commit	943c5b65f0642043a2d6847151dbbb82eebba738	[log] [tgz]
author	Jacek Centkowski <geminica.programs@gmail.com>	Sat Apr 15 15:01:03 2023 +0200
committer	Jacek Centkowski <geminica.programs@gmail.com>	Fri May 26 10:47:35 2023 +0200
tree	fb764b8d4393df775d017b2819f59ff2b47c052c
parent	69f0c5a445cfcd874d0289b282a6607c4c84a1b9 [diff]

Cache the OWNERS file's parsed content

The OWNERS file is rarely modified however it is being read and parsed
for every single change that gets evaluated. Introduce the cache (called
`owners-path_owners_entries`) that holds the PathOwnersEntry value for a
project, branch and path (typically `refs/meta/config`, development
branch and path). The path is especially important for projects with
deep directories structure (mono-repos) and cache size should be
carefully adjusted to adhere to it (1 dir level = 1 cache entry).

It gets invalidated when project's ref is updated.
As a result it reduces 2-3 times the configuration load latency which is
reflected in performance of prolog and submit requirements.

There are several constraints that influenced the implementation
* the `PathOwners` is a common class used by both owners and
  owners-autoassign plugins
* the `PathOwners`, in the owners plugin prolog's engine, is
  instantiated by the constructor call and injection is not possible
  there

The config.md was updated with the cache configuration.

Bug: Issue 16830
Change-Id: Ic7d61de07f3ec5169f0cf7c4ae8266351543e108

17 files changed

tree: fb764b8d4393df775d017b2819f59ff2b47c052c

README.md

Gerrit OWNERS Plugin

This plugin provides some Prolog predicates that can be used to add customized validation checks based on the approval of ‘path owners’ of a particular folder in the project.

That allows creating a single big project including multiple components and users have different roles depending on the particular path where changes are being proposed. A user can be “owner” in a specific directory, and thus influencing the approvals of changes there, but cannot do the same in others paths, so assuring a kind of dynamic subproject access rights.

How it works

There are currently two main prolog public verbs:

add_owner_approval/3 (UserList, InList, OutList) appends label('Owner-Approval', need(_)) to InList building OutList if UserList has no users contained in the defined owners of this path change.

In other words, the predicate just copies InList to OutList if at least one of the elements in UserList is an owner.

add_owner_approval/2 (InList, OutList) appends label('Owner-Approval', need(_)) to InList building OutList if no owners has given a Code-Review +2 to this path change.

This predicate is similar to the first one but generates a UserList with an hardcoded policy.

Since add_owner_approval/3 is not using hard coded policies, it can be suitable for complex customizations.

Auto assigner

There is a second plugin, gerrit-owners-autoassign which depends on gerrit-owners. It will automatically assign all of the owners to review a change when it's created or updated.

How to build

This plugin is built with Bazel and two build modes are supported:

Standalone
In Gerrit tree

Build standalone

To build the plugin, issue the following command:

  bazel build :all

The output is created in

  bazel-bin/owners/owners.jar
  bazel-bin/owners-autoassign/owners-autoassign.jar
  bazel-bin/owners-api/owners-api.jar

To execute the tests run:

  bazel test //...

This project can be imported into the Eclipse IDE:

  ./tools/eclipse/project.sh

Build in Gerrit tree

Create symbolic links of the owners and owners-autoassign folders and of the external_plugin_deps.bzl file to the Gerrit source code /plugins directory.

Create a symbolic link of the owners-common plugin to the Gerrit source code directory.

Then build the owners and owners-autoassign plugins with the usual Gerrit plugin compile command.

Example:

   $ git clone https://gerrit.googlesource.com/plugins/owners
   $ git clone https://gerrit.googlesource.com/gerrit
   $ cd gerrit/plugins
   $ ln -s ../../owners/owners .
   $ ln -s ../../owners/owners-autoassign .
   $ ln -s ../../owners/owners-api .
   $ ln -sf ../../owners/external_plugin_deps.bzl .
   $ cd ..
   $ ln -s ../owners/owners-common .
   $ bazel build plugins/owners plugins/owners-autoassign

NOTE: the owners-common folder is producing shared artifacts for the two plugins and does not need to be built separately being a direct dependency of the build process. Its resulting .jar must not be installed in gerrit plugins directory.

The output is created in

  bazel-bin/plugins/owners/owners.jar
  bazel-bin/plugins/owners-autoassign/owners-autoassign.jar

To execute the tests run:

  bazel test owners-common:test

This project can be imported into the Eclipse IDE:

Add the plugin name to the CUSTOM_PLUGINS (and in case when you want to run tests from the IDE to CUSTOM_PLUGINS_TEST_DEPS) in Gerrit core in tools/bzl/plugins.bzl file and run:

  ./tools/eclipse/project.py