npm_import.md

Repository rule to fetch npm packages.

Load this with,

load("@aspect_rules_js//npm:repositories.bzl", "npm_import")

This uses Bazel's downloader to fetch the packages. You can use this to redirect all fetches through a store like Artifactory.

See <https://blog.aspect.build/configuring-bazels-downloader> for more info about how it works and how to configure it.

See npm_translate_lock for the primary user-facing API to fetch npm packages for a given lockfile.

npm_import

npm_import(name, package, version, deps, extra_build_content, transitive_closure, root_package,
           link_workspace, link_packages, lifecycle_hooks, lifecycle_hooks_execution_requirements,
           lifecycle_hooks_env, lifecycle_hooks_use_default_shell_env, integrity, url, commit,
           replace_package, package_visibility, patch_args, patches, custom_postinstall, npm_auth,
           npm_auth_basic, npm_auth_username, npm_auth_password, bins, dev, kwargs)

Import a single npm package into Bazel.

Normally you'd want to use npm_translate_lock to import all your packages at once. It generates npm_import rules. You can create these manually if you want to have exact control.

Bazel will only fetch the given package from an external registry if the package is required for the user-requested targets to be build/tested.

This is a repository rule, which should be called from your WORKSPACE file or some .bzl file loaded from it. For example, with this code in WORKSPACE:

npm_import(
    name = "npm__at_types_node__15.12.2",
    package = "@types/node",
    version = "15.12.2",
    integrity = "sha512-zjQ69G564OCIWIOHSXyQEEDpdpGl+G348RAKY0XXy9Z5kU9Vzv1GMNnkar/ZJ8dzXB3COzD9Mo9NtRZ4xfgUww==",
)

This is similar to Bazel rules in other ecosystems named "_import" like apple_bundle_import, scala_import, java_import, and py_import. go_repository is also a model for this rule.

The name of this repository should contain the version number, so that multiple versions of the same package don't collide. (Note that the npm ecosystem always supports multiple versions of a library depending on where it is required, unlike other languages like Go or Python.)

To consume the downloaded package in rules, it must be "linked" into the link package in the package's BUILD.bazel file:

load("@npm__at_types_node__15.12.2__links//:defs.bzl", npm_link_types_node = "npm_link_imported_package")

npm_link_types_node(name = "node_modules")

This links @types/node into the node_modules of this package with the target name :node_modules/@types/node.

A :node_modules/@types/node/dir filegroup target is also created that provides the the directory artifact of the npm package. This target can be used to create entry points for binary target or to access files within the npm package.

NB: You can choose any target name for the link target but we recommend using the node_modules/@scope/name and node_modules/name convention for readability.

When using npm_translate_lock, you can link all the npm dependencies in the lock file for a package:

load("@npm//:defs.bzl", "npm_link_all_packages")

npm_link_all_packages(name = "node_modules")

This creates :node_modules/name and :node_modules/@scope/name targets for all direct npm dependencies in the package. It also creates :node_modules/name/dir and :node_modules/@scope/name/dir filegroup targets that provide the the directory artifacts of their npm packages. These target can be used to create entry points for binary target or to access files within the npm package.

If you have a mix of npm_link_all_packages and npm_link_imported_package functions to call you can pass the npm_link_imported_package link functions to the imported_links attribute of npm_link_all_packages to link them all in one call. For example,

load("@npm//:defs.bzl", "npm_link_all_packages")
load("@npm__at_types_node__15.12.2__links//:defs.bzl", npm_link_types_node = "npm_link_imported_package")

npm_link_all_packages(
    name = "node_modules",
    imported_links = [
        npm_link_types_node,
    ]
)

This has the added benefit of adding the imported_links to the convienence :node_modules target which includes all direct dependencies in that package.

NB: You can pass an name to npm_link_all_packages and this will change the targets generated to "{name}/@scope/name" and "{name}/name". We recommend using "node_modules" as the convention for readability.

