سرور Deloy SocketIO با استفاده از Docker و Nginx Load Balancer (+SSL)

/socket-server
|-- src/
    |-- index.js
    |-- loggers/
|-- .env
|-- .env_one
|-- .env_two
|-- .env_three
|-- .env_four
|-- Dockerfile
|-- docker-compose.yaml
|-- nginx.conf
|-- package.json
|-- yarn.lock

import express from "express";
import { createServer } from "http";
import { Redis } from "ioredis";
import { Server } from "socket.io";
import { createAdapter } from "@socket.io/redis-adapter";
import logger from "./logger/winston_logger.js";
import bodyParser from "body-parser";

const app = express();
const http = createServer(app);

const port = process.env.PORT;
const serverName = process.env.SERVER_NAME;
const redisHost = process.env.REDIS_HOST;
const redisPort = process.env.REDIS_PORT;
const socketKey = process.env.SECRET_KEY;

let numConnectedSockets = 0;

const pubClient = new Redis({
  host: redisHost,
  port: redisPort,
  keyPrefix: "myapp",
});
const subClient = pubClient.duplicate();

logger.info(
  `Redis client connected to ${redisHost}:${redisPort} with status: pub: ${pubClient.status} sub: ${subClient.status}`
);

// listen to redis connection status
pubClient.on("connect", () => {
  logger.info("Redis pub client connected!");
});

subClient.on("connect", () => {
  logger.info("Redis sub client connected!");
});

// create socket io server with adapter
// add your other services here
const io = new Server(http, {
  cors: {
    origin: ["http://localhost:3000", "http://localhost:8020"],
    methods: ["GET", "POST"],
  },
  adapter: createAdapter(pubClient, subClient),
});

// express listen to port
http.listen(port, () => {
  logger.info(`Server ${serverName} is running on port ${port}`);
});

// socket io connection
io.on("connection", (socket) => {
  logger.info(`User connected: ${socket.id} to socket server ${serverName}`);

  socket.emit("hi", {
    serverName: serverName,
    msg: `Hello from socket server ${serverName}!`,
  });

  // socket io events
  socket.on("disconnect", () => {
    numConnectedSockets--;
    logger.info(`User disconnected: ${socket.id} from ${serverName}!`);
  });

  socket.on("hello", (msg) => {
    logger.info(`Receive a hello from ${socket.id} with ${msg}`);
    logger.info(`server socket key is ${socketKey}`);
    logger.info(`test socket key vs msg is ${socketKey} vs ${msg}`);
    if (msg) {
      if (msg === socketKey) {
        logger.info(`User ${socket.id} sent the correct key. Welcome!`);
        socket.emit("introduce_yourself", {
          serverName: serverName,
          msg: `Please introduce yourself!`,
        });
      } else {
        socket.disconnect();
      }
    } else {
      socket.disconnect();
    }
  });

  socket.on("introduction", (msg) => {
    logger.info(`Receive a introduction from ${socket.id}`);
    if (msg) {
      const { name, token } = msg;
      if (!name || !token) {
        logger.error(
          `User ${socket.id} did not introduce themselves correctly!. Disconnecting...`
        );

        // disconnect user
        socket.disconnect();
        return;
      }

      logger.info(
        `User ${socket.id} introduced as ${name} with token ${token}`
      );

      // validate name and token
      let isAuthorized = false;
      if (name === "admin" && token === "admin") {
        isAuthorized = true;
        logger.info(`User ${socket.id} is an admin!`);
      }

      if (token === socketKey) {
        logger.info(`User ${socket.id} is an authenticated user!`);
        isAuthorized = true;
      }

      if (isAuthorized === false) {
        logger.error(
          `User ${name} with socket id ${socket.id} is not authorized. Disconnecting...`
        );

        // disconnect user
        socket.disconnect();
        return;
      }

      numConnectedSockets++;
    } else {
      logger.error(
        `Can not get the message from ${socket.id} while introduction. Disconnecting...`
      );

      logger.error({
        msg,
      });

      // disconnect user
      socket.disconnect();
    }
  });

  socket.on("log_event", (data) => {
    socket.broadcast.emit("broadcast_log_event", {
      serverName: serverName,
      msg: data,
    });
  });
});

// error handling
io.on("error", (error) => {
  logger.error(`Error: ${error}`);
});

app.use(bodyParser.json());

// express default route
app.get("/heartbeat", (req, res) => {
  res.sendStatus(200);
});

// base url
app.get("/", (_, res) => {
  winstonLogger.info(`base endpoint called`);
  res.status(200).json({
    error: false,
    msg: "Base endpoint works",
  });
});

app.get("/", (req, res) => {
  res.status(200).json({
    message: `Welcome to socket server ${serverName}`,
    socketConnected: numConnectedSockets,
  });
});

# Reference: https://www.nginx.com/resources/wiki/start/topics/examples/full/

worker_processes 4;

events {
  worker_connections 1024;
}

http {
  server {
    listen 80;

    location / {
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $host;

      proxy_pass http://nodes;

      # enable WebSockets
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection "upgrade";
    }
  }

  upstream nodes {
    # enable sticky session with either "hash" (uses the complete IP address)
    hash $remote_addr consistent;
    # or "ip_hash" (uses the first three octets of the client IPv4 address, or the entire IPv6 address)
    # ip_hash;
    # or "sticky" (needs commercial subscription)
    # sticky cookie srv_id expires=1h domain=.example.com path=/;

    server server-one:3000;
    server server-two:3000;
    server server-three:3000;
    server server-four:3000;
  }
}

# Use the official Node.js 21 image as the base image
FROM node:21-alpine

# Set the working directory inside the container
WORKDIR /app

# Copy package.json and package-lock.json to the working directory
COPY package*.json ./

# Install the app dependencies
RUN yarn install --production=true

# Copy the rest of the app source code to the working directory
COPY . .

# Set the non-root user to run the application
USER node

# Expose the port on which the app will run
EXPOSE 3000

# Start the application
CMD node --env-file=.env src/index.js

services:
  nginx:
    image: nginx:alpine
    volumes:
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
    links:
      - server-one
      - server-two
      - server-three
      - server-four
    ports:
      - "3002:80"

  server-one:
    build: .
    expose:
      - "3000"
    env_file:
      - .env_one
    restart: always

  server-two:
    build: .
    expose:
      - "3000"
    env_file:
      - .env_two
    restart: always

  server-three:
    build: .
    expose:
      - "3000"
    env_file:
      - .env_three
    restart: always

  server-four:
    build: .
    expose:
      - "3000"
    env_file:
      - .env_four
    restart: always

location /socket.io/ {
   proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
   proxy_set_header Host $host;

   # the port of the nginx in docker compose
   proxy_pass http://localhost:3002;

   # enable WebSockets
   proxy_http_version 1.1;
   proxy_set_header Upgrade $http_upgrade;
   proxy_set_header Connection "upgrade";
}

import 'package:socket_io_client/socket_io_client.dart' as io;

// create a new socket instance
socket = io.io(socketServer, {
  'transports': ['websocket'],
  'secure': true,
});

ocket.onConnect((_) {
  debugPrint('get connected to the server $socketServer');
});

socket.onError((error) {
  debugPrint('error: $error');
});

socket.onDisconnect((_) => debugPrint('disconnected from $socketServer'));