const assert = require('assert');
-const { glob, download } = require('../');
+const {
+  glob, download, detectBuilders, detectRoutes,
+} = require('../');
 const { createZip } = require('../dist/lambda');
+const {
+  getSupportedNodeVersion,
+  defaultSelection,
+} = require('../dist/fs/node-version');
 
 const {
   packAndDeploy,
@@ -64,6 +70,82 @@ it('should create zip files with symlinks properly', async () => {
   assert(aStat.isFile());
 });
 
+it('should only match supported node versions', () => {
+  expect(getSupportedNodeVersion('10.x')).resolves.toHaveProperty('major', 10);
+  expect(getSupportedNodeVersion('8.10.x')).resolves.toHaveProperty('major', 8);
+  expect(getSupportedNodeVersion('8.11.x')).rejects.toThrow();
+  expect(getSupportedNodeVersion('6.x')).rejects.toThrow();
+  expect(getSupportedNodeVersion('999.x')).rejects.toThrow();
+  expect(getSupportedNodeVersion('foo')).rejects.toThrow();
+  expect(getSupportedNodeVersion('')).resolves.toBe(defaultSelection);
+  expect(getSupportedNodeVersion(null)).resolves.toBe(defaultSelection);
+  expect(getSupportedNodeVersion(undefined)).resolves.toBe(defaultSelection);
+});
+
+it('should match all semver ranges', () => {
+  // See https://docs.npmjs.com/files/package.json#engines
+  expect(getSupportedNodeVersion('10.0.0')).resolves.toHaveProperty(
+    'major',
+    10,
+  );
+  expect(getSupportedNodeVersion('10.x')).resolves.toHaveProperty('major', 10);
+  expect(getSupportedNodeVersion('>=10')).resolves.toHaveProperty('major', 10);
+  expect(getSupportedNodeVersion('>=10.3.0')).resolves.toHaveProperty(
+    'major',
+    10,
+  );
+  expect(getSupportedNodeVersion('8.5.0 - 10.5.0')).resolves.toHaveProperty(
+    'major',
+    10,
+  );
+  expect(getSupportedNodeVersion('>=9.0.0')).resolves.toHaveProperty(
+    'major',
+    10,
+  );
+  expect(getSupportedNodeVersion('>=9.5.0 <=10.5.0')).resolves.toHaveProperty(
+    'major',
+    10,
+  );
+  expect(getSupportedNodeVersion('~10.5.0')).resolves.toHaveProperty(
+    'major',
+    10,
+  );
+  expect(getSupportedNodeVersion('^10.5.0')).resolves.toHaveProperty(
+    'major',
+    10,
+  );
+});
+
+it('should support require by path for legacy builders', () => {
+  const index = require('@now/build-utils');
+
+  const download2 = require('@now/build-utils/fs/download.js');
+  const getWriteableDirectory2 = require('@now/build-utils/fs/get-writable-directory.js');
+  const glob2 = require('@now/build-utils/fs/glob.js');
+  const rename2 = require('@now/build-utils/fs/rename.js');
+  const {
+    runNpmInstall: runNpmInstall2,
+  } = require('@now/build-utils/fs/run-user-scripts.js');
+  const streamToBuffer2 = require('@now/build-utils/fs/stream-to-buffer.js');
+
+  const FileBlob2 = require('@now/build-utils/file-blob.js');
+  const FileFsRef2 = require('@now/build-utils/file-fs-ref.js');
+  const FileRef2 = require('@now/build-utils/file-ref.js');
+  const { Lambda: Lambda2 } = require('@now/build-utils/lambda.js');
+
+  expect(download2).toBe(index.download);
+  expect(getWriteableDirectory2).toBe(index.getWriteableDirectory);
+  expect(glob2).toBe(index.glob);
+  expect(rename2).toBe(index.rename);
+  expect(runNpmInstall2).toBe(index.runNpmInstall);
+  expect(streamToBuffer2).toBe(index.streamToBuffer);
+
+  expect(FileBlob2).toBe(index.FileBlob);
+  expect(FileFsRef2).toBe(index.FileFsRef);
+  expect(FileRef2).toBe(index.FileRef);
+  expect(Lambda2).toBe(index.Lambda);
+});
+
 // own fixtures
 
 const fixturesPath = path.resolve(__dirname, 'fixtures');
@@ -83,7 +165,7 @@ for (const fixture of fs.readdirSync(fixturesPath)) {
 
 // few foreign tests
 
-const buildersToTestWith = ['now-node-server', 'now-static-build'];
+const buildersToTestWith = ['now-next', 'now-node', 'now-static-build'];
 
