Writing a new integration

Integrations are one of the most important parts of a group chat tool like Zulip, and we are committed to making integrating with Zulip and getting your integration merged upstream so that everyone else can benefit from it, as easy as possible while maintaining the high quality of the Zulip integrations library.

On this page you'll find:

A detailed walkthrough of a simple "Hello World" integration can be found in the incoming webhook walkthrough.

Contributions to this guide are very welcome, so if you run into any issues following these instructions or come up with any tips or tools that help writing integration, please email zulip-devel@googlegroups.com, open an issue, or submit a pull request to share your ideas!

Types of integrations

We have several different ways that we integrate with 3rd party products, ordered here by which types we prefer to write:

  1. Incoming webhook integrations (examples: Freshdesk, GitHub), where the third-party service supports posting content to a particular URI on our site with data about the event. For these, you usually just need to create a new python package in the zerver/webhooks/ directory. You can easily find recent commits adding new integrations to crib from via git log zerver/webhooks/.

  2. Python script integrations (examples: SVN, Git), where we can get the service to call our integration (by shelling out or otherwise), passing in the required data. Our preferred model for these is to ship these integrations in the Zulip Python API distribution, within the integrations directory there.

  3. Plugin integrations (examples: Jenkins, Hubot, Trac) where the user needs to install a plugin into their existing software. These are often more work, but for some products are the only way to integrate with the product at all.

General advice

  • Consider using our Zulip markup to make the output from your integration especially attractive or useful (e.g. emoji, markdown emphasis, @-mentions, or !avatar(email)).

  • Use topics effectively to ensure sequential messages about the same thing are threaded together; this makes for much better consumption by users. E.g. for a bug tracker integration, put the bug number in the topic for all messages; for an integration like Nagios, put the service in the topic.

  • Integrations that don't match a team's workflow can often be uselessly spammy. Give careful thought to providing options for triggering Zulip messages only for certain message types, certain projects, or sending different messages to different streams/topics, to make it easy for teams to configure the integration to support their workflow.

  • Consistently capitalize the name of the integration in the documentation and the Client name the way the vendor does. It's OK to use all-lower-case in the implementation.

  • Sometimes it can be helpful to contact the vendor if it appears they don't have an API or webhook we can use -- sometimes the right API is just not properly documented.

  • A helpful tool for testing your integration is UltraHook, which allows you to receive webhook calls via your local Zulip development environment. This enables you to do end-to-end testing with live data from the service you're integrating and can help you spot why something isn't working or if the service is using custom HTTP headers.

Python script and plugin integrations

For plugin integrations, usually you will need to consult the documentation for the third party software in order to learn how to write the integration. But we have a few notes on how to do these:

  • You should always send messages by POSTing to URLs of the form https://zulip.example.com/v1/messages/.

  • We usually build Python script integration with (at least) 2 files: zulip_foo_config.py containing the configuration for the integration including the bots' API keys, plus a script that reads from this configuration to actually do the work (that way, it's possible to update the script without breaking users' configurations).

  • Be sure to test your integration carefully and document how to install it (see notes on documentation below).

  • You should specify a clear HTTP User-Agent for your integration. The user agent should at a minimum identify the integration and version number, separated by a slash. If possible, you should collect platform information and include that in ()s after the version number. Some examples of ideal UAs are:

ZulipDesktop/0.7.0 (Ubuntu; 14.04)
ZulipJenkins/0.1.0 (Windows; 7.2)
ZulipMobile/0.5.4 (Android; 4.2; maguro)