# Gerrit Code Review - Building plugins

version v2.10.2-23-g039a170

From build process perspective there are three types of plugins:

- Maven driven

- Buck in tree driven

- Buck standalone driven

These types can be combined: if both files in plugin’s root directory exist:

- `BUCK`

- `pom.xml`

the plugin can be built with both Buck and Maven.

## Maven driven build

If plugin contains `pom.xml` file, it can be built with Maven as usually:

    mvn clean package

Exceptions from the rule above:

### Exception 1:

Plugin’s `pom.xml` references snapshot version of plugin API: `2.8-SNAPSHOT`. In this case there are two possibilities:

- switch to release API. Change plugin API version in `pom.xml` from `2.8-SNAPSHOT` to `2.8.1` and repeat step 1 above.

- build and install `SNAPSHOT` version of plugin API in local Maven repository:

    buck build api_install

### Exception 2:

Plugin’s `pom.xml` references other own or foreign (unpublished) libraries or even other Gerrit plugins. These libraries and/or plugins must be built and installed in local Maven repository. Clone the related projects and issue

    mvn install

Repeat step 1. above.

## Buck in tree driven

The fact that plugin contains `BUCK` file doesn’t mean that building this plugin from the plugin directory works. For now it doesn’t. Buck in tree driven means it can only be built from within Gerrit tree. Clone or link the plugin into gerrit/plugins directory:

    cd gerrit
    buck build plugins/<plugin-name>:<plugin-name>

The output can be normally found in the following directory:

    buck-out/gen/plugins/<plugin-name>/<plugin-name>.jar

Some plugins describe their build process in `src/main/resources/Documentation/build.md` file. It may worth checking.

## Buck standalone driven

Only few plugins support that mode for now:

    cd reviewers
    buck build plugin

Part of Gerrit Code Review