🌿 Bazel for beginners

Getting started with Bazel for absolute beginners

About Bazel

• Bazel is a tool to build and test software at any scale
• It's extremely fast and makes builds reproducible
• It's able to build any language
• It's used by many big companies

Bazel Basics

• The WORKSPACE file marks the root of a Bazel workspace
• BUILD files mark a directory as a package
• Build targets are defined insideBUILD files
• Targets are defined by rules
• Rules are written in Starlark (But most end users won't rules themselves)

Usage

Installation

• Install Bazelisk to manage different version of Bazel
  • With NPM: npm i -g @bazel/bazelisk (requires Node.js)
  • On macOS: brew install bazelisk

Commands

• bazel version (Get version of Bazel)
• bazel build //... (Build everything)
• bazel clean (Clean Bazel outputs)
• bazel build //files/... (Build everything inside the files package)
• bazel build //:bazel_slogan (Only build the bazel_slogan target)
• bazel test //... (Test everything)
• bazel query ... (List all targets)
• bazel query --noimplicit_deps 'deps(:bazel_slogan_test)' --output graph | dot -Tpng > graph.png (Generate a graph dependency graph of the :bazel_slogan_test target)

💡 You can also omit the //

Development Environment

• Install the official Bazel extensions
• Install Buildifier for formatting
  • With NPM: npm i -g @bazel/buildifier (requires Node.js)
  • On macOS: brew install buildifier