modify response middleware unit test

Author: williamstein

examples/middleware/modifyResponse-middleware.js

@@ -0,0 +1,55 @@
+/*
+modify-response-middleware.test.ts -- Middleware which modifies response
+
+pnpm test modify-response-middleware.test.ts
+*/
+
+import * as httpProxy from "../..";
+import * as http from "http";
+import getPort from "../get-port";
+import connect from "connect";
+
+describe("Using the connect-gzip middleware from connect with http-proxy-3", () => {
+  let ports;
+  it("gets ports", async () => {
+    ports = { http: await getPort(), proxy: await getPort() };
+  });
+
+  let servers: any = {};
+  it("creates target http server", () => {
+    servers.http = http.createServer(async (_req, res) => {
+      res.writeHead(200, { "Content-Type": "text/html" });
+      res.write("i am hosted at http-party");
+      res.end();
+    });
+    servers.http.listen(ports.http);
+  });
+
+  it("creates connect server that uses a proxy as middleware to actually satisfy the request, after applying compression", () => {
+    const proxy = httpProxy.createProxyServer({
+      target: `http://localhost:${ports.http}`,
+    });
+    const rewrite = (_req, res, next) => {
+      const _write = res.write;
+      res.write = (data) => {
+        _write.call(res, data.toString().replace("http-party", "cocalc"));
+      };
+      next();
+    };
+    servers.app = connect().use(rewrite).use(proxy.web).listen(ports.proxy);
+  });
+
+  it("test the http server", async () => {
+    const a = await (await fetch(`http://localhost:${ports.http}`)).text();
+    expect(a).toContain("i am hosted at http-party");
+  });
+
+  it("test the proxy server", async () => {
+    const a = await (await fetch(`http://localhost:${ports.proxy}`)).text();
+    expect(a).toContain("i am hosted at cocalc");
+  });
+
+  it("Clean up", () => {
+    Object.values(servers).map((x: any) => x?.close());
+  });
+});