[question] Using Centrifugo-js in backend side (Websocket)

[sajjad-fatehi]

hi :)
we are using centrifugo-js in our back-end application for rpc, join/leave, publish , ...
but in peak times on our application our web-scoket connection from back-end to centrifugo server is disconnecting and reconnecting .

What does "reason" means ins this error message:
disconnect context : the reason is connection closed and reconnect is true

• Is it okay to use web-socket as a protocol to communicate with centrifugo (instead of API) ?
• How we can debug this issue (any suggestions) ?
• How can we determine the reason for closing the connection?

thank you

[FZambia]

Hello, using client SDK on the backend side may work - but it's not a scalable approach if you want to consume many channels and many messages. The idiomatic way to integrate with Centrifugo is outlined in the documentation. App users connect over real-time SDKs, backend uses server API to communicate with Centrifugo.

Trying to answer the questions:

what is the of this reason meaning ?

connection closed may be any network issue - it's actually a default reason when no other specific code received from the server in close handshake. Probably your connection is too slow and Centrifugo dropped it - in this case you may find this information in server debug logs and in disconnect code Prometheus metrics.

is it okay to use web-socket as a protocol to communicate with centrifugo (instead of API) ?

As said above - it may work for basic cases, but does not scale and may quickly become a bottleneck. Real-time SDKs exist for the application users with a reasonable message rate, not for the backend.

how we can debug this issue (any suggestions ) ?

You can try to find a reproducer, then isolate the root cause step by step. Think why the connection may be closed - it involves log inspection, understanding message volume. I'd start with server logs. If the connection is closed during "peak" hours as you mentioned - then it possibly can not keep up with the incoming message rate.

You can also take centrifuge-js and try to log WebSocket transport close code - https://github.com/centrifugal/centrifuge-js/blob/047301dc7368c62ee34e0d8be0f3a3e638eb3598/src/centrifuge.ts#L801, we are not exposing it in the SDK API directly - probably it will contain something useful which will point you to some problem.

[sajjad-fatehi]

thanks a lot 😍