 // eslint-disable-next-line no-restricted-syntax
 for (const builder of buildersToTestWith) {
@@ -95,7 +177,7 @@ for (const builder of buildersToTestWith) {
   // eslint-disable-next-line no-restricted-syntax
   for (const fixture of fs.readdirSync(fixturesPath2)) {
     // don't run all foreign fixtures, just some
-    if (['01-cowsay', '03-env-vars'].includes(fixture)) {
+    if (['01-cowsay', '01-cache-headers', '03-env-vars'].includes(fixture)) {
       // eslint-disable-next-line no-loop-func
       it(`should build ${builder}/${fixture}`, async () => {
         await expect(
@@ -108,3 +190,400 @@ for (const builder of buildersToTestWith) {
     }
   }
 }
+
+it('Test `detectBuilders`', async () => {
+  {
+    // package.json + no build
+    const pkg = { dependencies: { next: '9.0.0' } };
+    const files = ['package.json', 'pages/index.js', 'public/index.html'];
+    const { builders, errors } = await detectBuilders(files, pkg);
+    expect(builders).toBe(null);
+    expect(errors.length).toBe(1);
+  }
+
+  {
+    // package.json + no build + next
+    const pkg = {
+      scripts: { build: 'next build' },
+      dependencies: { next: '9.0.0' },
+    };
+    const files = ['package.json', 'pages/index.js'];
+    const { builders, errors } = await detectBuilders(files, pkg);
+    expect(builders[0].use).toBe('@now/next');
+    expect(errors).toBe(null);
+  }
+
+  {
+    // package.json + no build + next
+    const pkg = {
+      scripts: { build: 'next build' },
+      devDependencies: { next: '9.0.0' },
+    };
+    const files = ['package.json', 'pages/index.js'];
+    const { builders, errors } = await detectBuilders(files, pkg);
+    expect(builders[0].use).toBe('@now/next');
+    expect(errors).toBe(null);
+  }
+
+  {
+    // package.json + no build
+    const pkg = {};
+    const files = ['package.json'];
+    const { builders, errors } = await detectBuilders(files, pkg);
+    expect(builders).toBe(null);
+    expect(errors.length).toBe(1);
+  }
+
+  {
+    // static file
+    const files = ['index.html'];
+    const { builders, errors } = await detectBuilders(files);
+    expect(builders).toBe(null);
+    expect(errors).toBe(null);
+  }
+
+  {
+    // no package.json + public
+    const files = ['api/users.js', 'public/index.html'];
+    const { builders, errors } = await detectBuilders(files);
+    expect(builders[1].use).toBe('@now/static');
+    expect(errors).toBe(null);
+  }
+
+  {
+    // no package.json + no build + raw static + api
+    const files = ['api/users.js', 'index.html'];
+    const { builders, errors } = await detectBuilders(files);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/users.js');
+    expect(builders[1].use).toBe('@now/static');
+    expect(builders[1].src).toBe('index.html');
+    expect(builders.length).toBe(2);
+    expect(errors).toBe(null);
+  }
+
+  {
+    // package.json + no build + root + api
+    const files = ['index.html', 'api/[endpoint].js', 'static/image.png'];
+    const { builders, errors } = await detectBuilders(files);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/[endpoint].js');
+    expect(builders[1].use).toBe('@now/static');
+    expect(builders[1].src).toBe('index.html');
+    expect(builders[2].use).toBe('@now/static');
+    expect(builders[2].src).toBe('static/image.png');
+    expect(builders.length).toBe(3);
+    expect(errors).toBe(null);
+  }
+
+  {
+    // api + ignore files
+    const files = [
+      'api/_utils/handler.js',
+      'api/[endpoint]/.helper.js',
+      'api/[endpoint]/[id].js',
+    ];
+
+    const { builders } = await detectBuilders(files);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/[endpoint]/[id].js');
+    expect(builders.length).toBe(1);
+  }
+
+  {
+    // api + next + public
+    const pkg = {
+      scripts: { build: 'next build' },
+      devDependencies: { next: '9.0.0' },
+    };
+    const files = ['package.json', 'api/endpoint.js', 'public/index.html'];
+
+    const { builders } = await detectBuilders(files, pkg);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/endpoint.js');
+    expect(builders[1].use).toBe('@now/next');
+    expect(builders[1].src).toBe('package.json');
+    expect(builders.length).toBe(2);
+  }
+
+  {
+    // api + next + raw static
+    const pkg = {
+      scripts: { build: 'next build' },
+      devDependencies: { next: '9.0.0' },
+    };
+    const files = ['package.json', 'api/endpoint.js', 'index.html'];
+
+    const { builders } = await detectBuilders(files, pkg);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/endpoint.js');
+    expect(builders[1].use).toBe('@now/next');
+    expect(builders[1].src).toBe('package.json');
+    expect(builders.length).toBe(2);
+  }
+
+  {
+    // api + raw static
+    const files = ['api/endpoint.js', 'index.html', 'favicon.ico'];
+
+    const { builders } = await detectBuilders(files);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/endpoint.js');
+    expect(builders[1].use).toBe('@now/static');
+    expect(builders[1].src).toBe('favicon.ico');
+    expect(builders[2].use).toBe('@now/static');
+    expect(builders[2].src).toBe('index.html');
+    expect(builders.length).toBe(3);
+  }
+
+  {
+    // api + public
+    const files = [
+      'api/endpoint.js',
+      'public/index.html',
+      'public/favicon.ico',
+      'README.md',
+    ];
+
+    const { builders } = await detectBuilders(files);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/endpoint.js');
+    expect(builders[1].use).toBe('@now/static');
+    expect(builders[1].src).toBe('public/**/*');
+    expect(builders.length).toBe(2);
+  }
+
+  {
+    // just public
+    const files = ['public/index.html', 'public/favicon.ico', 'README.md'];
+
+    const { builders } = await detectBuilders(files);
+    expect(builders[0].src).toBe('public/**/*');
+    expect(builders.length).toBe(1);
+  }
+
+  {
+    // next + public
+    const pkg = {
+      scripts: { build: 'next build' },
+      devDependencies: { next: '9.0.0' },
+    };
+    const files = ['package.json', 'public/index.html', 'README.md'];
+
+    const { builders } = await detectBuilders(files, pkg);
+    expect(builders[0].use).toBe('@now/next');
+    expect(builders[0].src).toBe('package.json');
+    expect(builders.length).toBe(1);
+  }
+
+  {
+    // nuxt
+    const pkg = {
+      scripts: { build: 'nuxt build' },
+      dependencies: { nuxt: '2.8.1' },
+    };
+    const files = ['package.json', 'pages/index.js'];
+
+    const { builders } = await detectBuilders(files, pkg);
+    expect(builders[0].use).toBe('@now/static-build');
+    expect(builders[0].src).toBe('package.json');
+    expect(builders.length).toBe(1);
+  }
+
+  {
+    // package.json with no build + api
+    const pkg = { dependencies: { next: '9.0.0' } };
+    const files = ['package.json', 'api/[endpoint].js'];
+
+    const { builders } = await detectBuilders(files, pkg);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[0].src).toBe('api/[endpoint].js');
+    expect(builders.length).toBe(1);
+  }
+
+  {
+    // package.json with no build + public directory
+    const pkg = { dependencies: { next: '9.0.0' } };
+    const files = ['package.json', 'public/index.html'];
+
+    const { builders, errors } = await detectBuilders(files, pkg);
+    expect(builders).toBe(null);
+    expect(errors.length).toBe(1);
+  }
+
+  {
+    // no package.json + api
+    const files = ['api/[endpoint].js', 'api/[endpoint]/[id].js'];
+
+    const { builders } = await detectBuilders(files);
+    expect(builders.length).toBe(2);
+  }
+
+  {
+    // no package.json + no api
+    const files = ['index.html'];
+
+    const { builders, errors } = await detectBuilders(files);
+    expect(builders).toBe(null);
+    expect(errors).toBe(null);
+  }
+
+  {
+    // package.json + api + canary
+    const pkg = {
+      scripts: { build: 'next build' },
+      dependencies: { next: '9.0.0' },
+    };
+    const files = [
+      'pages/index.js',
+      'api/[endpoint].js',
+      'api/[endpoint]/[id].js',
+    ];
+
+    const { builders } = await detectBuilders(files, pkg, { tag: 'canary' });
+    expect(builders[0].use).toBe('@now/node@canary');
+    expect(builders[1].use).toBe('@now/node@canary');
+    expect(builders[2].use).toBe('@now/next@canary');
+    expect(builders.length).toBe(3);
+  }
+});
+
+it('Test `detectRoutes`', async () => {
+  {
+    const files = ['api/user.go', 'api/team.js', 'api/package.json'];
+
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+    expect(defaultRoutes.length).toBe(3);
+    expect(defaultRoutes[0].dest).toBe('/api/team.js');
+    expect(defaultRoutes[1].dest).toBe('/api/user.go');
+    expect(defaultRoutes[2].dest).not.toBeDefined();
+    expect(defaultRoutes[2].status).toBe(404);
+  }
+
+  {
+    const files = ['api/user.go', 'api/user.js'];
+
+    const { builders } = await detectBuilders(files);
+    const { error } = await detectRoutes(files, builders);
+    expect(error.code).toBe('conflicting_file_path');
+  }
+
+  {
+    const files = ['api/[user].go', 'api/[team]/[id].js'];
+
+    const { builders } = await detectBuilders(files);
+    const { error } = await detectRoutes(files, builders);
+    expect(error.code).toBe('conflicting_file_path');
+  }
+
+  {
+    const files = ['api/[team]/[team].js'];
+
+    const { builders } = await detectBuilders(files);
+    const { error } = await detectRoutes(files, builders);
+    expect(error.code).toBe('conflicting_path_segment');
+  }
+
+  {
+    const files = ['api/date/index.js', 'api/date/index.go'];
+
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes, error } = await detectRoutes(files, builders);
+    expect(defaultRoutes).toBe(null);
+    expect(error.code).toBe('conflicting_file_path');
+  }
+
+  {
+    const files = ['api/[endpoint].js', 'api/[endpoint]/[id].js'];
+
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+    expect(defaultRoutes.length).toBe(3);
+  }
+
+  {
+    const files = [
+      'public/index.html',
+      'api/[endpoint].js',
+      'api/[endpoint]/[id].js',
+    ];
+
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+    expect(defaultRoutes[2].status).toBe(404);
+    expect(defaultRoutes[2].src).toBe('/api(\\/.*)?$');
+    expect(defaultRoutes[3].src).toBe('/(.*)');
+    expect(defaultRoutes[3].dest).toBe('/public/$1');
+    expect(defaultRoutes.length).toBe(4);
+  }
+
+  {
+    const pkg = {
+      scripts: { build: 'next build' },
+      devDependencies: { next: '9.0.0' },
+    };
+    const files = ['public/index.html', 'api/[endpoint].js'];
+
+    const { builders } = await detectBuilders(files, pkg);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+    expect(defaultRoutes[1].status).toBe(404);
+    expect(defaultRoutes[1].src).toBe('/api(\\/.*)?$');
+    expect(defaultRoutes.length).toBe(2);
+  }
+
+  {
+    const files = ['public/index.html'];
+
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+
+    expect(defaultRoutes.length).toBe(1);
+  }
+
+  {
+    const files = ['api/date/index.js', 'api/date.js'];
+
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+
+    expect(defaultRoutes.length).toBe(3);
+    expect(defaultRoutes[0].src).toBe('^/api/date/(index|index\\.js)?$');
+    expect(defaultRoutes[0].dest).toBe('/api/date/index.js');
+    expect(defaultRoutes[1].src).toBe('^/api/(date|date\\.js)$');
+    expect(defaultRoutes[1].dest).toBe('/api/date.js');
+  }
+
+  {
+    const files = ['api/date.js', 'api/[date]/index.js'];
+
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+
+    expect(defaultRoutes.length).toBe(3);
+    expect(defaultRoutes[0].src).toBe('^/api/([^\\/]+)/(index|index\\.js)?$');
+    expect(defaultRoutes[0].dest).toBe('/api/[date]/index.js?date=$1');
+    expect(defaultRoutes[1].src).toBe('^/api/(date|date\\.js)$');
+    expect(defaultRoutes[1].dest).toBe('/api/date.js');
+  }
+
+  {
+    const files = [
+      'api/index.ts',
+      'api/index.d.ts',
+      'api/users/index.ts',
+      'api/users/index.d.ts',
+      'api/food.ts',
+      'api/ts/gold.ts',
+    ];
+    const { builders } = await detectBuilders(files);
+    const { defaultRoutes } = await detectRoutes(files, builders);
+
+    expect(builders.length).toBe(4);
+    expect(builders[0].use).toBe('@now/node');
+    expect(builders[1].use).toBe('@now/node');
+    expect(builders[2].use).toBe('@now/node');
+    expect(builders[3].use).toBe('@now/node');
+    expect(defaultRoutes.length).toBe(5);
+  }
+});

