How to reverse proxy a Socket.io app with Nginx? - node.js

Question

I want to reverse proxy the official Socket.io chat demo with Nginx.
So, this is the server file:
// Setup basic express server
var express = require('express');
var app = express();
var server = require('http').createServer(app);
var io = require('../..')(server);
var port = process.env.PORT || 3000;
server.listen(port, function () {
console.log('Server listening at port %d', port);
});
// Routing
app.use(express.static(__dirname + '/public'));
// Chatroom
var numUsers = 0;
io.on('connection', function (socket) {
var addedUser = false;
// when the client emits 'new message', this listens and executes
socket.on('new message', function (data) {
// we tell the client to execute 'new message'
socket.broadcast.emit('new message', {
username: socket.username,
message: data
});
});
// when the client emits 'add user', this listens and executes
socket.on('add user', function (username) {
if (addedUser) return;
// we store the username in the socket session for this client
socket.username = username;
++numUsers;
addedUser = true;
socket.emit('login', {
numUsers: numUsers
});
// echo globally (all clients) that a person has connected
socket.broadcast.emit('user joined', {
username: socket.username,
numUsers: numUsers
});
});
// when the client emits 'typing', we broadcast it to others
socket.on('typing', function () {
socket.broadcast.emit('typing', {
username: socket.username
});
});
// when the client emits 'stop typing', we broadcast it to others
socket.on('stop typing', function () {
socket.broadcast.emit('stop typing', {
username: socket.username
});
});
// when the user disconnects.. perform this
socket.on('disconnect', function () {
if (addedUser) {
--numUsers;
// echo globally that this client has left
socket.broadcast.emit('user left', {
username: socket.username,
numUsers: numUsers
});
}
});
});
and this is the client side code:
$(function() {
var FADE_TIME = 150; // ms
var TYPING_TIMER_LENGTH = 400; // ms
var COLORS = [
'#e21400', '#91580f', '#f8a700', '#f78b00',
'#58dc00', '#287b00', '#a8f07a', '#4ae8c4',
'#3b88eb', '#3824aa', '#a700ff', '#d300e7'
];
// Initialize variables
var $window = $(window);
var $usernameInput = $('.usernameInput'); // Input for username
var $messages = $('.messages'); // Messages area
var $inputMessage = $('.inputMessage'); // Input message input box
var $loginPage = $('.login.page'); // The login page
var $chatPage = $('.chat.page'); // The chatroom page
// Prompt for setting a username
var username;
var connected = false;
var typing = false;
var lastTypingTime;
var $currentInput = $usernameInput.focus();
var socket = io();
function addParticipantsMessage (data) {
var message = '';
if (data.numUsers === 1) {
message += "there's 1 participant";
} else {
message += "there are " + data.numUsers + " participants";
}
log(message);
}
// Sets the client's username
function setUsername () {
username = cleanInput($usernameInput.val().trim());
// If the username is valid
if (username) {
$loginPage.fadeOut();
$chatPage.show();
$loginPage.off('click');
$currentInput = $inputMessage.focus();
// Tell the server your username
socket.emit('add user', username);
}
}
// Sends a chat message
function sendMessage () {
var message = $inputMessage.val();
// Prevent markup from being injected into the message
message = cleanInput(message);
// if there is a non-empty message and a socket connection
if (message && connected) {
$inputMessage.val('');
addChatMessage({
username: username,
message: message
});
// tell server to execute 'new message' and send along one parameter
socket.emit('new message', message);
}
}
// Log a message
function log (message, options) {
var $el = $('<li>').addClass('log').text(message);
addMessageElement($el, options);
}
// Adds the visual chat message to the message list
function addChatMessage (data, options) {
// Don't fade the message in if there is an 'X was typing'
var $typingMessages = getTypingMessages(data);
options = options || {};
if ($typingMessages.length !== 0) {
options.fade = false;
$typingMessages.remove();
}
var $usernameDiv = $('<span class="username"/>')
.text(data.username)
.css('color', getUsernameColor(data.username));
var $messageBodyDiv = $('<span class="messageBody">')
.text(data.message);
var typingClass = data.typing ? 'typing' : '';
var $messageDiv = $('<li class="message"/>')
.data('username', data.username)
.addClass(typingClass)
.append($usernameDiv, $messageBodyDiv);
addMessageElement($messageDiv, options);
}
// Adds the visual chat typing message
function addChatTyping (data) {
data.typing = true;
data.message = 'is typing';
addChatMessage(data);
}
