Bazel Testcontainers

This repository is just a proof of concept of a Java application what uses Testcontainers for testing.

In this PoC we will:

1. Test if we can build and test a Bazel project locally using Testcontainers
   • ✅ Build
   • ✅ Test
2. Test if we can build and test a Bazel project remotely using Testcontainers and Bazel RBE (Remote Build Execution) in Google Cloud RBE.
   • ✅ Build
   • ✅ Test

This repository takes as an example the redis-backed-cache from the offical java testcontainers examples.

What is Bazel?

Bazel is a build system, just like Make or Gradle.

Some of it features:

• Suitable for almost every programming language.
• Suitable for large monorepos
• Scalable
• Speeds up building and testing

Some of Bazel's features include Remote Build Execution. With RBE we can spread our builds and tests within a large and remote build farm. This way we can speed up even more our builds and tests.

Learn more about Bazel at https://bazel.build/ and chech remote execution overview.

What are Testcontainers?

With Testcontainers you can manage programatically environment dependencies needed for running your integration or acceptance tests. For example, you need a running database, a Kafka Cluster or a Browser to run UI tests. Testcontainers is available for multiple languages (Java, Go, Python...). Your only requisite will be to have a running Docker API endpoint (Unix Socket or TCP).

In this repository we will see how can we combine Bazel and Testcontainers.

Executing Bazel

1. Locally

Build

To build locally using Bazel:

bazel build //...

Expected output:

INFO: Analyzed 3 targets (31 packages loaded, 702 targets configured).
INFO: Found 3 targets...
INFO: Deleting stale sandbox base /private/var/tmp/_bazel_pablo.moncada/f30eaa7669672642f9999e4ad8e660c0/sandbox
INFO: Elapsed time: 5.751s, Critical Path: 0.38s
INFO: 0 processes.
INFO: Build completed successfully, 1 total action

Test

To test locally using Bazel:

bazel test //...

Expected output:

INFO: Analyzed 3 targets (0 packages loaded, 0 targets configured).
INFO: Found 2 targets and 1 test target...
INFO: Elapsed time: 0.273s, Critical Path: 0.02s
INFO: 0 processes.
INFO: Build completed successfully, 1 total action
//src/test/java:RedisBackedCacheTest                             PASSED in 19.3s

Executed 0 out of 1 test: 1 test passes.
INFO: Build completed successfully, 1 total action

2. Remotely

To execute a build remotely using Google RBE you will need to have access to the private alpha. You can request access by filling this form.

You can also use self-hosted solutions:

• Buildbarn
• Buildfarm

Build

To build remotely using Bazel:

bazel build //... --config=remote --remote_instance_name=projects/$GCP_PROJECT_ID/instances/$RBE_INSTANCE

Expected output:

INFO: Analyzed 13 targets (1 packages loaded, 126 targets configured).
INFO: Found 13 targets...
INFO: Elapsed time: 67.431s, Critical Path: 66.28s
INFO: 66 processes: 1 remote cache hit, 65 remote.
INFO: Build completed successfully, 117 total actions

Test

To test remotely using Bazel:

bazel test //... --config=remote --remote_instance_name=projects/$GCP_PROJECT_ID/instances/$RBE_INSTANCE

Expected output:

INFO: Analyzed 3 targets (0 packages loaded, 0 targets configured).
INFO: Found 2 targets and 1 test target...
INFO: Elapsed time: 1.237s, Critical Path: 0.01s
INFO: 0 processes.
INFO: Build completed successfully, 1 total action
//src/test/java:RedisBackedCacheTest                            (cached) PASSED in 28.3s

Executed 0 out of 1 test: 1 test passes.
INFO: Build completed successfully, 1 total action