packages/now-build-utils/tsconfig.json

@@ -15,10 +15,6 @@
     "strict": true,
     "target": "esnext"
   },
-  "include": [
+  "include": ["src/**/*"],
-    "src/**/*"
+  "exclude": ["node_modules"]
-  ],
-  "exclude": [
-    "node_modules"
-  ]
 }

packages/now-cgi/index.js

@@ -5,15 +5,17 @@ const glob = require('@now/build-utils/fs/glob'); // eslint-disable-line import/
 const download = require('@now/build-utils/fs/download'); // eslint-disable-line import/no-extraneous-dependencies
 const { createLambda } = require('@now/build-utils/lambda'); // eslint-disable-line import/no-extraneous-dependencies
 const getWritableDirectory = require('@now/build-utils/fs/get-writable-directory'); // eslint-disable-line import/no-extraneous-dependencies
+const { shouldServe } = require('@now/build-utils'); // eslint-disable-line import/no-extraneous-dependencies
 
 exports.analyze = ({ files, entrypoint }) => files[entrypoint].digest;
 
-exports.build = async ({ files, entrypoint }) => {
+exports.build = async ({
+  workPath, files, entrypoint, meta,
+}) => {
   console.log('downloading files...');
-  const srcDir = await getWritableDirectory();
   const outDir = await getWritableDirectory();
 
-  await download(files, srcDir);
+  await download(files, workPath, meta);
 
   const handlerPath = path.join(__dirname, 'handler');
   await copyFile(handlerPath, path.join(outDir, 'handler'));
@@ -23,7 +25,7 @@ exports.build = async ({ files, entrypoint }) => {
 
   // For now only the entrypoint file is copied into the lambda
   await copyFile(
-    path.join(srcDir, entrypoint),
+    path.join(workPath, entrypoint),
     path.join(outDir, entrypoint),
   );
 
@@ -40,3 +42,5 @@ exports.build = async ({ files, entrypoint }) => {
     [entrypoint]: lambda,
   };
 };
+
+exports.shouldServe = shouldServe;

packages/now-cgi/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@now/cgi",
-  "version": "0.1.0",
+  "version": "0.1.4",
   "license": "MIT",
   "repository": {
     "type": "git",

packages/now-go/.gitignore

@@ -1,5 +1,6 @@
 node_modules
+dist
 *.log
-/?.js
 /go
-/get-exported-function-name
+/analyze
+*.js

packages/now-go/build.sh

@@ -0,0 +1,2 @@
+ncc build index.ts -o dist
+ncc build install.ts -o dist/install

packages/now-go/go-helpers.js

@@ -1,129 +0,0 @@
-const tar = require('tar');
-const execa = require('execa');
-const fetch = require('node-fetch');
-const { mkdirp } = require('fs-extra');
-const { dirname, join } = require('path');
-const debug = require('debug')('@now/go:go-helpers');
-
-const archMap = new Map([['x64', 'amd64'], ['x86', '386']]);
-const platformMap = new Map([['win32', 'windows']]);
-
-// Location where the `go` binary will be installed after `postinstall`
-const GO_DIR = join(__dirname, 'go');
-const GO_BIN = join(GO_DIR, 'bin/go');
-
-const getPlatform = p => platformMap.get(p) || p;
-const getArch = a => archMap.get(a) || a;
-const getGoUrl = (version, platform, arch) => {
-  const goArch = getArch(arch);
-  const goPlatform = getPlatform(platform);
-  const ext = platform === 'win32' ? 'zip' : 'tar.gz';
-  return `https://dl.google.com/go/go${version}.${goPlatform}-${goArch}.${ext}`;
-};
-
-async function getExportedFunctionName(filePath) {
-  debug('Detecting handler name for %o', filePath);
-  const bin = join(__dirname, 'get-exported-function-name');
-  const args = [filePath];
-  const name = await execa.stdout(bin, args);
-  debug('Detected exported name %o', name);
-  return name;
-}
-
-// Creates a `$GOPATH` directory tree, as per `go help gopath` instructions.
-// Without this, `go` won't recognize the `$GOPATH`.
-function createGoPathTree(goPath, platform, arch) {
-  const tuple = `${getPlatform(platform)}_${getArch(arch)}`;
-  debug('Creating GOPATH directory structure for %o (%s)', goPath, tuple);
-  return Promise.all([
-    mkdirp(join(goPath, 'bin')),
-    mkdirp(join(goPath, 'pkg', tuple)),
-  ]);
-}
-
-async function get({ src } = {}) {
-  const args = ['get'];
-  if (src) {
-    debug('Fetching `go` dependencies for file %o', src);
-    args.push(src);
-  } else {
-    debug('Fetching `go` dependencies for cwd %o', this.cwd);
-  }
-  await this(...args);
-}
-
-async function build({ src, dest }) {
-  debug('Building `go` binary %o -> %o', src, dest);
-  let sources;
-  if (Array.isArray(src)) {
-    sources = src;
-  } else {
-    sources = [src];
-  }
-  await this('build', '-o', dest, ...sources);
-}
-
-async function createGo(
-  goPath,
-  platform = process.platform,
-  arch = process.arch,
-  opts = {},
-  goMod = false,
-) {
-  const env = {
-    ...process.env,
-    PATH: `${dirname(GO_BIN)}:${process.env.PATH}`,
-    GOPATH: goPath,
-    ...opts.env,
-  };
-
-  if (goMod) {
-    env.GO111MODULE = 'on';
-  }
-
-  function go(...args) {
-    debug('Exec %o', `go ${args.join(' ')}`);
-    return execa('go', args, { stdio: 'inherit', ...opts, env });
-  }
-  go.cwd = opts.cwd || process.cwd();
-  go.get = get;
-  go.build = build;
-  go.goPath = goPath;
-  await createGoPathTree(goPath, platform, arch);
-  return go;
-}
-
-async function downloadGo(
-  dir = GO_DIR,
-  version = '1.12',
-  platform = process.platform,
-  arch = process.arch,
-) {
-  debug('Installing `go` v%s to %o for %s %s', version, dir, platform, arch);
-
-  const url = getGoUrl(version, platform, arch);
-  debug('Downloading `go` URL: %o', url);
-  const res = await fetch(url);
-
-  if (!res.ok) {
-    throw new Error(`Failed to download: ${url} (${res.status})`);
-  }
-
-  // TODO: use a zip extractor when `ext === "zip"`
-  await mkdirp(dir);
-  await new Promise((resolve, reject) => {
-    res.body
-      .on('error', reject)
-      .pipe(tar.extract({ cwd: dir, strip: 1 }))
-      .on('error', reject)
-      .on('finish', resolve);
-  });
-
-  return createGo(dir, platform, arch);
-}
-
-module.exports = {
-  createGo,
-  downloadGo,
-  getExportedFunctionName,
-};

