[next][node][static-build] Execute "vercel-build" script if defined (#4863)

* [build-utils] Make `runPackageJsonScript()` run the `vercel-` or `now-` if defined in `package.json`

* [build-utils] Export `getScriptName()`

* [next] Use `getScriptName()` and `remove()`

* [node] Update for `vercel-`

* [static-build] Update for `vercel-`

* Remove debug

* Add `getScriptName()` unit tests

* Test for `vercel-build` in e2e

* Make platform name behavior be opt-in

So that it's not a breaking behavior change.

* Check for only "vercel-build" or "now-build", but not "build"

* Simplify `getScriptName()` to return the first existing script in a possible set

* Revert change

* Fix test

Co-authored-by: Joe Haddad <joe.haddad@zeit.co>
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

packages/now-next/src/index.ts

@@ -7,6 +7,7 @@ const {
   getLambdaOptionsFromFunction,
   getNodeVersion,
   getSpawnOptions,
+  getScriptName,
   glob,
   runNpmInstall,
   runPackageJsonScript,
@@ -35,13 +36,7 @@ import {
 import { nodeFileTrace, NodeFileTraceReasons } from '@zeit/node-file-trace';
 import { ChildProcess, fork } from 'child_process';
 import escapeStringRegexp from 'escape-string-regexp';
-import {
-  lstat,
-  pathExists,
-  readFile,
-  unlink as unlinkFile,
-  writeFile,
-} from 'fs-extra';
+import { lstat, pathExists, readFile, remove, writeFile } from 'fs-extra';
 import os from 'os';
 import path from 'path';
 import resolveFrom from 'resolve-from';
@@ -108,13 +103,7 @@ const MAX_AGE_ONE_YEAR = 31536000;
 /**
  * Read package.json from files
  */
-async function readPackageJson(
-  entryPath: string
-): Promise<{
-  scripts?: { [key: string]: string };
-  dependencies?: { [key: string]: string };
-  devDependencies?: { [key: string]: string };
-}> {
+async function readPackageJson(entryPath: string): Promise<PackageJson> {
   const packagePath = path.join(entryPath, 'package.json');
 
   try {
@@ -329,49 +318,38 @@ export const build = async ({
   }
 
   const isLegacy = nextVersionRange && isLegacyNext(nextVersionRange);
-  let shouldRunScript = 'now-build';
-
   debug(`MODE: ${isLegacy ? 'legacy' : 'serverless'}`);
 
   if (isLegacy) {
-    try {
-      await unlinkFile(path.join(entryPath, 'yarn.lock'));
-    } catch (err) {
-      debug('no yarn.lock removed');
-    }
-
-    try {
-      await unlinkFile(path.join(entryPath, 'package-lock.json'));
-    } catch (err) {
-      debug('no package-lock.json removed');
-    }
-
     console.warn(
       "WARNING: your application is being deployed in @vercel/next's legacy mode. http://err.sh/vercel/vercel/now-next-legacy-mode"
     );
 
+    await Promise.all([
+      remove(path.join(entryPath, 'yarn.lock')),
+      remove(path.join(entryPath, 'package-lock.json')),
+    ]);
+
     debug('Normalizing package.json');
     const packageJson = normalizePackageJson(pkg);
     debug('Normalized package.json result: ', packageJson);
     await writePackageJson(entryPath, packageJson);
-  } else if (pkg.scripts && pkg.scripts['now-build']) {
-    debug('Found user `now-build` script');
-    shouldRunScript = 'now-build';
-  } else if (pkg.scripts && pkg.scripts['build']) {
-    debug('Found user `build` script');
-    shouldRunScript = 'build';
-  } else if (!pkg.scripts || !pkg.scripts['now-build']) {
-    debug(
+  }
+
+  const buildScriptName = getScriptName(pkg, [
+    'vercel-build',
+    'now-build',
+    'build',
+  ]);
+  let { buildCommand } = config;
+
+  if (!buildScriptName && !buildCommand) {
+    console.log(
       'Your application is being built using `next build`. ' +
-        'If you need to define a different build step, please create a `now-build` script in your `package.json` ' +
-        '(e.g. `{ "scripts": { "now-build": "npm run prepare && next build" } }`).'
+        'If you need to define a different build step, please create a `vercel-build` script in your `package.json` ' +
+        '(e.g. `{ "scripts": { "vercel-build": "npm run prepare && next build" } }`).'
     );
-    pkg.scripts = {
-      'now-build': 'next build',
-      ...(pkg.scripts || {}),
-    };
-    shouldRunScript = 'now-build';
-    await writePackageJson(entryPath, pkg);
+    buildCommand = 'next build';
   }
 
   if (process.env.NPM_AUTH_TOKEN) {
@@ -398,12 +376,11 @@ export const build = async ({
     await createServerlessConfig(workPath, entryPath, nextVersion);
   }
 
