refactor: migrate from node:http to Express with Express.js tests

src/bin/server.ts

@@ -0,0 +1,5 @@
+import { app, port } from "../index.js";
+
+app.listen(port, () => {
+  console.log(`demo-app listening on :${port}`);
+});

src/index.test.ts

@@ -1,7 +1,33 @@
-import test from "node:test";
-import assert from "node:assert/strict";
+import { describe, it, expect } from "vitest";
+import request from "supertest";
+import { app } from "./index.js";
 import { greeting } from "./greeting.js";
 
-test("greeting mentions the homelab", () => {
-  assert.match(greeting(), /homelab/);
+describe("greeting", () => {
+  it("mentions the homelab", () => {
+    expect(greeting()).toMatch(/homelab/);
+  });
+});
+
+describe("GET /healthz", () => {
+  it("returns 200 ok", async () => {
+    const res = await request(app).get("/healthz");
+    expect(res.status).toBe(200);
+    expect(res.text).toBe("ok");
+    expect(res.type).toBe("text/plain");
+  });
+});
+
+describe("GET /", () => {
+  it("returns service info", async () => {
+    const res = await request(app).get("/");
+    expect(res.status).toBe(200);
+    expect(res.body).toMatchObject({
+      service: "demo-app",
+      message: "Hello from the homelab pipeline!",
+      sha: expect.any(String),
+      pod: expect.any(String),
+      time: expect.any(String),
+    });
+  });
 });

src/index.ts

@@ -1,32 +1,23 @@
-import { createServer } from "node:http";
+import express from "express";
 import { hostname } from "node:os";
 import { greeting } from "./greeting.js";
 
+const app = express();
 const port = Number(process.env.PORT ?? 3000);
 const sha = process.env.GIT_SHA ?? "dev";
 
-const server = createServer((req, res) => {
-  if (req.url === "/healthz") {
-    res.writeHead(200, { "content-type": "text/plain" });
-    res.end("ok");
-    return;
-  }
-  res.writeHead(200, { "content-type": "application/json" });
-  res.end(
-    JSON.stringify(
-      {
-        service: "demo-app",
-        message: greeting(),
-        sha,
-        pod: hostname(),
-        time: new Date().toISOString(),
-      },
-      null,
-      2,
-    ) + "\n",
-  );
+app.get("/healthz", (_req, res) => {
+  res.type("text/plain").send("ok");
 });
 
-server.listen(port, () => {
-  console.log(`demo-app ${sha} listening on :${port}`);
+app.get("/", (_req, res) => {
+  res.json({
+    service: "demo-app",
+    message: greeting(),
+    sha,
+    pod: hostname(),
+    time: new Date().toISOString(),
+  });
 });
+
+export { app, port };