packages/now-go/go-helpers.ts

@@ -0,0 +1,170 @@
+import tar from 'tar';
+import execa from 'execa';
+import fetch from 'node-fetch';
+import { mkdirp, pathExists } from 'fs-extra';
+import { dirname, join } from 'path';
+import { homedir } from 'os';
+import Debug from 'debug';
+
+const debug = Debug('@now/go:go-helpers');
+const archMap = new Map([['x64', 'amd64'], ['x86', '386']]);
+const platformMap = new Map([['win32', 'windows']]);
+
+// Location where the `go` binary will be installed after `postinstall`
+const GO_DIR = join(__dirname, 'go');
+const GO_BIN = join(GO_DIR, 'bin/go');
+
+const getPlatform = (p: string) => platformMap.get(p) || p;
+const getArch = (a: string) => archMap.get(a) || a;
+const getGoUrl = (version: string, platform: string, arch: string) => {
+  const goArch = getArch(arch);
+  const goPlatform = getPlatform(platform);
+  const ext = platform === 'win32' ? 'zip' : 'tar.gz';
+  return `https://dl.google.com/go/go${version}.${goPlatform}-${goArch}.${ext}`;
+};
+
+export async function getAnalyzedEntrypoint(filePath: string, modulePath = '') {
+  debug('Analyzing entrypoint %o', filePath);
+  const bin = join(__dirname, 'analyze');
+
+  const isAnalyzeExist = await pathExists(bin);
+  if (!isAnalyzeExist) {
+    const src = join(__dirname, 'util', 'analyze.go');
+    const dest = join(__dirname, 'analyze');
+    const go = await downloadGo();
+    await go.build(src, dest);
+  }
+
+  const args = [`-modpath=${modulePath}`, filePath];
+
+  const analyzed = await execa.stdout(bin, args);
+  debug('Analyzed entrypoint %o', analyzed);
+  return analyzed;
+}
+
+// Creates a `$GOPATH` directory tree, as per `go help gopath` instructions.
+// Without this, `go` won't recognize the `$GOPATH`.
+function createGoPathTree(goPath: string, platform: string, arch: string) {
+  const tuple = `${getPlatform(platform)}_${getArch(arch)}`;
+  debug('Creating GOPATH directory structure for %o (%s)', goPath, tuple);
+  return Promise.all([
+    mkdirp(join(goPath, 'bin')),
+    mkdirp(join(goPath, 'pkg', tuple)),
+  ]);
+}
+
+class GoWrapper {
+  private env: { [key: string]: string };
+  private opts: execa.Options;
+
+  constructor(env: { [key: string]: string }, opts: execa.Options = {}) {
+    if (!opts.cwd) {
+      opts.cwd = process.cwd();
+    }
+    this.env = env;
+    this.opts = opts;
+  }
+
+  private execute(...args: string[]) {
+    const { opts, env } = this;
+    debug('Exec %o', `go ${args.join(' ')}`);
+    return execa('go', args, { stdio: 'inherit', ...opts, env });
+  }
+
+  mod() {
+    return this.execute('mod', 'tidy');
+  }
+
+  get(src?: string) {
+    const args = ['get'];
+    if (src) {
+      debug('Fetching `go` dependencies for file %o', src);
+      args.push(src);
+    } else {
+      debug('Fetching `go` dependencies for cwd %o', this.opts.cwd);
+    }
+    return this.execute(...args);
+  }
+
+  build(src: string | string[], dest: string, ldsflags = '-s -w') {
+    debug('Building optimized `go` binary %o -> %o', src, dest);
+    const sources = Array.isArray(src) ? src : [src];
+    return this.execute('build', '-ldflags', ldsflags, '-o', dest, ...sources);
+  }
+}
+
+export async function createGo(
+  goPath: string,
+  platform = process.platform,
+  arch = process.arch,
+  opts: execa.Options = {},
+  goMod = false
+) {
+  const path = `${dirname(GO_BIN)}:${process.env.PATH}`;
+  const env: { [key: string]: string } = {
+    ...process.env,
+    PATH: path,
+    GOPATH: goPath,
+    ...opts.env,
+  };
+  if (goMod) {
+    env.GO111MODULE = 'on';
+  }
+  await createGoPathTree(goPath, platform, arch);
+  return new GoWrapper(env, opts);
+}
+
+export async function downloadGo(
+  dir = GO_DIR,
+  version = '1.12',
+  platform = process.platform,
+  arch = process.arch
+) {
+  // Check default `Go` in user machine
+  const isUserGo = await pathExists(join(homedir(), 'go'));
+
+  // If we found GOPATH in ENV, or default `Go` path exists
+  // asssume that user have `Go` installed
+  if (isUserGo || process.env.GOPATH !== undefined) {
+    const { stdout } = await execa('go', ['version']);
+
+    if (parseInt(stdout.split('.')[1]) >= 11) {
+      return createGo(dir, platform, arch);
+    }
+
+    throw new Error(
+      `Your current ${stdout} doesn't support Go Modules. Please update.`
+    );
+  } else {
+    // Check `Go` bin in builder CWD
+    const isGoExist = await pathExists(join(dir, 'bin'));
+    if (!isGoExist) {
+      debug(
+        'Installing `go` v%s to %o for %s %s',
+        version,
+        dir,
+        platform,
+        arch
+      );
+      const url = getGoUrl(version, platform, arch);
+      debug('Downloading `go` URL: %o', url);
+      console.log('Downloading Go ...');
+      const res = await fetch(url);
+
+      if (!res.ok) {
+        throw new Error(`Failed to download: ${url} (${res.status})`);
+      }
+
+      // TODO: use a zip extractor when `ext === "zip"`
+      await mkdirp(dir);
+      await new Promise((resolve, reject) => {
+        res.body
+          .on('error', reject)
+          .pipe(tar.extract({ cwd: dir, strip: 1 }))
+          .on('error', reject)
+          .on('finish', resolve);
+      });
+    }
+    return createGo(dir, platform, arch);
+  }
+}

