socketio与redis和haproxy进行服务器间通信

Question

I'm working on a project which uses SocketIO and should be Horizontally scalable. Im using

• A Load Balancer using HAProxy
• Multiple Node Servers (2-4)
• Database server(Redis and MongoDB)

I'm able to redirect my incoming Socket connections to Node servers using roundrobin method. Socket connection is stable and if I use socket.emit() I'm receiving the data. I'm also able to emit to the Other socket connection connected to the same Node server.

I'm facing issue in the following scenario:

User A connected to Node server 1 and User B connected to Node Server 2

My intention is to store the Socket data in redis

If User A wants to send some data to User B, how can I tell the Node server 2 to emit the data to User B from Node server 1

Please let me know how can I achieve this (with ref if possible).

Thanks in advance.

Answer 1

This scenario is a match for the case Pub/Sub of Redis .

If you haven't already, you should try Pub/Sub .

Answer 2

Have a look at socket.io Redis adapter . It should be exactly what you need.

clients() method in particular looks promising. Keep in mind, that socket.io creates a unique room for each client.