小开

最佳答案

OLD only use a reference

Dependencies

uses express, socket.io, node_redis and last but not least the sample code from media fire.

Install node.js+npm(as non root)

First you should(if you have not done this yet) install node.js+npm in 30 seconds (the right way because you should NOT run npm as root):

echo 'export PATH=$HOME/local/bin:$PATH' >> ~/.bashrc
. ~/.bashrc
mkdir ~/local
mkdir ~/node-latest-install
cd ~/node-latest-install
curl http://nodejs.org/dist/node-latest.tar.gz | tar xz --strip-components=1
./configure --prefix=~/local
make install # ok, fine, this step probably takes more than 30 seconds...
curl http://npmjs.org/install.sh | sh

Install dependencies

After you installed node+npm you should install dependencies by issuing:

npm install express
npm install socket.io
npm install hiredis redis # hiredis to use c binding for redis => FAST :)

Download sample

You can download complete sample from mediafire.

Unzip package

unzip pbsb.zip # can also do via graphical interface if you prefer.

What's inside zip

./app.js

const PORT = 3000;
const HOST = 'localhost';


var express = require('express');


var app = module.exports = express.createServer();


app.use(express.staticProvider(__dirname + '/public'));


const redis = require('redis');
const client = redis.createClient();


const io = require('socket.io');


if (!module.parent) {
app.listen(PORT, HOST);
console.log("Express server listening on port %d", app.address().port)


const socket  = io.listen(app);


socket.on('connection', function(client) {
const subscribe = redis.createClient();
subscribe.subscribe('pubsub'); //    listen to messages from channel pubsub


subscribe.on("message", function(channel, message) {
client.send(message);
});


client.on('message', function(msg) {
});


client.on('disconnect', function() {
subscribe.quit();
});
});
}

./public/index.html

<html>
<head>
<title>PubSub</title>
<script src="/socket.io/socket.io.js"></script>
<script src="/javascripts/jquery-1.4.3.min.js"></script>
</head>
<body>
<div id="content"></div>
<script>
$(document).ready(function() {
var socket = new io.Socket('localhost', {port: 3000, rememberTransport: false/*, transports: ['xhr-polling']*/});
var content = $('#content');


socket.on('connect', function() {
});


socket.on('message', function(message){
content.prepend(message + '<br />');
}) ;


socket.on('disconnect', function() {
console.log('disconnected');
content.html("<b>Disconnected!</b>");
});


socket.connect();
});
</script>
</body>
</html>

Start server

cd pbsb
node app.js

Start browser

Best if you start google chrome(because of websockets support, but not necessary). Visit http://localhost:3000 to see sample(in the beginning you don't see anything but PubSub as title).

But on publish to channel pubsub you should see a message. Below we publish "Hello world!" to the browser.

From ./redis-cli

publish pubsub "Hello world!"

小开

Handle redis errors to stop nodejs from exiting. You can do this by writing;

subcribe.on("error", function(){
//Deal with error
})

I think you get the exception because you are using the same client which is subscribed to publish messages. Create a separate client for publishing messages and that could solve your problem.

小开

Update to the code:

staticProvider

now renamed to

static

see migration guide

小开

Check out acani-node on GitHub, especially the file acani-node-server.js. If these links are broken, look for acani-chat-server among acani's GitHub public repositories.

小开

according to @alex solution. if you have an error like this one as per @tyler mention:

node.js:134
throw e; // process.nextTick error, or 'error'


event on first tick ^ Error: Redis connection to 127.0.0.1:6379 failed - ECONNREFUSED, Connection refused at Socket.

then you need to install Redis first. check this out:

http://redis.io/download

小开

If you want to get this working with socket.io 0.7 AND an external webserver you need to change (besides the staticProvider -> static issue):

a) provide the domain name instead of localhost (i.e. var socket = io.connect('http://my.domain.com:3000'); ) in the index.html

b) change HOST in app.js (i.e. const HOST = 'my.domain.com'; )

c) and add sockets in line 37 of app.js (i.e. 'socket.sockets.on('connection', function(client) { …' )

小开

here's a simplified example without as many dependencies. You do still need to npm install hiredis redis

The node JavaScript:

var redis = require("redis"),
client = redis.createClient();


client.subscribe("pubsub");
client.on("message", function(channel, message){
console.log(channel + ": " + message);
});

...put that in a pubsub.js file and run node pubsub.js

in redis-cli:

redis> publish pubsub "Hello Wonky!"
(integer) 1

which should display: pubsub: Hello Wonky! in the terminal running node! Congrats!

Additional 4/23/2013: I also want to make note that when a client subscribes to a pub/sub channel it goes into subscriber mode and is limited to subscriber commands. You'll just need to create additional instances of redis clients. client1 = redis.createClient(), client2 = redis.createClient() so one can be in subscriber mode and the other can issue regular DB commands.

小开

Complete Redis Pub/Sub Example (Real-time Chat using Hapi.js & Socket.io)

We were trying to understand Redis Publish/Subscribe ("Pub/Sub") and all the existing examples were either outdated, too simple or had no tests. So we wrote a Complete Real-time Chat using Hapi.js + Socket.io + Redis Pub/Sub Example with End-to-End Tests!

https://github.com/dwyl/hapi-socketio-redis-chat-example

The Pub/Sub component is only a few lines of node.js code: https://github.com/dwyl/hapi-socketio-redis-chat-example/blob/master/lib/chat.js#L33-L40

Rather than pasting it here (without any context) we encourage you to checkout/try the example.

We built it using Hapi.js but the chat.js file is de-coupled from Hapi and can easily be used with a basic node.js http server or express (etc.)

如何使用 rediesPUBLISH/SUBSCRIBE 与 nodejs 通知客户端当数据值发生变化？