Aspect's Bazel helpers library

Base Starlark libraries and basic Bazel rules which are useful for constructing rulesets and BUILD files.

This module depends on bazel-skylib. In theory all these utilities could be upstreamed to bazel-skylib, but the declared scope of that project is narrow and it‘s very difficult to get anyone’s attention to review PRs there.

bazel-lib is just a part of what Aspect provides:

Need help? This ruleset has support provided by https://aspect.dev.
See our other Bazel rules: https://github.com/aspect-build

Installation

Installation instructions are included on each release: https://github.com/aspect-build/bazel-lib/releases

Public API

Copying files

copy_directory Copies directories to another package.
copy_file Copies files to another package.
copy_to_bin Copies a source file to output tree at the same workspace-relative path.
copy_to_directory Copies and arranges files and directories into a new directory.
write_source_files Write to one or more files or folders in the source tree. Stamp out tests that ensure the sources exist and are up to date.

Transforming files

jq A toolchain and custom rule for running jq, a tool that is “like sed for json”.
yq A toolchain and custom rule for running yq, a “YAML, JSON and XML processor”.

Manipulating paths

directory_path Provide a label to reference some path within a directory, via DirectoryPathInfo.
output_files Forwards a subset of the files (via the DefaultInfo provider) from a given target's DefaultInfo or OutputGroupInfo.

Writing rules

expand_make_vars Perform make variable and location substitions in strings and templates.
paths Useful path resolution methods.
transitions Transition sources to a provided platform.
utils Various utils for labels and globs.
params_file Generate encoded params file from a list of arguments.
repo_utils Useful methods for repository rule implementations.
run_binary Like skylib's run_binary but adds directory output support.
stamping Support version stamping in custom rules.
base64 Starlark Base64 encoder & decoder.

Generating documentation

docs Rules for generating docs and stamping tests to ensure they are up to date.