Question

I’m currently learning node.js by developing a small chat application over TCP (classic case).

What I would like to do now is to extend this application to use static users:

• All logic around messaging should be based on users rather than
  sessions.
• Each session therefore needs to be saved along with a
  reference to the user (so that the application can send messages in
  the correct session based on user name).

• I have looked into Redis to store this data but not been successful so far.

          tcpServer.on 'connection', (tcpSocket) -> tcpSocket.write "Welcome"
          redis.hmset("sessions", userid, tcpSocket)
          tcpSocket.on "data", (data) ->
              redis.hvals "sessions", (err, repl) ->
                  repl.forEach (reply, y) ->
                      reply.Write("Data is written to clients!")
      tcpServer.listen 7000
  

Current error message: TypeError: Object [object Object] has no method ‘write’

This indicates that I cannot store a tcpSocket as I’m trying to do right now. Can someone tell me if I can make minor adjustments to make this right or should I rethinkt this solution?

Answer 1

Redis supports very few data types: string, lists, sets, sorted lists and hash tables. That’s it. Some other types, like Date, can be easily converted to/from string, so it can be used too. But socket is a complex internal object, so you most probably can’t convert it into string and therefore can’t store in Redis.