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  1. a89adf4 add the missing `setupTreeStatus` function by Tao Zhou · 5 weeks ago master
  2. 41bbb6c Fix tree-status text overflow issue by Josip Sokcevic · 3 months ago
  3. aa7b64b Replace @npm_bazel_rollup with @npm//@bazel/rollup by Tao Zhou · 3 months ago
  4. 0715f6c chumpdetector: Explicitly state chumping conditions in the warning by Tomasz Figa · 4 months ago
  5. b7360f1 Format Java files with google-java-format by David Pursehouse · 5 months ago

ChumpDetector Plugin for Gerrit

This plugin will allow developers to see the current status on their CLs. Status will be pulled from a configurable location. The Chromium project has many status sites such as:

The plugin will show users the status and will warn them in certain situations if they attempt to undertake actions that are contrary to the tree status.

The plugin does not provide enforcement - that is provided by other systems.


Before this plugin will work you'll need to configure it. You can do that by adding a new file to refs/meta/config for a Gerrit project. The configuration file should be called chumpdetector.config and should be of the form:

[project "some-interesting-project"]
  loginURL =
  viewURL =
  statusURL =
  withCredentials = false
  enforceCommitQueue = false
  disabledBranchPattern = ^(?:refs/meta/config|refs/heads/.*)$

Project name

The project name doesn‘t matter, it can be anything you’d like


If withCredentials is true and a request for status fails, the system assumes that a login is required and has not occurred. In that case the status message will change to “Login required. Click here to login.” The text will be a link that points to the value of loginURL. If loginURL is not set then the message will just be RequestError: Login required. with no link.


This should be the URL to your status app. This is used to provide a link that users can click on to take them to a new page that shows the full status.


This should be the URL to get a JSON blob of the current status. Usually this will be related to the viewURL value. This is the URL that will be queried via XHR periodically while the user is on the page to update the tree status.


This is simply passed through to the underlying JavaScript XMLHttpRequest object as the withCredentials parameter. You can read about it at


When true, this will show a modal warning to users if they try to submit the CL directly and warn them to use the CQ. This is Chromium concept, unless you have a Chromium-like CQ system. Just leave as false if you don't understand what any of those things mean.


CLs on branches that match this pattern will have the plugin disabled. This means they won‘t see tree status and tree status won’t effect the CL in any way.


This setting causes the plugin to request a URL via an an image that is dynamically added to the page before making any other fetch requests. This is useful in situations where the request to the status URL will fail without certain cookies being set for the status request domain. By using an image tag the browser will correctly follow any redirects that a login process may require in order to establish the session cookies.

Most installs will not need this configuration and can ignore it. For certain sites this may allow them to get security cookies before attempting status requests which will fail without the cookies.

To use with the local testsite

cd ~/gerrit
ln -s ~/chumpdetector ~/gerrit/plugins
bazel build //plugins/chumpdetector
cp -f ~/gerrit/bazel-bin/plugins/chumpdetector/chumpdetector.jar ~/gerrit_testsite/plugins/
bazel build gerrit
java -jar ~/gerrit/bazel-bin/gerrit.war init --batch --dev -d ~/gerrit_testsite
~/gerrit_testsite/bin/ start

When you make changes to chumpdetector

bazel build //plugins/chumpdetector
cp -f ~/gerrit/bazel-bin/plugins/chumpdetector/chumpdetector.jar ~/gerrit_testsite/plugins/
~/gerrit_testsite/bin/ restart

To use with the polygerrit-ui server against live data

mkdir -p polygerrit-ui/app/plugins/chumpdetector
ln -s /path/to/chumpdetector-plugin/src/main/resources/static polygerrit-ui/app/plugins/chumpdetector/static
./polygerrit-ui/ -host

You may also need to edit chumpdetectorURL to point directly at instead of being relative.