Bazel build rules for github repositories.
github_repository
github_repository is a workspace rule that makes it easy to install Github releases into Bazel.
It simplifies running software from Github by using Github releases and Bazel as a way to install and update the packages locally.
Usage
Import github_repostiory to a Bazel workspace
git_repository(
name="rules_github",
url="https://github.com/jerrymarino/rules_github.git",
branch="master"
)
load("@rules_github//:repository.bzl", "github_repository")
Next, setup packages
# Add the binary `rg` from BurntSushi/ripgrep
github_repository(
name = "rg",
owner = "BurntSushi",
repository = "ripgrep",
)
"build" the binary with bazel
bazel build @rg//:rg
After download, the binary is available in bazel-bin/external/rg.
note: it's possible to use bazel run, which has performance overhead compared to running the program directly.
Loading Bazel built Github programs onto the path
After "building" the github_repository's, they are available in the directory, bazel-bin.
# Add `bazel-bin` to the path
export PATH="$PATH:$(find bazel-bin/external -d 1 -type d | tr '\n' ':')"
Caveats
Transitive build dependencies
For many releases, transitive dependencies may be compiled into the release
binary. For building packages from source, Bazel needs transitive dependencies
specified. This topic is nuanced and out of scope of rules_github.
FAQ
Why use rules_github instead of git_repository and git archives?
Git archives are useful for storing source code and are widely used for this purpose on github. In many scenarios, source builds aren't ideal as it adds requirements to the build environment and many take significant time.
Does git_repository work here?
Many applications on www.github.com are distributed in a pre-built binary form - git_repository won't work for this situation. github_repository works because it is integrated into the github API.
When does it update the packages
The Bazel repository_rule documentation contains a detailed explanation of this topic.