One advantage of open-source software is that you can make your own changes that suit your needs.
@rules_nodejs module can simply be fetched from sources in place of the published distribution.
For example, in place of
http_archive( name = "rules_nodejs", sha256 = "...", urls = ["https://github.com/bazelbuild/rules_nodejs/releases/download/5.0.0/rules_nodejs-core-5.0.0.tar.gz"], )
you can just use a commit from your fork:
http_archive( name = "rules_nodejs", sha256 = "...", strip_prefix = "rules_nodejs-abcd123", url = "https://github.com/my-org/rules_nodejs/archive/abcd123.tar.gz", )
@build_bazel_rules_nodejs module distributed on GitHub releases is harder to work with.
It has different content from the sources in this repo.
This is true for packages published to
@bazel/ on npm as well.
These packages have only runtime bazel dependencies, but the sources depend on development dependencies. For example, the
@bazel_skylib library is a development-time transitive dependency, while an npm package would have that dependency statically linked in.
If you have a small change, it's easiest to just patch the distributed artifacts rather than build from source. However if you're doing active development in rules_nodejs or have a policy of not depending on release artifacts, it's possible to depend directly on sources. This is not yet documented; file an issue on our repo if you think you need this.
Patching the npm packages
The pattern we use most commonly is to use patch-package. To store your local changes to the npm packages follow the steps:
npm i -D patch-package
- Edit the target package in your
npx patch-package <npm package>. This will store the patch in the
patches/directory in the root of the workspace
"postinstall": "patch-package"to the
package.jsonin your repo to apply the patches when building dependencies (aka at
Patching the build_bazel_rules_nodejs release
build_bazel_rules_nodejs has a distribution format which is a tgz published to GitHub, and this can make it tricky to make casual changes without forking the project and building your own release artifacts.
Bazel has a handy patching mechanism that lets you easily apply a local patch to the release artifact for built-in rules: the
patches attribute to
First, make your changes in a clone of the rules_nodejs repo. Export a patch file simply using
git diff > my.patch
Then copy the patch file somewhere in your repo and point to it from your
http_archive( name = "build_bazel_rules_nodejs", patch_args = ["-p1"], patches = ["//path/to/my.patch"], sha256 = "6d4edbf28ff6720aedf5f97f9b9a7679401bf7fca9d14a0fff80f644a99992b4", urls = ["https://github.com/bazelbuild/rules_nodejs/releases/download/0.32.2/rules_nodejs-0.32.2.tar.gz"], )