From ba70685e592d991e2ccf0b979af7d29d0fb68fd0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mert=20Can=20Alt=C4=B1n?= <mertgold60@gmail.com>
Date: Fri, 26 Jan 2024 21:09:44 +0300
Subject: [PATCH] add webSocket example (#2626)

* add webSocket example

* lint

* refactor: Organize proxy-related code into separate files

* refactor: Organize proxy-related code into separate files

* feat: move websocket instance to separate file

---------

Co-authored-by: Mert Can Altin <mert.altin@trendyol.com>
---
 examples/proxy/index.js     |  2 -
 examples/proxy/websocket.js | 89 +++++++++++++++++++++++++++++++++++++
 2 files changed, 89 insertions(+), 2 deletions(-)
 create mode 100644 examples/proxy/websocket.js

diff --git a/examples/proxy/index.js b/examples/proxy/index.js
index 5f35049203e..4cf8bc61b16 100644
--- a/examples/proxy/index.js
+++ b/examples/proxy/index.js
@@ -45,5 +45,3 @@ async function run () {
 }
 
 run()
-
-// TODO: Add websocket example.
diff --git a/examples/proxy/websocket.js b/examples/proxy/websocket.js
new file mode 100644
index 00000000000..324d0531c57
--- /dev/null
+++ b/examples/proxy/websocket.js
@@ -0,0 +1,89 @@
+const { Pool, Client } = require('../../')
+const http = require('http')
+const proxy = require('./proxy')
+const WebSocket = require('ws')
+
+const pool = new Pool('http://localhost:4001', {
+  connections: 256,
+  pipelining: 1
+})
+
+function createWebSocketServer () {
+  const wss = new WebSocket.Server({ noServer: true })
+
+  wss.on('connection', ws => {
+    ws.on('message', message => {
+      console.log(`Received message: ${message}`)
+      ws.send('Received your message!')
+    })
+  })
+
+  return wss
+}
+
+async function run () {
+  await Promise.all([
+    new Promise(resolve => {
+      // Proxy
+      http.createServer((req, res) => {
+        proxy({ req, res, proxyName: 'example' }, pool).catch(err => {
+          if (res.headersSent) {
+            res.destroy(err)
+          } else {
+            for (const name of res.getHeaderNames()) {
+              res.removeHeader(name)
+            }
+            res.statusCode = err.statusCode || 500
+            res.end()
+          }
+        })
+      }).listen(4000, resolve)
+    }),
+    new Promise(resolve => {
+      // Upstream
+      http.createServer((req, res) => {
+        res.end('hello world')
+      }).listen(4001, resolve)
+    }),
+    new Promise(resolve => {
+      // WebSocket server
+      const server = http.createServer((req, res) => {
+        res.writeHead(200, { 'Content-Type': 'text/plain' })
+        res.end('WebSocket server is running!')
+      })
+
+      const wss = createWebSocketServer()
+
+      server.on('upgrade', (request, socket, head) => {
+        wss.handleUpgrade(request, socket, head, ws => {
+          wss.emit('connection', ws, request)
+        })
+      })
+
+      server.listen(4002, resolve)
+    })
+  ])
+
+  const client = new Client('http://localhost:4000')
+  const { body } = await client.request({
+    method: 'GET',
+    path: '/'
+  })
+
+  for await (const chunk of body) {
+    console.log(String(chunk))
+  }
+
+  // WebSocket client
+  const ws = new WebSocket('ws://localhost:4002')
+  ws.on('open', () => {
+    ws.send('Hello, WebSocket Server!')
+  })
+
+  ws.on('message', message => {
+    console.log(`WebSocket Server says: ${message}`)
+    ws.close()
+  })
+}
+
+run()