wsnotifier is a lightweight gevent based asynchronous websocket server written in Python. wsnotifier exposes HTTP APIs for forwarding the messages to the websocket clients. This makes it easier to use the service with any web application. It's completely written in Python and doesn't depend on external systems like Redis for storing/retrieving messages.

You can install using pip

$ pip install git+https://github.com/semk/wsnotifier.git

Or using docker

$ docker pull semk/wsnotifier

$ wsnotifier
Starting wsnotifier on ws://0.0.0.0:1729/alerts and http://0.0.0.0:1729/alerts

Or using docker

$ docker run -p 1729:1729 --rm -it semk/wsnotifier
Starting wsnotifier on ws://0.0.0.0:1729/alerts and http://0.0.0.0:1729/alerts

wscat is a nice commandline websocket client. You can install it by

$ npm install -g wscat

Connect to the websocket server at ws://0.0.0.0:1729/alerts

$ wscat -c ws://localhost:1729/alerts
connected (press CTRL+C to quit)

You can use any HTTP client to send the messages. This will be forwarded to all the connected websocket clients asynchronously. A Python client for wsnotifier is available here

$ curl -X POST -H "Content-Type: application/json" -d '{"id": "unique-message-id", "type": "important", "message": "important message"}' http://0.0.0.0:1729/alerts
{"status": "success"}

You can see the forwarded message appearing on the wscat client instantly.

$ wscat -c ws://localhost:1729/alerts
connected (press CTRL+C to quit)
< {"message": "important message", "type": "important", "id": "unique-message-id"}
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