Regular Expression Subscriptions

Regular Expression (Regex) subscriptions allow a regular expression to be supplied in the place of a topic name. When you supply a regular expression, it is as if a subscription is made to every topic that matches your expression, including topics that do not yet exist at the time of creating the subscription.

To use a regular expression, simply supply the regular expression in place of the topic name in the subscribe() call. For example:

def message_handler(msg):
    topic = msg.get_topic()

subscription_id = client.subscribe(
    message_handler,
    "orders.*"
)

In this example, messages on topics orders-north-america, orders-europe, and new-orders would match the regular expression. Messages published to any of those topics will be sent to our message_handler function. As in the example, you can use the get_topic() method to determine the actual topic of the message sent to the function.