Bazel BSP

An implementation of the Build Server Protocol for Bazel.

Status

Below is a list of languages supported over Bazel BSP and their implementation status.

• Language: name of the Language
• Import: Ability to import a project's targets, sources, dependencies, and resources.
• Compilation: Ability to compile
• Run: Ability to run
• Test: Ability to test

Language	Import	Compilation	Run	Test	Diagnostics
Scala	✅	✅	✅	✅	✅
Java	✅	✅	✅	✅	✅
Kotlin	✅	✅	✅	✅	✅

Installation

Easy way (coursier)

1. Have coursier installed
2. Run in the directory where Bazel BSP should be installed:

cs launch org.jetbrains.bsp:bazel-bsp:2.7.2 -M org.jetbrains.bsp.bazel.install.Install

3. Add bsp generated folders to your .gitignore: .bsp and .bazelbsp

More difficult way (from sources)

Might be useful during development

Using install script

1. Be inside this project
2. Run ./install.sh <installer flags> (--help is available)

Using coursier

1. Have coursier installed
2. Be inside this project
3. Change the project version - maven_coordinates attribute in the server/src/main/java/org/jetbrains/bsp/bazel/BUILD file
4. Publish a new version:

bazel run --stamp --define "maven_repo=file://$HOME/.m2/repository" //server/src/main/java/org/jetbrains/bsp/bazel:bsp.publish

7. Enter directory where Bazel BSP should be installed
8. Install your version:

cs launch -r m2Local org.jetbrains.bsp:bazel-bsp:<your version> -M org.jetbrains.bsp.bazel.install.Install

Using Bloop (deprecated!)

By default Bazel BSP runs as a BSP server and invokes Bazel to compile, test and run targets. This provides the most accurate build results at the expense of
compile/test/run latency. Bazel BSP can optionally be configured to use Bloop as the BSP server instead. Bloop provides a much lower latency with the trade-off that the Bloop model may not perfectly represent the Bazel configuration.

Installing with Bloop

The instructions above will work in Bloop mode as well, simply pass --use_bloop as an installation option. However, when using Bloop mode Bazel BSP can also install itself outside the source root directory. This can be useful in large shared repositories where it's undesirable to keep the Bazel BSP projects inside the repository itself.

In the examples below, we'll use ~/src/my-repo as the "repository root" and ~/bazel-bsp-projects as the "Bazel BSP project root", however both can be any directory.

To install Bazel BSP outside the repository root:

1. Change directories into the repository root: cd ~/src/my-repo
2. Invoke the Bazel BSP installer as described above (via Coursier or run the installer JAR directly), passing in:
   1. --use-bloop
   2. -d ~/bazel-bsp-projects/my-repo-project

For example, using Coursier:

cd ~/src/my-repository
cs launch org.jetbrains.bsp:bazel-bsp:2.7.2 -M org.jetbrains.bsp.bazel.install.Install \
  -- \
  --use-bloop \
  -t //my-targets/... \
  -d ~/bazel-bsp-projects/my-targets-project 

This will create a set of BSP and Bloop projects in ~/bazel-bsp-projects/my-targets-project which can then be opened in IntelliJ or any other IDE that supports BSP.

Project Views

In order to work on huge monorepos you might want to specify directories and targets to work on. To address this issue, Bazel BSP supports (partly) the Project Views introduced by Google.

Check project view readme for more info.

Tests

End-to-end tests

e2e directory contains end-2-end tests that check various scenarios of server usage.

• bazel run //e2e:all - to run all tests
• bazel run //e2e:<specific test> - to run a specific test (to see all possible tests, check the e2e/BUILD file)

Unit tests

Most modules also have unit tests that can be run using bazel test //<module>/... or just bazel test //... to run all tests in the project.

Contributing

Want to contribute? Great! Follow these rules.