Monorail Issue Tracker

What is Monorail?

Monorail is the issue tracker used by Chromium-related projects on https://bugs.chromium.org.

Monorail is a port of the Google Code issue tracker to AppEngine. It provides continuity for the chrome team with the least number of unknowns, while achieving these goals:
- Vastly simpler to develop and operate:
- Runs on Google App Engine, data in Google Cloud SQL and GCS.
- Built on simpler GAE APIs.
- Pure python, greatly simplified code, supported by Chrome Operations team.
Better product focus:
- Focused on needs of larger teams: e.g., built-in support for user groups, custom fields, more control over issue visibility, better validation to improve issue data quality.
- Closely aligned with the chrome development process and dedicated to the future needs of the chrome team.
Scaleable by design:
- Designed from the start to handle Chrome's future issue tracking needs.
- Efficient implementation of queries like issue ID and date ranges.
- Improved security and spam defenses.
Ease of transition:
- Same data model as used by our existing issues for an exact import.
- Our v1 API is very close to the old Google Code API.
- Same ACLs and project administration controls.
- Familiar UI, but streamlined. One-to-one redirects from Google Code.

Developed as open source.
Flexible issue representation that allows for creation of one-off labels.
Custom fields defined by project owners.
Support for components. Issues can be in multiple components.
Filter rules are IF-THEN rules that automatically add labels or CC users.
Fine-grained permission system allows control over visiblity and individual actions on individual issues.
Saved queries per user and per project.
Users can subscribe to their saved queries (not just labels) and get mail on updates.
User groups are built into Monorail, so no update lag on built-in groups. We can also sync from Google Groups.
Support for custom fields that are treated very much like built-in fields. Custom fields can be multi-valued.
User-valued custom fields can be restricted to only allow qualified users that have a given permission.
User-valued custom fields can trigger notifications to those users, and/or grant permissions to the named users.
Notification emails include detailed footers that give an ordered list of the reasons why the email was sent to you, with specifics such as “You are the on the auto-cc list of Component C”.
ML-based spam detection applied before notifications are generated. Users can also flag spam.
Limited-availability Endpoints API that works like the old Google Code API.
Personal hotlists with ranked issues.