packages/now-go/index.js

@@ -1,210 +0,0 @@
-const { join, sep, dirname } = require('path');
-const {
-  readFile, writeFile, pathExists, move,
-} = require('fs-extra');
-
-const glob = require('@now/build-utils/fs/glob.js'); // eslint-disable-line import/no-extraneous-dependencies
-const download = require('@now/build-utils/fs/download.js'); // eslint-disable-line import/no-extraneous-dependencies
-const { createLambda } = require('@now/build-utils/lambda.js'); // eslint-disable-line import/no-extraneous-dependencies
-const getWritableDirectory = require('@now/build-utils/fs/get-writable-directory.js'); // eslint-disable-line import/no-extraneous-dependencies
-const { createGo, getExportedFunctionName } = require('./go-helpers');
-
-const config = {
-  maxLambdaSize: '10mb',
-};
-
-async function build({ files, entrypoint }) {
-  console.log('Downloading user files...');
-
-  const [goPath, outDir] = await Promise.all([
-    getWritableDirectory(),
-    getWritableDirectory(),
-  ]);
-
-  const srcPath = join(goPath, 'src', 'lambda');
-  const downloadedFiles = await download(files, srcPath);
-
-  console.log(`Parsing AST for "${entrypoint}"`);
-  let parseFunctionName;
-  try {
-    parseFunctionName = await getExportedFunctionName(
-      downloadedFiles[entrypoint].fsPath,
-    );
-  } catch (err) {
-    console.log(`Failed to parse AST for "${entrypoint}"`);
-    throw err;
-  }
-
-  if (!parseFunctionName) {
-    const err = new Error(
-      `Could not find an exported function in "${entrypoint}"`,
-    );
-    console.log(err.message);
-    throw err;
-  }
-
-  const handlerFunctionName = parseFunctionName.split(',')[0];
-
-  console.log(
-    `Found exported function "${handlerFunctionName}" in "${entrypoint}"`,
-  );
-
-  // we need `main.go` in the same dir as the entrypoint,
-  // otherwise `go build` will refuse to build
-  const entrypointDirname = dirname(downloadedFiles[entrypoint].fsPath);
-
-  // check if package name other than main
-  const packageName = parseFunctionName.split(',')[1];
-  const isGoModExist = await pathExists(join(entrypointDirname, 'go.mod'));
-  if (packageName !== 'main') {
-    const go = await createGo(
-      goPath,
-      process.platform,
-      process.arch,
-      {
-        cwd: entrypointDirname,
-      },
-      true,
-    );
-    if (!isGoModExist) {
-      try {
-        const defaultGoModContent = `module ${packageName}`;
-
-        await writeFile(join(entrypointDirname, 'go.mod'), defaultGoModContent);
-      } catch (err) {
-        console.log(`failed to create default go.mod for ${packageName}`);
-        throw err;
-      }
-    }
-
-    const mainModGoFileName = 'main__mod__.go';
-    const modMainGoContents = await readFile(
-      join(__dirname, mainModGoFileName),
-      'utf8',
-    );
-
-    let goPackageName = `${packageName}/${packageName}`;
-    const goFuncName = `${packageName}.${handlerFunctionName}`;
-
-    if (isGoModExist) {
-      const goModContents = await readFile(
-        join(entrypointDirname, 'go.mod'),
-        'utf8',
-      );
-      goPackageName = `${
-        goModContents.split('\n')[0].split(' ')[1]
-      }/${packageName}`;
-    }
-
-    const mainModGoContents = modMainGoContents
-      .replace('__NOW_HANDLER_PACKAGE_NAME', goPackageName)
-      .replace('__NOW_HANDLER_FUNC_NAME', goFuncName);
-
-    // write main__mod__.go
-    await writeFile(
-      join(entrypointDirname, mainModGoFileName),
-      mainModGoContents,
-    );
-
-    // move user go file to folder
-    try {
-      // default path
-      let finalDestination = join(entrypointDirname, packageName, entrypoint);
-      const entrypointArr = entrypoint.split(sep);
-
-      // if `entrypoint` include folder, only use filename
-      if (entrypointArr.length > 1) {
-        finalDestination = join(
-          entrypointDirname,
-          packageName,
-          entrypointArr.pop(),
-        );
-      }
-
-      await move(downloadedFiles[entrypoint].fsPath, finalDestination);
-    } catch (err) {
-      console.log('failed to move entry to package folder');
-      throw err;
-    }
-
-    console.log('tidy go.mod file');
-    try {
-      // ensure go.mod up-to-date
-      await go('mod', 'tidy');
-    } catch (err) {
-      console.log('failed to `go mod tidy`');
-      throw err;
-    }
-
-    console.log('Running `go build`...');
-    const destPath = join(outDir, 'handler');
-    try {
-      const src = [join(entrypointDirname, mainModGoFileName)];
-      await go.build({ src, dest: destPath });
-    } catch (err) {
-      console.log('failed to `go build`');
-      throw err;
-    }
-  } else {
-    const go = await createGo(
-      goPath,
-      process.platform,
-      process.arch,
-      {
-        cwd: entrypointDirname,
-      },
-      false,
-    );
-    const origianlMainGoContents = await readFile(
-      join(__dirname, 'main.go'),
-      'utf8',
-    );
-    const mainGoContents = origianlMainGoContents.replace(
-      '__NOW_HANDLER_FUNC_NAME',
-      handlerFunctionName,
-    );
-
-    // in order to allow the user to have `main.go`,
-    // we need our `main.go` to be called something else
-    const mainGoFileName = 'main__now__go__.go';
-
-    // Go doesn't like to build files in different directories,
-    // so now we place `main.go` together with the user code
-    await writeFile(join(entrypointDirname, mainGoFileName), mainGoContents);
-
-    // `go get` will look at `*.go` (note we set `cwd`), parse the `import`s
-    // and download any packages that aren't part of the stdlib
-    try {
-      await go.get();
-    } catch (err) {
-      console.log('failed to `go get`');
-      throw err;
-    }
-
-    console.log('Running `go build`...');
-    const destPath = join(outDir, 'handler');
-    try {
-      const src = [
-        join(entrypointDirname, mainGoFileName),
-        downloadedFiles[entrypoint].fsPath,
-      ];
-      await go.build({ src, dest: destPath });
-    } catch (err) {
-      console.log('failed to `go build`');
-      throw err;
-    }
-  }
-
-  const lambda = await createLambda({
-    files: await glob('**', outDir),
-    handler: 'handler',
-    runtime: 'go1.x',
-    environment: {},
-  });
-
-  return {
-    [entrypoint]: lambda,
-  };
-}
-
-module.exports = { config, build };

