feat: support throwing responses in upgrade hook (#91)

Co-authored-by: Pooya Parsa <pooya@pi0.io>

src/adapters/bun.ts

@@ -31,17 +31,18 @@ export default defineWebSocketAdapter<BunAdapter, BunOptions>(
     return {
       ...adapterUtils(peers),
       async handleUpgrade(request, server) {
-        const res = await hooks.callHook("upgrade", request);
-        if (res instanceof Response) {
-          return res;
+        const { upgradeHeaders, endResponse } = await hooks.upgrade(request);
+        if (endResponse) {
+          return endResponse;
         }
         const upgradeOK = server.upgrade(request, {
           data: {
             server,
             request,
           } satisfies ContextData,
-          headers: res?.headers,
+          headers: upgradeHeaders,
         });
+
         if (!upgradeOK) {
           return new Response("Upgrade failed", { status: 500 });
         }

src/adapters/cloudflare-durable.ts

@@ -31,10 +31,13 @@ export default defineWebSocketAdapter<
       // placeholder
     },
     handleDurableUpgrade: async (obj, request) => {
-      const res = await hooks.callHook("upgrade", request as Request);
-      if (res instanceof Response) {
-        return res;
+      const { upgradeHeaders, endResponse } = await hooks.upgrade(
+        request as Request,
+      );
+      if (endResponse) {
+        return endResponse;
       }
+
       const pair = new WebSocketPair();
       const client = pair[0];
       const server = pair[1];
@@ -46,11 +49,12 @@ export default defineWebSocketAdapter<
       peers.add(peer);
       (obj as DurableObjectPub).ctx.acceptWebSocket(server);
       await hooks.callHook("open", peer);
+
       // eslint-disable-next-line unicorn/no-null
       return new Response(null, {
         status: 101,
         webSocket: client,
-        headers: res?.headers,
+        headers: upgradeHeaders,
       });
     },
     handleDurableMessage: async (obj, ws, message) => {

src/adapters/cloudflare.ts

@@ -33,13 +33,13 @@ export default defineWebSocketAdapter<CloudflareAdapter, CloudflareOptions>(
     return {
       ...adapterUtils(peers),
       handleUpgrade: async (request, env, context) => {
-        const res = await hooks.callHook(
-          "upgrade",
+        const { upgradeHeaders, endResponse } = await hooks.upgrade(
           request as unknown as Request,
         );
-        if (res instanceof Response) {
-          return res;
+        if (endResponse) {
+          return endResponse as unknown as _cf.Response;
         }
+
         const pair = new WebSocketPair();
         const client = pair[0];
         const server = pair[1];
@@ -73,7 +73,7 @@ export default defineWebSocketAdapter<CloudflareAdapter, CloudflareOptions>(
         return new Response(null, {
           status: 101,
           webSocket: client,
-          headers: res?.headers,
+          headers: upgradeHeaders,
         });
       },
     };

src/adapters/deno.ts

@@ -31,13 +31,14 @@ export default defineWebSocketAdapter<DenoAdapter, DenoOptions>(
     return {
       ...adapterUtils(peers),
       handleUpgrade: async (request, info) => {
-        const res = await hooks.callHook("upgrade", request);
-        if (res instanceof Response) {
-          return res;
+        const { upgradeHeaders, endResponse } = await hooks.upgrade(request);
+        if (endResponse) {
+          return endResponse;
         }
+
         const upgrade = Deno.upgradeWebSocket(request, {
           // @ts-expect-error https://github.com/denoland/deno/pull/22242
-          headers: res?.headers,
+          headers: upgradeHeaders,
         });
         const peer = new DenoPeer({
           ws: upgrade.socket,

src/adapters/node.ts

@@ -86,12 +86,14 @@ export default defineWebSocketAdapter<NodeAdapter, NodeOptions>(
       ...adapterUtils(peers),
       handleUpgrade: async (nodeReq, socket, head) => {
         const request = new NodeReqProxy(nodeReq);
-        const res = await hooks.callHook("upgrade", request);
-        if (res instanceof Response) {
-          return sendResponse(socket, res);
+
+        const { upgradeHeaders, endResponse } = await hooks.upgrade(request);
+        if (endResponse) {
+          return sendResponse(socket, endResponse);
         }
+
         (nodeReq as AugmentedReq)._request = request;
-        (nodeReq as AugmentedReq)._upgradeHeaders = res?.headers;
+        (nodeReq as AugmentedReq)._upgradeHeaders = upgradeHeaders;
         wss.handleUpgrade(nodeReq, socket, head, (ws) => {
           wss.emit("connection", ws, nodeReq);
         });

