fully proxy HTTP response

applies full web-outgoing passes

needs to declare an EditableResponse subset of Response
in order to mock it for the proxy response

Author: minrk

lib/http-proxy/passes/web-incoming.ts

@@ -9,7 +9,7 @@ The names of passes are exported as WEB_PASSES from this module.
 
 import * as http from "node:http";
 import * as https from "node:https";
-import { OUTGOING_PASSES } from "./web-outgoing";
+import { OUTGOING_PASSES, EditableResponse } from "./web-outgoing";
 import * as common from "../common";
 import * as followRedirects from "follow-redirects";
 import {
@@ -164,7 +164,7 @@ export function stream(req: Request, res: Response, options: NormalizedServerOpt
     if (!res.headersSent && !options.selfHandleResponse) {
       for (const pass of web_o) {
         // note: none of these return anything
-        pass(req, res, proxyRes, options as NormalizedServerOptions & { target: NormalizeProxyTarget<ProxyTarget> });
+        pass(req, res as EditableResponse, proxyRes, options as NormalizedServerOptions & { target: NormalizeProxyTarget<ProxyTarget> });
       }
     }
 

lib/http-proxy/passes/web-outgoing.ts

@@ -11,16 +11,24 @@ to not return anything.
 
 import type { NormalizedServerOptions, NormalizeProxyTarget, ProxyTarget } from "..";
 import * as common from "../common";
-import type { Request, Response, ProxyResponse } from "./web-incoming";
+import type { Request, ProxyResponse } from "./web-incoming";
 
 const redirectRegex = /^201|30(1|2|7|8)$/;
 
+// interface for subset of Response that's actually used here
+// needed for running outgoing passes on MockResponse in ws-incoming
+export interface EditableResponse {
+  statusCode: number;
+  statusMessage: string;
+  setHeader(key: string, value: string | string[]): this;
+}
+
 // <--
 
 // If is a HTTP 1.0 request, remove chunk headers
 export function removeChunked(
   req: Request,
-  _res: Response,
+  _res: EditableResponse,
   // Response object from the proxy request
   proxyRes: ProxyResponse,
 ) {
@@ -33,7 +41,7 @@ export function removeChunked(
 // or if connection header not present, then use `keep-alive`
 export function setConnection(
   req: Request,
-  _res: Response,
+  _res: EditableResponse,
   // Response object from the proxy request
   proxyRes: ProxyResponse,
 ) {
@@ -46,7 +54,7 @@ export function setConnection(
 
 export function setRedirectHostRewrite(
   req: Request,
-  _res: Response,
+  _res: EditableResponse,
   proxyRes: ProxyResponse,
   options: NormalizedServerOptions & { target: NormalizeProxyTarget<ProxyTarget> },
 ) {
@@ -84,7 +92,7 @@ export function setRedirectHostRewrite(
 export function writeHeaders(
   _req: Request,
   // Response to set headers in
-  res: Response,
+  res: EditableResponse,
   // Response object from the proxy request
   proxyRes: ProxyResponse,
   // options.cookieDomainRewrite: Config to rewrite cookie domain
@@ -147,7 +155,7 @@ export function writeHeaders(
 // Set the statusCode from the proxyResponse
 export function writeStatusCode(
   _req: Request,
-  res: Response,
+  res: EditableResponse,
   proxyRes: ProxyResponse,
 ) {
   // From Node.js docs: response.writeHead(statusCode[, statusMessage][, headers])

lib/http-proxy/passes/ws-incoming.ts

@@ -12,11 +12,13 @@ import * as http from "node:http";
 import * as https from "node:https";
 import * as common from "../common";
 import type { Request, ProxyResponse } from "./web-incoming";
+import { OUTGOING_PASSES, EditableResponse } from "./web-outgoing";
 import type { Socket } from "node:net";
 import debug from "debug";
-import type { NormalizedServerOptions, ProxyServer } from "..";
+import type { NormalizedServerOptions, NormalizeProxyTarget, ProxyServer, ProxyTarget } from "..";
 
 const log = debug("http-proxy-3:ws-incoming");
+const web_o = Object.values(OUTGOING_PASSES);
 
 function createSocketCounter(name: string) {
   let sockets = new Set<number>();
@@ -55,6 +57,26 @@ function createSocketCounter(name: string) {
 const socketCounter = createSocketCounter("socket");
 const proxySocketCounter = createSocketCounter("proxySocket");
 
+/* MockResponse
+   when a websocket gets a regular HTTP Response,
+   apply proxied headers
+*/
+class MockResponse implements EditableResponse {
+  constructor() {
+    this.headers = {};
+    this.statusCode = 200
+    this.statusMessage = "";
+  }
+  public headers: { [key: string]: string};
+  public statusCode: number;
+  public statusMessage: string;
+  
+  setHeader(key: string, value: string)  {
+    this.headers[key] = value;
+    return this;
+  };
+}
+
 export function numOpenSockets(): number {
   return socketCounter() + proxySocketCounter();
 }
@@ -219,7 +241,7 @@ export function stream(
     // which may be another leak type situation and definitely doesn't work for unit testing.
     socket.destroySoon();
   }
-  
+
   // if we get a response, backend is not a websocket endpoint,
   // relay HTTP response and close the socket
   proxyReq.on("response", (proxyRes: ProxyResponse) => {
@@ -229,9 +251,18 @@ export function stream(
           statusMessage: proxyRes.statusMessage,
         }
     );
+
+    const res = new MockResponse();
+    for (const pass of web_o) {
+      // note: none of these return anything
+      pass(req, res as EditableResponse, proxyRes, options as NormalizedServerOptions & { target: NormalizeProxyTarget<ProxyTarget> });
+    }
+    // avoid Invalid character error in chunk size
+    delete res.headers['transfer-encoding'];
+
     const proxyHead = createHttpHeader(
-      `HTTP/1.1 ${proxyRes.statusCode} ${proxyRes.statusMessage}`,
-      {"Connection": "close"},
+      `HTTP/${req.httpVersion} ${proxyRes.statusCode} ${proxyRes.statusMessage}`,
+      res.headers,
     );
     if (!socket.destroyed) {
       socket.write(proxyHead);