2019-09-08
2436
#node
Fernando Doglio
5657
Sep 8, 2019 ⋅ 8 min read

Writing a working chat server in Node

Fernando Doglio Technical Manager at Globant. Author of books and maker of software things. Find me online at fdoglio.com.

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3 Replies to "Writing a working chat server in Node"

  1. This is a nice breakdown of Socket chat servers. I’m currently doing something similar on a personal project. I also have events emitted when a user sends a friend request, accepts the request, etc.

    Do you recommend storing that Socket instance to user ID map in a service like Redis? I’m thinking of ways to scale up my current implementation.

  2. Hey O. Okeh, thanks for reading!
    In regards to your question, it depends. If what you’re looking for is scaling up to accommodate more users, you need more instances running. +
    I’m assuming you’ve created a dedicated chat service, which you should be able to clone.Then storing session information in Redis will help you more than storing the socket instance-user id map, because that way, your services can remain stateless, and clients can connect to any copy of your service (and any service will have access to the shared memory that Redis represents) without without losing session data.

    So my recommendation would be to use Redis as a shared memory if that is what you need, and keep cloning your chat services with a possible load balancer in front of them.

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