packages/now-go/index.ts

@@ -0,0 +1,427 @@
+import { join, sep, dirname, basename } from 'path';
+import { readFile, writeFile, pathExists, move } from 'fs-extra';
+import { homedir } from 'os';
+import execa from 'execa';
+
+import {
+  glob,
+  download,
+  createLambda,
+  getWriteableDirectory,
+  BuildOptions,
+  shouldServe,
+  Files,
+} from '@now/build-utils';
+
+import { createGo, getAnalyzedEntrypoint } from './go-helpers';
+
+interface Analyzed {
+  found?: boolean;
+  packageName: string;
+  functionName: string;
+  watch: string[];
+}
+interface BuildParamsMeta {
+  isDev: boolean | undefined;
+}
+interface BuildParamsType extends BuildOptions {
+  files: Files;
+  entrypoint: string;
+  workPath: string;
+  meta: BuildParamsMeta;
+}
+
+// Initialize private git repo for Go Modules
+async function initPrivateGit(credentials: string) {
+  await execa('git', [
+    'config',
+    '--global',
+    'credential.helper',
+    `store --file ${join(homedir(), '.git-credentials')}`,
+  ]);
+
+  await writeFile(join(homedir(), '.git-credentials'), credentials);
+}
+
+export const version = 2;
+
+export async function build({
+  files,
+  entrypoint,
+  config,
+  workPath,
+  meta = {} as BuildParamsMeta,
+}: BuildParamsType) {
+  if (process.env.GIT_CREDENTIALS && !meta.isDev) {
+    console.log('Initialize Git credentials...');
+    await initPrivateGit(process.env.GIT_CREDENTIALS);
+  }
+
+  if (process.env.GO111MODULE) {
+    console.log(`\nManually assigning 'GO111MODULE' is not recommended.
+
+By default:
+  - 'GO111MODULE=on' If entrypoint package name is not 'main'
+  - 'GO111MODULE=off' If entrypoint package name is 'main'
+
+We highly recommend you leverage Go Modules in your project.
+Learn more: https://github.com/golang/go/wiki/Modules
+`);
+  }
+
+  console.log('Downloading user files...');
+  const entrypointArr = entrypoint.split(sep);
+
+  let [goPath, outDir] = await Promise.all([
+    getWriteableDirectory(),
+    getWriteableDirectory(),
+  ]);
+
+  const srcPath = join(goPath, 'src', 'lambda');
+  let downloadedFiles;
+  if (meta.isDev) {
+    downloadedFiles = await download(files, workPath, meta);
+  } else {
+    downloadedFiles = await download(files, srcPath);
+  }
+
+  console.log(`Parsing AST for "${entrypoint}"`);
+  let analyzed: string;
+  try {
+    let goModAbsPathDir = '';
+    for (const file of Object.keys(downloadedFiles)) {
+      if (file === 'go.mod') {
+        goModAbsPathDir = dirname(downloadedFiles[file].fsPath);
+      }
+    }
+    analyzed = await getAnalyzedEntrypoint(
+      downloadedFiles[entrypoint].fsPath,
+      goModAbsPathDir
+    );
+  } catch (err) {
+    console.log(`Failed to parse AST for "${entrypoint}"`);
+    throw err;
+  }
+
+  if (!analyzed) {
+    const err = new Error(
+      `Could not find an exported function in "${entrypoint}"
+Learn more: https://zeit.co/docs/v2/deployments/official-builders/go-now-go/#entrypoint
+      `
+    );
+    console.log(err.message);
+    throw err;
+  }
+
+  const parsedAnalyzed = JSON.parse(analyzed) as Analyzed;
+
+  if (meta.isDev) {
+    let base = null;
+
+    if (config && config.zeroConfig) {
+      base = workPath;
+    } else {
+      base = dirname(downloadedFiles['now.json'].fsPath);
+    }
+
+    const destNow = join(
+      base,
+      '.now',
+      'cache',
+      basename(entrypoint, '.go'),
+      'src',
+      'lambda'
+    );
+    // this will ensure Go rebuilt fast
+    goPath = join(base, '.now', 'cache', basename(entrypoint, '.go'));
+    await download(downloadedFiles, destNow);
+
+    downloadedFiles = await glob('**', destNow);
+  }
+
+  // find `go.mod` in downloadedFiles
+  const entrypointDirname = dirname(downloadedFiles[entrypoint].fsPath);
+  let isGoModExist = false;
+  let goModPath = '';
+  let isGoModInRootDir = false;
+  for (const file of Object.keys(downloadedFiles)) {
+    const fileDirname = dirname(downloadedFiles[file].fsPath);
+    if (file === 'go.mod') {
+      isGoModExist = true;
+      isGoModInRootDir = true;
+      goModPath = fileDirname;
+    } else if (file.endsWith('go.mod') && !file.endsWith('vendor')) {
+      if (entrypointDirname === fileDirname) {
+        isGoModExist = true;
+        goModPath = fileDirname;
+        break;
+      }
+    }
+  }
+
+  const input = entrypointDirname;
+  var includedFiles: Files = {};
+
+  if (config && config.includeFiles) {
+    for (const pattern of config.includeFiles) {
+      const files = await glob(pattern, input);
+      for (const assetName of Object.keys(files)) {
+        includedFiles[assetName] = files[assetName];
+      }
+    }
+  }
+
+  const handlerFunctionName = parsedAnalyzed.functionName;
+  console.log(
+    `Found exported function "${handlerFunctionName}" in "${entrypoint}"`
+  );
+
+  if (!isGoModExist && 'vendor' in downloadedFiles) {
+    throw new Error('`go.mod` is required to use a `vendor` directory.');
+  }
+
+  // check if package name other than main
+  // using `go.mod` way building the handler
+  const packageName = parsedAnalyzed.packageName;
+
+  if (isGoModExist && packageName === 'main') {
+    throw new Error('Please change `package main` to `package handler`');
+  }
+
+  if (packageName !== 'main') {
+    const go = await createGo(
+      goPath,
+      process.platform,
+      process.arch,
+      {
+        cwd: entrypointDirname,
+      },
+      true
+    );
+    if (!isGoModExist) {
+      try {
+        const defaultGoModContent = `module ${packageName}`;
+
+        await writeFile(join(entrypointDirname, 'go.mod'), defaultGoModContent);
+      } catch (err) {
+        console.log(`failed to create default go.mod for ${packageName}`);
+        throw err;
+      }
+    }
+
+    const mainModGoFileName = 'main__mod__.go';
+    const modMainGoContents = await readFile(
+      join(__dirname, mainModGoFileName),
+      'utf8'
+    );
+
+    let goPackageName = `${packageName}/${packageName}`;
+    const goFuncName = `${packageName}.${handlerFunctionName}`;
+
+    if (isGoModExist) {
+      const goModContents = await readFile(join(goModPath, 'go.mod'), 'utf8');
+      const usrModName = goModContents.split('\n')[0].split(' ')[1];
+
+      if (entrypointArr.length > 1 && isGoModInRootDir) {
+        let cleanPackagePath = [...entrypointArr];
+        cleanPackagePath.pop();
+        goPackageName = `${usrModName}/${cleanPackagePath.join('/')}`;
+      } else {
+        goPackageName = `${usrModName}/${packageName}`;
+      }
+    }
+
+    const mainModGoContents = modMainGoContents
+      .replace('__NOW_HANDLER_PACKAGE_NAME', goPackageName)
+      .replace('__NOW_HANDLER_FUNC_NAME', goFuncName);
+
+    if (meta.isDev && isGoModExist && isGoModInRootDir) {
+      await writeFile(
+        join(dirname(downloadedFiles['go.mod'].fsPath), mainModGoFileName),
+        mainModGoContents
+      );
+    } else if (isGoModExist && isGoModInRootDir) {
+      await writeFile(join(srcPath, mainModGoFileName), mainModGoContents);
+    } else if (isGoModExist && !isGoModInRootDir) {
+      // using `go.mod` path to write main__mod__.go
+      await writeFile(join(goModPath, mainModGoFileName), mainModGoContents);
+    } else {
+      // using `entrypointDirname` to write main__mod__.go
+      await writeFile(
+        join(entrypointDirname, mainModGoFileName),
+        mainModGoContents
+      );
+    }
+
+    // move user go file to folder
+    try {
+      // default path
+      let finalDestination = join(entrypointDirname, packageName, entrypoint);
+      let forceMove = false;
+
+      if (meta.isDev) {
+        forceMove = true;
+      }
+
+      // if `entrypoint` include folder, only use filename
+      if (entrypointArr.length > 1) {
+        finalDestination = join(
+          entrypointDirname,
+          packageName,
+          entrypointArr[entrypointArr.length - 1]
+        );
+      }
+
+      if (
+        dirname(downloadedFiles[entrypoint].fsPath) === goModPath ||
+        !isGoModExist
+      ) {
+        await move(downloadedFiles[entrypoint].fsPath, finalDestination, {
+          overwrite: forceMove,
+        });
+      }
+    } catch (err) {
+      console.log('failed to move entry to package folder');
+      throw err;
+    }
+
+    let baseGoModPath = '';
+    if (meta.isDev && isGoModExist && isGoModInRootDir) {
+      baseGoModPath = dirname(downloadedFiles['go.mod'].fsPath);
+    } else if (isGoModExist && isGoModInRootDir) {
+      baseGoModPath = srcPath;
+    } else if (isGoModExist && !isGoModInRootDir) {
+      baseGoModPath = goModPath;
+    } else {
+      baseGoModPath = entrypointDirname;
+    }
+
+    if (meta.isDev) {
+      const isGoModBk = await pathExists(join(baseGoModPath, 'go.mod.bk'));
+      if (isGoModBk) {
+        await move(
+          join(baseGoModPath, 'go.mod.bk'),
+          join(baseGoModPath, 'go.mod'),
+          { overwrite: true }
+        );
+        await move(
+          join(baseGoModPath, 'go.sum.bk'),
+          join(baseGoModPath, 'go.sum'),
+          { overwrite: true }
+        );
+      }
+    }
+
+    console.log('Tidy `go.mod` file...');
+    try {
+      // ensure go.mod up-to-date
+      await go.mod();
+    } catch (err) {
+      console.log('failed to `go mod tidy`');
+      throw err;
+    }
+
+    console.log('Running `go build`...');
+    const destPath = join(outDir, 'handler');
+
+    try {
+      let src = [join(baseGoModPath, mainModGoFileName)];
+
+      await go.build(src, destPath, config.ldsflags);
+    } catch (err) {
+      console.log('failed to `go build`');
+      throw err;
+    }
+    if (meta.isDev) {
+      // caching for `now dev`
+      await move(
+        join(baseGoModPath, 'go.mod'),
+        join(baseGoModPath, 'go.mod.bk'),
+        { overwrite: true }
+      );
+      await move(
+        join(baseGoModPath, 'go.sum'),
+        join(baseGoModPath, 'go.sum.bk'),
+        { overwrite: true }
+      );
+    }
+  } else {
+    // legacy mode
+    // we need `main.go` in the same dir as the entrypoint,
+    // otherwise `go build` will refuse to build
+    const go = await createGo(
+      goPath,
+      process.platform,
+      process.arch,
+      {
+        cwd: entrypointDirname,
+      },
+      false
+    );
+    const origianlMainGoContents = await readFile(
+      join(__dirname, 'main.go'),
+      'utf8'
+    );
+    const mainGoContents = origianlMainGoContents.replace(
+      '__NOW_HANDLER_FUNC_NAME',
+      handlerFunctionName
+    );
+
+    // in order to allow the user to have `main.go`,
+    // we need our `main.go` to be called something else
+    const mainGoFileName = 'main__now__go__.go';
+
+    // Go doesn't like to build files in different directories,
+    // so now we place `main.go` together with the user code
+    await writeFile(join(entrypointDirname, mainGoFileName), mainGoContents);
+
+    // `go get` will look at `*.go` (note we set `cwd`), parse the `import`s
+    // and download any packages that aren't part of the stdlib
+    console.log('Running `go get`...');
+    try {
+      await go.get();
+    } catch (err) {
+      console.log('failed to `go get`');
+      throw err;
+    }
+
+    console.log('Running `go build`...');
+    const destPath = join(outDir, 'handler');
+    try {
+      const src = [
+        join(entrypointDirname, mainGoFileName),
+        downloadedFiles[entrypoint].fsPath,
+      ];
+      await go.build(src, destPath);
+    } catch (err) {
+      console.log('failed to `go build`');
+      throw err;
+    }
+  }
+
+  const lambda = await createLambda({
+    files: { ...(await glob('**', outDir)), ...includedFiles },
+    handler: 'handler',
+    runtime: 'go1.x',
+    environment: {},
+  });
+  const output = {
+    [entrypoint]: lambda,
+  };
+
+  let watch = parsedAnalyzed.watch;
+  let watchSub: string[] = [];
+  // if `entrypoint` located in subdirectory
+  // we will need to concat it with return watch array
+  if (entrypointArr.length > 1) {
+    entrypointArr.pop();
+    watchSub = parsedAnalyzed.watch.map(file => join(...entrypointArr, file));
+  }
+
+  return {
+    output,
+    watch: watch.concat(watchSub),
+  };
+}
+
+export { shouldServe };

