/flask-sse

Server-Sent Events for Flask

Primary LanguagePythonMIT LicenseMIT

Flask SSE Build status Test coverage Documentation

A Flask extension for HTML5 server-sent events support, powered by Redis.

Example of sending events:

from flask import Flask
from flask_sse import sse

app = Flask(__name__)
app.config["REDIS_URL"] = "redis://localhost"
app.register_blueprint(sse, url_prefix='/stream')

@app.route('/send')
def send_message():
    sse.publish({"message": "Hello!"}, type='greeting')
    return "Message sent!"

To receive events on a webpage, use Javascript to connect to the event stream, like this:

var source = new EventSource("{{ url_for('sse.stream') }}");
source.addEventListener('greeting', function(event) {
    var data = JSON.parse(event.data);
    // do what you want with this data
}, false);

The full documentation for this project is hosted on ReadTheDocs.