// Removes the visual chat typing message
function removeChatTyping (data) {
getTypingMessages(data).fadeOut(function () {
$(this).remove();
});
}
// Adds a message element to the messages and scrolls to the bottom
// el - The element to add as a message
// options.fade - If the element should fade-in (default = true)
// options.prepend - If the element should prepend
// all other messages (default = false)
function addMessageElement (el, options) {
var $el = $(el);
// Setup default options
if (!options) {
options = {};
}
if (typeof options.fade === 'undefined') {
options.fade = true;
}
if (typeof options.prepend === 'undefined') {
options.prepend = false;
}
// Apply options
if (options.fade) {
$el.hide().fadeIn(FADE_TIME);
}
if (options.prepend) {
$messages.prepend($el);
} else {
$messages.append($el);
}
$messages[0].scrollTop = $messages[0].scrollHeight;
}
// Prevents input from having injected markup
function cleanInput (input) {
return $('<div/>').text(input).text();
}
// Updates the typing event
function updateTyping () {
if (connected) {
if (!typing) {
typing = true;
socket.emit('typing');
}
lastTypingTime = (new Date()).getTime();
setTimeout(function () {
var typingTimer = (new Date()).getTime();
var timeDiff = typingTimer - lastTypingTime;
if (timeDiff >= TYPING_TIMER_LENGTH && typing) {
socket.emit('stop typing');
typing = false;
}
}, TYPING_TIMER_LENGTH);
}
}
// Gets the 'X is typing' messages of a user
function getTypingMessages (data) {
return $('.typing.message').filter(function (i) {
return $(this).data('username') === data.username;
});
}
// Gets the color of a username through our hash function
function getUsernameColor (username) {
// Compute hash code
var hash = 7;
for (var i = 0; i < username.length; i++) {
hash = username.charCodeAt(i) + (hash << 5) - hash;
}
// Calculate color
var index = Math.abs(hash % COLORS.length);
return COLORS[index];
}
// Keyboard events
$window.keydown(function (event) {
// Auto-focus the current input when a key is typed
if (!(event.ctrlKey || event.metaKey || event.altKey)) {
$currentInput.focus();
}
// When the client hits ENTER on their keyboard
if (event.which === 13) {
if (username) {
sendMessage();
socket.emit('stop typing');
typing = false;
} else {
setUsername();
}
}
});
$inputMessage.on('input', function() {
updateTyping();
});
// Click events
// Focus input when clicking anywhere on login page
$loginPage.click(function () {
$currentInput.focus();
});
// Focus input when clicking on the message input's border
$inputMessage.click(function () {
$inputMessage.focus();
});
// Socket events
// Whenever the server emits 'login', log the login message
socket.on('login', function (data) {
connected = true;
// Display the welcome message
var message = "Welcome to Socket.IO Chat – ";
log(message, {
prepend: true
});
addParticipantsMessage(data);
});
// Whenever the server emits 'new message', update the chat body
socket.on('new message', function (data) {
addChatMessage(data);
});
// Whenever the server emits 'user joined', log it in the chat body
socket.on('user joined', function (data) {
log(data.username + ' joined');
addParticipantsMessage(data);
});
// Whenever the server emits 'user left', log it in the chat body
socket.on('user left', function (data) {
log(data.username + ' left');
addParticipantsMessage(data);
removeChatTyping(data);
});
// Whenever the server emits 'typing', show the typing message
socket.on('typing', function (data) {
addChatTyping(data);
});
// Whenever the server emits 'stop typing', kill the typing message
socket.on('stop typing', function (data) {
removeChatTyping(data);
});
socket.on('disconnect', function () {
log('you have been disconnected');
});
socket.on('reconnect', function () {
log('you have been reconnected');
if (username) {
socket.emit('add user', username);
}
});
socket.on('reconnect_error', function () {
log('attempt to reconnect has failed');
});
});
I tried this Nginx configuration:
location /myapp/ {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header Host $http_host;
proxy_set_header X-NginX-Proxy true;
proxy_pass http://localhost:3000/;
proxy_redirect off;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
}
But im getting the following errors when i link to localhost/myapp:
http://localhost/socket.io/socket.io.js Failed to load resource: the server responded with a status of 404 (Not Found)
http://localhost/main.js Failed to load resource: the server responded with a status of 404 (Not Found)
Can someone please help me?

Answer 1

You have specified a location of /myapp/ in the nginx config but you haven't updated the html page to reference files at this location (http://localhost/myapp/*).