add stricter type for ProxyServer.web and ProxyServer.ws

Author: sapphi-red

lib/http-proxy/index.ts

@@ -1,5 +1,6 @@
 import * as http from "http";
 import * as https from "https";
+import * as net from "net";
 import { WEB_PASSES } from "./passes/web-incoming";
 import { WS_PASSES } from "./passes/ws-incoming";
 import { EventEmitter } from "events";
@@ -84,6 +85,14 @@ export interface ServerOptions {
   buffer?: Stream;
 }
 
+export type ErrorCallback =
+  (
+    err: Error,
+    req: http.IncomingMessage,
+    res: http.ServerResponse | net.Socket,
+    target?: ProxyTargetUrl,
+  ) => void;
+
 export class ProxyServer extends EventEmitter {
   /**
    * Used for proxying WS(S) requests
@@ -92,14 +101,43 @@ export class ProxyServer extends EventEmitter {
    * @param head - Client head.
    * @param options - Additional options.
    */
-  public readonly ws;
+  public readonly ws: (
+    ...args:
+      [
+        req: http.IncomingMessage,
+        socket: any,
+        head: any,
+        options?: ServerOptions,
+        callback?: ErrorCallback,
+      ]
+    | [
+        req: http.IncomingMessage,
+        socket: any,
+        head: any,
+        callback?: ErrorCallback,
+      ]
+  ) => void;
+
   /**
    * Used for proxying regular HTTP(S) requests
    * @param req - Client request.
    * @param res - Client response.
    * @param options - Additional options.
    */
-  public readonly web;
+  public readonly web: (
+    ...args:
+      [
+        req: http.IncomingMessage,
+        res: http.ServerResponse,
+        options: ServerOptions,
+        callback?: ErrorCallback,
+      ]
+    | [
+        req: http.IncomingMessage,
+        res: http.ServerResponse,
+        callback?: ErrorCallback
+      ]
+  ) => void;
 
   private options: ServerOptions;
   private webPasses;

lib/index.ts

@@ -1,6 +1,18 @@
-import { ProxyServer, type ServerOptions, type ProxyTarget, type ProxyTargetUrl } from "./http-proxy/index";
-export { ProxyServer, type ServerOptions, type ProxyTarget, type ProxyTargetUrl };
-export { numOpenSockets } from "./http-proxy/passes/ws-incoming";
+import {
+  ProxyServer,
+  type ServerOptions,
+  type ProxyTarget,
+  type ProxyTargetUrl,
+  type ErrorCallback,
+} from './http-proxy/index';
+export {
+  ProxyServer,
+  type ServerOptions,
+  type ProxyTarget,
+  type ProxyTargetUrl,
+  type ErrorCallback,
+};
+export { numOpenSockets } from './http-proxy/passes/ws-incoming';
 
 /**
  * Creates the proxy server.

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

@@ -213,7 +213,7 @@ describe("#createProxyServer.web() using own http server", () => {
     function requestHandler(req, res) {
       proxy.web(req, res, (err) => {
         proxyServer.close();
-        expect(err.code).toEqual("ECONNREFUSED");
+        expect((err as NodeJS.ErrnoException).code).toEqual("ECONNREFUSED");
         done();
       });
     }