Push messages to clients in Python

Question

How can I implement a system that can "push" messages to clients when necessary? Basically, what I need is the ability to "push" text to Python clients from a Python server. The text will then be parsed to actions that will take care at the client side (I already know how to do this thing, once an 'action-text' is received). I can check every couple of seconds for new 'action-texts' that are waiting -- it's just I don't think it's reliable and scalable to thousands of clients. The real-time thing is very important here.

Any suggestions, please?

Answer 1

You can use redis publish subscribe model more here.

Redis is highly scalable and fast.

Example: (From https://github.com/andymccurdy/redis-py/blob/master/tests/pubsub.py)

import redis
import unittest

class PubSubTestCase(unittest.TestCase):
    def setUp(self):
        self.connection_pool = redis.ConnectionPool()
        self.client = redis.Redis(connection_pool=self.connection_pool)
        self.pubsub = self.client.pubsub()

    def tearDown(self):
        self.connection_pool.disconnect()

    def test_channel_subscribe(self):
        self.assertEquals(
            self.pubsub.subscribe('foo'),
            ['subscribe', 'foo', 1]
            )
        self.assertEquals(self.client.publish('foo', 'hello foo'), 1)
        self.assertEquals(
            self.pubsub.listen().next(),
            {
                'type': 'message',
                'pattern': None,
                'channel': 'foo',
                'data': 'hello foo'
            }
            )
        self.assertEquals(
            self.pubsub.unsubscribe('foo'),
            ['unsubscribe', 'foo', 0]
            )

    def test_pattern_subscribe(self):
        self.assertEquals(
            self.pubsub.psubscribe('fo*'),
            ['psubscribe', 'fo*', 1]
            )
        self.assertEquals(self.client.publish('foo', 'hello foo'), 1)
        self.assertEquals(
            self.pubsub.listen().next(),
            {
                'type': 'pmessage',
                'pattern': 'fo*',
                'channel': 'foo',
                'data': 'hello foo'
            }
            )
        self.assertEquals(
            self.pubsub.punsubscribe('fo*'),
            ['punsubscribe', 'fo*', 0]
            )