Add a custom linkification filter

Linkifiers make it easy to refer to issues or tickets in third party issue trackers, like GitHub, Salesforce, Zendesk, and others. For instance, you can add a filter that automatically turns #2468 into a link to https://github.com/zulip/zulip/issues/2468.

If the pattern appears in a message topic, Zulip adds a little button to the right of the topic that links to the appropriate URL.

Add a custom linkification filter

Understanding linkification patterns

This is best explained by example.

Hash followed by a number of any length.

• Pattern: #(?P<id>[0-9]+)
• URL format string: https://github.com/zulip/zulip/issues/%(id)s
• Original text: #2468
• Automatically links to: https://github.com/zulip/zulip/issues/2468

String of hexadecimal digits between 7 and 40 characters long.

• Pattern: (?P<id>[0-9a-f]{7,40})
• URL format string: https://github.com/zulip/zulip/commit/%(id)s
• Original text: abdc123
• Automatically links to: https://github.com/zulip/zulip/commit/abcd123

Generic GitHub org/repo#ID format:

• Pattern: (?P<org>[a-zA-Z0-9_-]+)/(?P<repo>[a-zA-Z0-9_-]+)#(?P<id>[0-9]+)
• URL format string: https://github.com/%(org)s/%(repo)s/issues/%(id)s
• Original text: zulip/zulip#2468
• Automatically links to: https://github.com/zulip/zulip/issues/2468

Linkifiers are implemented as a limited subset of Python 3 regular expressions, with validation designed to prevent common mistakes, avoid accidentally expensive linkifiers, and allow translation into equivalent JavaScript regular expressions for local echo.

If you have any trouble setting these up, please contact us with details on what you're trying to do, and we'll be happy to help you out.