packages/now-go/install.ts

@@ -0,0 +1,6 @@
+import { downloadGo } from './go-helpers';
+
+downloadGo().catch(err => {
+  console.error(err);
+  process.exit(1);
+});

packages/now-go/package.json

@@ -1,27 +1,34 @@
 {
   "name": "@now/go",
-  "version": "0.4.0",
+  "version": "0.5.8",
   "license": "MIT",
+  "main": "./dist/index",
+  "homepage": "https://zeit.co/docs/v2/deployments/official-builders/go-now-go",
   "repository": {
     "type": "git",
     "url": "https://github.com/zeit/now-builders.git",
     "directory": "packages/now-go"
   },
   "scripts": {
-    "postinstall": "node ./util/install"
+    "build": "./build.sh",
+    "test": "./build.sh && jest",
+    "prepublish": "./build.sh",
+    "now-postinstall": "node dist/install/index.js"
   },
   "files": [
-    "*.js",
+    "dist"
-    "main.go",
-    "main__mod__.go",
-    "util"
   ],
-  "dependencies": {
+  "devDependencies": {
+    "@types/debug": "^4.1.3",
+    "@types/execa": "^0.9.0",
+    "@types/fs-extra": "^5.0.5",
+    "@types/node-fetch": "^2.3.0",
+    "@types/tar": "^4.0.0",
     "debug": "^4.1.1",
     "execa": "^1.0.0",
     "fs-extra": "^7.0.0",
-    "mkdirp-promise": "5.0.1",
     "node-fetch": "^2.2.1",
-    "tar": "4.4.6"
+    "tar": "4.4.6",
+    "typescript": "3.5.2"
   }
 }

packages/now-go/test/fixtures/01-cowsay/now.json

@@ -8,4 +8,4 @@
     { "path": "/", "mustContain": "cow:RANDOMNESS_PLACEHOLDER" },
     { "path": "/subdirectory", "mustContain": "subcow:RANDOMNESS_PLACEHOLDER" }
   ]
-}
+}

packages/now-go/test/fixtures/03-env-vars/build-env/go.mod

@@ -0,0 +1 @@
+module build-env

packages/now-go/test/fixtures/03-env-vars/build-env/index.go

@@ -0,0 +1,17 @@
+package buildenv
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+)
+
+// Handler function
+func Handler(w http.ResponseWriter, r *http.Request) {
+	rdm := os.Getenv("RANDOMNESS_BUILD_ENV")
+	if rdm == "" {
+		fmt.Println("No build env received")
+	}
+
+	fmt.Fprintf(w, rdm+":build-env")
+}

packages/now-go/test/fixtures/03-env-vars/env/go.mod

@@ -0,0 +1 @@
+module env

packages/now-go/test/fixtures/03-env-vars/env/index.go

@@ -0,0 +1,17 @@
+package env
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+)
+
+// Handler function
+func Handler(w http.ResponseWriter, r *http.Request) {
+	rdm := os.Getenv("RANDOMNESS_ENV")
+	if rdm == "" {
+		fmt.Println("No env received")
+	}
+
+	fmt.Fprintf(w, rdm)
+}

packages/now-go/test/fixtures/03-env-vars/now.json

@@ -0,0 +1,18 @@
+{
+  "version": 2,
+  "builds": [
+    {
+      "src": "env/index.go",
+      "use": "@now/go"
+    }
+  ],
+  "env": {
+    "RANDOMNESS_ENV": "RANDOMNESS_PLACEHOLDER"
+  },
+  "probes": [
+    {
+      "path": "/env",
+      "mustContain": "RANDOMNESS_PLACEHOLDER"
+    }
+  ]
+}

packages/now-go/test/fixtures/06-content-type/index.go

@@ -0,0 +1,11 @@
+package function
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// Handler function
+func Handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "RANDOMNESS_PLACEHOLDER")
+}

packages/now-go/test/fixtures/06-content-type/now.json

@@ -0,0 +1,4 @@
+{
+  "version": 2,
+  "builds": [{ "src": "index.go", "use": "@now/go" }]
+}

