Lab submission

.vscode/launch.json

@@ -0,0 +1,15 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "chrome",
+            "request": "launch",
+            "name": "Launch Chrome against localhost",
+            "url": "http://localhost:8080",
+            "webRoot": "${workspaceFolder}"
+        }
+    ]
+}

app.js

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+const express = require('express');
+const path = require('path');
+const EventEmitter = require('events');
+
+const port = process.env.PORT || 3000;
+const chatEmitter = new EventEmitter();
+
+function respondText(req, res) {
+    res.setHeader('Content-Type', 'text/plain');
+    res.end('hi');
+}
+
+function respondJson(req, res) {
+    res.json({
+        text: 'hi',
+        numbers: [
+            1, 2, 3
+        ],
+    });
+}
+
+function respondNotFound(req, res) {
+    res.writeHead(404, { 'Content-Type': 'text/plain' });
+    res.end('Not Found');
+}
+
+function respondEcho(req, res) {
+    const { input = '' } = req.query;
+
+    res.json({
+      normal: input,
+      shouty: input.toUpperCase(),
+      charCount: input.length,
+      backwards: input.split('').reverse().join(''),
+    });
+}
+
+function chatApp(req, res) {
+    res.sendFile(path.join(__dirname, '/chat.html'));
+}
+
+function respondChat (req, res) {
+    const { message } = req.query;
+
+    chatEmitter.emit('message', message);
+    res.end();
+}
+
+function respondSSE (req, res) {
+    res.writeHead(200, {
+      'Content-Type': 'text/event-stream',
+      'Connection': 'keep-alive',
+    });
+
+    const onMessage = message => res.write(`data: ${message}\n\n`);
+
+    chatEmitter.on('message', onMessage);
+    res.on('close', () => {
+      chatEmitter.off('message', onMessage);
+    });
+}
+
+const app = express();
+app.use(express.static(__dirname + '/public'));
+app.get('/', chatApp);
+app.get('/chat', respondChat);
+app.get('/sse', respondSSE);
+
+
+app.listen(port, () => {
+  console.log(`Listening on port ${port}`);
+});