-  debug('Running user script...');
   const memoryToConsume = Math.floor(os.totalmem() / 1024 ** 2) - 128;
   const env: { [key: string]: string | undefined } = { ...spawnOpts.env };
   env.NODE_OPTIONS = `--max_old_space_size=${memoryToConsume}`;
 
-  if (config.buildCommand) {
+  if (buildCommand) {
     // Add `node_modules/.bin` to PATH
     const nodeBinPath = await getNodeBinPath({ cwd: entryPath });
     env.PATH = `${nodeBinPath}${path.delimiter}${env.PATH}`;
@@ -412,14 +389,14 @@ export const build = async ({
       `Added "${nodeBinPath}" to PATH env because a build command was used.`
     );
 
-    console.log(`Running "${config.buildCommand}"`);
-    await execCommand(config.buildCommand, {
+    console.log(`Running "${buildCommand}"`);
+    await execCommand(buildCommand, {
       ...spawnOpts,
       cwd: entryPath,
       env,
     });
-  } else {
-    await runPackageJsonScript(entryPath, shouldRunScript, {
+  } else if (buildScriptName) {
+    await runPackageJsonScript(entryPath, buildScriptName, {
       ...spawnOpts,
       env,
     });
@@ -667,7 +644,7 @@ export const build = async ({
   }
 
   if (process.env.NPM_AUTH_TOKEN) {
-    await unlinkFile(path.join(entryPath, '.npmrc'));
+    await remove(path.join(entryPath, '.npmrc'));
   }
 
   const pageLambdaRoutes: Route[] = [];

packages/now-next/test/fixtures/10-export-cache-headers/package.json

@@ -1,6 +1,6 @@
 {
   "scripts": {
-    "build": "next build && next export"
+    "now-build": "next build && next export"
   },
   "dependencies": {
     "next": "canary",

packages/now-next/test/fixtures/11-export-clean-urls/package.json

@@ -1,6 +1,6 @@
 {
   "scripts": {
-    "build": "next build && next export"
+    "vercel-build": "next build && next export"
   },
   "dependencies": {
     "next": "canary",

packages/now-node/src/index.ts

@@ -361,10 +361,12 @@ export async function build({
     meta,
   });
 
-  debug('Running user script...');
-  const runScriptTime = Date.now();
-  await runPackageJsonScript(entrypointFsDirname, 'now-build', spawnOpts);
-  debug(`Script complete [${Date.now() - runScriptTime}ms]`);
+  await runPackageJsonScript(
+    entrypointFsDirname,
+    // Don't consider "build" script since its intended for frontend code
+    ['vercel-build', 'now-build'],
+    spawnOpts
+  );
 
   debug('Tracing input files...');
   const traceTime = Date.now();

packages/now-static-build/build.sh

@@ -1,4 +1,8 @@
 #!/bin/bash
 set -euo pipefail
 
+# Start fresh
+rm -rf dist
+
+# Build with `ncc`
 ncc build src/index.ts -e @vercel/build-utils -e @now/build-utils -o dist

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

@@ -264,7 +264,6 @@ export async function build({
   const pkg = getPkg(entrypoint, workPath);
 
   const devScript = pkg ? getScriptName(pkg, 'dev', config) : null;
-  const buildScript = pkg ? getScriptName(pkg, 'build', config) : null;
 
   const framework = getFramework(config, pkg);
 
@@ -431,8 +430,6 @@ export async function build({
 
       if (buildCommand) {
         debug(`Executing "${buildCommand}"`);
-      } else {
-        debug(`Running "${buildScript}" in "${entrypoint}"`);
       }
 
       const found =
@@ -441,12 +438,16 @@ export async function build({
               ...spawnOpts,
               cwd: entrypointDir,
             })
-          : await runPackageJsonScript(entrypointDir, buildScript!, spawnOpts);
+          : await runPackageJsonScript(
+              entrypointDir,
+              ['vercel-build', 'now-build', 'build'],
+              spawnOpts
+            );
 
       if (!found) {
         throw new Error(
           `Missing required "${
-            buildCommand || buildScript
+            buildCommand || 'vercel-build'
           }" script in "${entrypoint}"`
         );
       }

packages/now-static-build/test/fixtures/08-hundreds/package.json

@@ -1,5 +1,5 @@
 {
   "scripts": {
-    "now-build": "mkdir dist && node build.js"
+    "vercel-build": "mkdir dist && node build.js"
   }
 }

packages/now-static-build/test/integration.test.js

@@ -35,7 +35,7 @@ const testsThatFailToBuild = new Map([
   ['05-empty-dist-dir', 'The Output Directory "dist" is empty.'],
   [
     '06-missing-script',
-    'Missing required "now-build" script in "package.json"',
+    'Missing required "vercel-build" script in "package.json"',
   ],
   ['07-nonzero-sh', 'Command "./build.sh" exited with 1'],
   [