packages/now-go/test/fixtures/07-content-length/now.json

@@ -0,0 +1,7 @@
+{
+  "version": 2,
+  "builds": [{ "src": "*.go", "use": "@now/go" }],
+  "env": {
+    "RANDOMNESS_ENV_VAR": "RANDOMNESS_PLACEHOLDER"
+  }
+}

packages/now-go/test/fixtures/07-content-length/test1.go

@@ -0,0 +1,16 @@
+package function
+
+import (
+	"net/http"
+	"os"
+	"strconv"
+)
+
+// HandlerTest1 function
+func HandlerTest1(w http.ResponseWriter, r *http.Request) {
+	rdm := os.Getenv("RANDOMNESS_ENV_VAR")
+
+	w.WriteHeader(401)
+	w.Header().Set("content-length", strconv.Itoa(len(rdm+":content-length")))
+	w.Write([]byte(rdm + ":content-length"))
+}

packages/now-go/test/fixtures/07-content-length/test2.go

@@ -0,0 +1,12 @@
+package function
+
+import (
+	"net/http"
+)
+
+// HandlerTest2 function
+func HandlerTest2(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Length", "2")
+	w.WriteHeader(401)
+	w.Write([]byte(""))
+}

packages/now-go/test/fixtures/07-content-length/test3.go

@@ -0,0 +1,13 @@
+package function
+
+import (
+	"net/http"
+	"os"
+)
+
+// HandlerTest3 function
+func HandlerTest3(w http.ResponseWriter, r *http.Request) {
+	rev := os.Getenv("RANDOMNESS_ENV_VAR")
+	w.WriteHeader(401)
+	w.Write([]byte(rev + ":content-length"))
+}

packages/now-go/test/fixtures/08-include-files/index.go

@@ -0,0 +1,16 @@
+package cowsay
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+)
+
+// Handler function
+func Handler(w http.ResponseWriter, r *http.Request) {
+	bts, err := ioutil.ReadFile("templates/foo.txt")
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+	}
+	fmt.Fprintf(w, string(bts))
+}

packages/now-go/test/fixtures/08-include-files/now.json

@@ -0,0 +1,18 @@
+{
+  "version": 2,
+  "builds": [
+    {
+      "src": "index.go",
+      "use": "@now/go",
+      "config": {
+        "includeFiles": ["templates/**"]
+      }
+    }
+  ],
+  "probes": [
+    {
+      "path": "/",
+      "mustContain": "foobar from file"
+    }
+  ]
+}

packages/now-go/test/fixtures/08-include-files/templates/foo.txt

@@ -0,0 +1 @@
+foobar from file

packages/now-go/test/fixtures/09-exported-function/index.go

@@ -0,0 +1,22 @@
+package function
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// Person struct
+type Person struct {
+	name string
+	age  int
+}
+
+// NewPerson struct method
+func NewPerson(name string, age int) *Person {
+	return &Person{name: name, age: age}
+}
+
+// H func
+func H(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "RANDOMNESS_PLACEHOLDER")
+}

packages/now-go/test/fixtures/09-exported-function/now.json

@@ -0,0 +1,5 @@
+{
+  "version": 2,
+  "builds": [{ "src": "index.go", "use": "@now/go" }],
+  "probes": [{ "path": "/", "mustContain": "RANDOMNESS_PLACEHOLDER" }]
+}

packages/now-go/test/fixtures/10-go-mod/go.mod

@@ -0,0 +1,3 @@
+module go-mod
+
+go 1.12

packages/now-go/test/fixtures/10-go-mod/index.go

@@ -0,0 +1,11 @@
+package handler
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// Handler func
+func Handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "RANDOMNESS_PLACEHOLDER")
+}

packages/now-go/test/fixtures/10-go-mod/now.json

@@ -0,0 +1,5 @@
+{
+  "version": 2,
+  "builds": [{ "src": "index.go", "use": "@now/go" }],
+  "probes": [{ "path": "/", "mustContain": "RANDOMNESS_PLACEHOLDER" }]
+}

packages/now-go/test/fixtures/11-go-mod-shared/api/index.go

@@ -0,0 +1,12 @@
+package api
+
+import (
+	"fmt"
+	"net/http"
+	"with-shared/shared"
+)
+
+// Handler func
+func Handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, shared.Say("RANDOMNESS_PLACEHOLDER"))
+}

packages/now-go/test/fixtures/11-go-mod-shared/go.mod

@@ -0,0 +1,3 @@
+module with-shared
+
+go 1.12

packages/now-go/test/fixtures/11-go-mod-shared/now.json

@@ -0,0 +1,5 @@
+{
+  "version": 2,
+  "builds": [{ "src": "api/*.go", "use": "@now/go" }],
+  "probes": [{ "path": "/api", "mustContain": "RANDOMNESS_PLACEHOLDER" }]
+}

packages/now-go/test/fixtures/11-go-mod-shared/shared/shared.go

@@ -0,0 +1,6 @@
+package shared
+
+// Say func
+func Say(text string) string {
+	return text
+}

packages/now-go/test/fixtures/12-go-mod-subs/now.json

@@ -0,0 +1,8 @@
+{
+  "version": 2,
+  "builds": [{ "src": "**/*.go", "use": "@now/go" }],
+  "probes": [
+    { "path": "/sub-1", "mustContain": "RANDOMNESS_PLACEHOLDER" },
+    { "path": "/sub-2", "mustContain": "RANDOMNESS_PLACEHOLDER" }
+  ]
+}

packages/now-go/test/fixtures/12-go-mod-subs/sub-1/go.mod

@@ -0,0 +1,3 @@
+module sub-1
+
+go 1.12

packages/now-go/test/fixtures/12-go-mod-subs/sub-1/index.go

@@ -0,0 +1,11 @@
+package sub1
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// Handler func
+func Handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "RANDOMNESS_PLACEHOLDER")
+}

packages/now-go/test/fixtures/12-go-mod-subs/sub-2/go.mod

@@ -0,0 +1,3 @@
+module sub-2
+
+go 1.12

packages/now-go/test/fixtures/12-go-mod-subs/sub-2/index.go

@@ -0,0 +1,11 @@
+package sub2
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// Handler func
+func Handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "RANDOMNESS_PLACEHOLDER")
+}

packages/now-go/test/fixtures/13-go-mod-nested/api/nested/index.go

@@ -0,0 +1,12 @@
+package nested
+
+import (
+	"fmt"
+	"net/http"
+	"with-nested/shared"
+)
+
+// Handler func
+func Handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, shared.Say("lol:RANDOMNESS_PLACEHOLDER"))
+}

packages/now-go/test/fixtures/13-go-mod-nested/go.mod

@@ -0,0 +1,3 @@
+module with-nested
+
+go 1.12

packages/now-go/test/fixtures/13-go-mod-nested/now.json

@@ -0,0 +1,5 @@
+{
+  "version": 2,
+  "builds": [{ "src": "api/nested/*.go", "use": "@now/go" }],
+  "probes": [{ "path": "/api/nested", "mustContain": "RANDOMNESS_PLACEHOLDER" }]
+}

packages/now-go/test/fixtures/13-go-mod-nested/shared/shared.go

@@ -0,0 +1,6 @@
+package shared
+
+// Say func
+func Say(text string) string {
+	return text
+}

packages/now-go/test/fixtures/14-go-mod-sub/api/index.go

@@ -0,0 +1,11 @@
+package handler
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// Handler func
+func Handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "hello:RANDOMNESS_PLACEHOLDER")
+}

packages/now-go/test/fixtures/14-go-mod-sub/now.json

@@ -0,0 +1,5 @@
+{
+  "version": 2,
+  "builds": [{ "src": "api/**/*.go", "use": "@now/go" }],
+  "probes": [{ "path": "/api", "mustContain": "RANDOMNESS_PLACEHOLDER" }]
+}