src/adapters/sse.ts

@@ -27,9 +27,9 @@ export default defineWebSocketAdapter<SSEAdapter, SSEOptions>((opts = {}) => {
   return {
     ...adapterUtils(peers),
     fetch: async (request: Request) => {
-      const _res = await hooks.callHook("upgrade", request);
-      if (_res instanceof Response) {
-        return _res;
+      const { upgradeHeaders, endResponse } = await hooks.upgrade(request);
+      if (endResponse) {
+        return endResponse;
       }
 
       let peer: SSEPeer;
@@ -73,17 +73,19 @@ export default defineWebSocketAdapter<SSEAdapter, SSEOptions>((opts = {}) => {
         "Cache-Control": "no-cache",
         Connection: "keep-alive",
       };
+
       if (opts.bidir) {
         headers["x-crossws-id"] = peer.id;
       }
-      if (_res?.headers) {
+
+      if (upgradeHeaders) {
         headers = new Headers(headers);
-        for (const [key, value] of new Headers(_res.headers)) {
+        for (const [key, value] of new Headers(upgradeHeaders)) {
           headers.set(key, value);
         }
       }
 
-      return new Response(peer._sseStream, { ..._res, headers });
+      return new Response(peer._sseStream, { headers });
     },
   };
 });

src/adapters/uws.ts

@@ -75,20 +75,18 @@ export default defineWebSocketAdapter<UWSAdapter, UWSOptions>(
           res.onAborted(() => {
             aborted = true;
           });
-          const _res = await hooks.callHook("upgrade", new UWSReqProxy(req));
-          if (aborted) {
-            return;
-          }
-          if (_res instanceof Response) {
-            res.writeStatus(`${_res.status} ${_res.statusText}`);
-            for (const [key, value] of _res.headers) {
+
+          const { upgradeHeaders, endResponse } = await hooks.upgrade(
+            new UWSReqProxy(req),
+          );
+          if (endResponse) {
+            res.writeStatus(`${endResponse.status} ${endResponse.statusText}`);
+            for (const [key, value] of endResponse.headers) {
               res.writeHeader(key, value);
             }
-            if (_res.body) {
-              for await (const chunk of _res.body) {
-                if (aborted) {
-                  break;
-                }
+            if (endResponse.body) {
+              for await (const chunk of endResponse.body) {
+                if (aborted) break;
                 res.write(chunk);
               }
             }
@@ -97,9 +95,16 @@ export default defineWebSocketAdapter<UWSAdapter, UWSOptions>(
             }
             return;
           }
+
+          if (aborted) {
+            return;
+          }
+
           res.writeStatus("101 Switching Protocols");
-          if (_res?.headers) {
-            for (const [key, value] of new Headers(_res.headers)) {
+          if (upgradeHeaders) {
+            // prettier-ignore
+            const headers = upgradeHeaders instanceof Headers ? upgradeHeaders : new Headers(upgradeHeaders);
+            for (const [key, value] of headers) {
               res.writeHeader(key, value);
             }
           }

src/hooks.ts

@@ -39,6 +39,32 @@ export class AdapterHookable {
       },
     ) as Promise<any>;
   }
+
+  async upgrade(request: UpgradeRequest): Promise<{
+    upgradeHeaders?: HeadersInit;
+    endResponse?: Response;
+  }> {
+    try {
+      const res = await this.callHook("upgrade", request);
+      if (!res) {
+        return {};
+      }
+      if ((res as Response).ok === false) {
+        return { endResponse: res as Response };
+      }
+      if (res.headers) {
+        return {
+          upgradeHeaders: res.headers,
+        };
+      }
+    } catch (error) {
+      if (error instanceof Response) {
+        return { endResponse: error };
+      }
+      throw error;
+    }
+    return {};
+  }
 }
 
 // --- types ---
@@ -60,16 +86,23 @@ type HookFn<ArgsT extends any[] = any, RT = void> = (
   ...args: ArgsT
 ) => MaybePromise<RT>;
 
-export interface Hooks {
-  /** Upgrading */
-  upgrade: (
-    request:
+export type UpgradeRequest =
   | Request
   | {
       url: string;
       headers: Headers;
-        },
-  ) => MaybePromise<Response | ResponseInit | void>;
+    };
+
+export interface Hooks {
+  /** Upgrading */
+  /**
+   *
+   * @param request
+   * @throws {Response}
+   */
+  upgrade: (
+    request: UpgradeRequest,
+  ) => MaybePromise<Response | ResponseInit | undefined>;
 
   /** A message is received */
   message: (peer: Peer, message: Message) => MaybePromise<void>;