Real-time events API
Zulip's real-time events API lets you write software that reacts
immediately to events happening in Zulip. This API is what powers the
real-time updates in the Zulip web and mobile apps. As a result, the
events available via this API cover all changes to data displayed in
the Zulip product, from new messages to stream descriptions to
emoji reactions to changes in user or organization-level settings.
Using the events API
The simplest way to use Zulip's real-time events API is by using
call_on_each_event from our Python bindings. You just need to write
a Python function (in the examples below, the lambdas) and pass it
into call_on_each_event; your function will be called whenever a new
event matching the specific event_type and/or narrow parameters
occurs in Zulip.
call_on_each_event takes care of all the potentially tricky details
of long-polling, error handling, exponential backoff in retries, etc.
It's cousin, call_on_each_message, provides an even simpler
interface for processing Zulip messages.
More complex applications (like a Zulip terminal client) may need to
instead use the raw register and
events endpoints.
Usage examples
#!/usr/bin/env python
import sys
import zulip
# Pass the path to your zuliprc file here.
client = zulip.Client(config_file="~/zuliprc")
# Print every message the current user would receive
# This is a blocking call that will run forever
client.call_on_each_message(lambda msg: sys.stdout.write(str(msg) + "\n"))
# Print every event relevant to the user
# This is a blocking call that will run forever
client.call_on_each_event(lambda event: sys.stdout.write(str(event) + "\n"))
Parameters
You may also pass in the following keyword arguments to call_on_each_event:
narrow optional
Example: [["stream", "Denmark"]]
A JSON-encoded array of arrays of length 2 indicating the
narrow for which you'd like to receive events for. For
instance, to receive events for the stream Denmark, you
would specify narrow=[['stream', 'Denmark']]. Another
example is narrow=[['is', 'private']] for private messages.
Default is [].
event_types optional
Example: ["message"]
A JSON-encoded array indicating which types of events you're interested
in. Values that you might find useful include:
- message (messages)
- subscription (changes in your subscriptions)
- realm_user (changes to users in the organization and
their properties, such as their name).
If you do not specify this parameter, you will receive all
events, and have to filter out the events not relevant to
your client in your client code. For most applications, one
is only interested in messages, so one specifies:
event_types=['message']
See the GET /events documentation for
more details on the format of individual events.