To change the proxy URL we use to fetch, configure the Bazel downloader:

1. Make a file containing a rewrite rule like

   rewrite (registry.npmjs.org)/(.*) artifactory.build.internal.net/artifactory/$1/$2

2. To understand the rewrites, see UrlRewriterConfig in Bazel sources.

3. Point bazel to the config with a line in .bazelrc like common --experimental_downloader_config=.bazel_downloader_config

Read more about the downloader config: https://blog.aspect.build/configuring-bazels-downloader

PARAMETERS

Name	Description	Default Value
name	Name for this repository rule	none
package	Name of the npm package, such as acorn or @types/node	none
version	Version of the npm package, such as 8.4.0	none
deps	A dict other npm packages this one depends on where the key is the package name and value is the version	{}
extra_build_content	Additional content to append on the generated BUILD file at the root of the created repository, either as a string or a list of lines similar to https://github.com/bazelbuild/bazel-skylib/blob/main/docs/write_file_doc.md.	""
transitive_closure	A dict all npm packages this one depends on directly or transitively where the key is the package name and value is a list of version(s) depended on in the closure.	{}
root_package	The root package where the node_modules package store is linked to. Typically this is the package that the pnpm-lock.yaml file is located when using npm_translate_lock.	""
link_workspace	The workspace name where links will be created for this package. This is typically set in rule sets and libraries that are to be consumed as external repositories so links are created in the external repository and not the user workspace. Can be left unspecified if the link workspace is the user workspace.	""
link_packages	Dict of paths where links may be created at for this package to a list of link aliases to link as in each package. If aliases are an empty list this indicates to link as the package name. Defaults to {} which indicates that links may be created in any package as specified by the direct attribute of the generated npm_link_package.	{}
lifecycle_hooks	List of lifecycle hook package.json scripts to run for this package if they exist.	[]
lifecycle_hooks_execution_requirements	Execution requirements when running the lifecycle hooks. For example: lifecycle_hooks_execution_requirements: ["no-sandbox', "requires-network"] This defaults to ["no-sandbox"] to limit the overhead of sandbox creation and copying the output TreeArtifact out of the sandbox.	["no-sandbox"]
lifecycle_hooks_env	Environment variables set for the lifecycle hooks action for this npm package if there is one. Environment variables are defined by providing an array of "key=value" entries. For example: lifecycle_hooks_env: ["PREBULT_BINARY=https://downloadurl"],	[]
lifecycle_hooks_use_default_shell_env	If True, the use_default_shell_env attribute of lifecycle hook actions is set to True. See use_default_shell_env Note: --incompatible_merge_fixed_and_default_shell_env is often required and not enabled by default in Bazel < 7.0.0. This defaults to False reduce the negative effects of use_default_shell_env. Requires bazel-lib >= 2.4.2.	False
integrity	Expected checksum of the file downloaded, in Subresource Integrity format. This must match the checksum of the file downloaded. This is the same as appears in the pnpm-lock.yaml, yarn.lock or package-lock.json file. It is a security risk to omit the checksum as remote files can change. At best omitting this field will make your build non-hermetic. It is optional to make development easier but should be set before shipping.	""
url	Optional url for this package. If unset, a default npm registry url is generated from the package name and version. May start with git+ssh:// or git+https:// to indicate a git repository. For example, git+ssh://git@github.com/org/repo.git If url is configured as a git repository, the commit attribute must be set to the desired commit.	""
commit	Specific commit to be checked out if url is a git repository.	""
replace_package	Use the specified npm_package target when linking instead of the fetched sources for this npm package. The injected npm_package target may optionally contribute transitive npm package dependencies on top of the transitive dependencies specified in the pnpm lock file for the same package, however, these transitive dependencies must not collide with pnpm lock specified transitive dependencies. Any patches specified for this package will be not applied to the injected npm_package target. They will be applied, however, to the fetches sources so they can still be useful for patching the fetched package.json file, which is used to determine the generated bin entries for the package. NB: lifecycle hooks and custom_postinstall scripts, if implicitly or explicitly enabled, will be run on the injected npm_package. These may be disabled explicitly using the lifecycle_hooks attribute.	None
package_visibility	Visibility of generated node_module link targets.	["//visibility:public"]
patch_args	Arguments to pass to the patch tool. -p1 will usually be needed for patches generated by git.	["-p0"]
patches	Patch files to apply onto the downloaded npm package.	[]
custom_postinstall	Custom string postinstall script to run on the installed npm package. Runs after any existing lifecycle hooks if any are enabled.	""
npm_auth	Auth token to authenticate with npm. When using Bearer authentication.	""
npm_auth_basic	Auth token to authenticate with npm. When using Basic authentication. This is typically the base64 encoded string "username:password".	""
npm_auth_username	Auth username to authenticate with npm. When using Basic authentication.	""
npm_auth_password	Auth password to authenticate with npm. When using Basic authentication.	""
bins	Dictionary of node_modules/.bin binary files to create mapped to their node entry points. This is typically derived from the "bin" attribute in the package.json file of the npm package being linked. For example: bins = { "foo": "./foo.js", "bar": "./bar.js", } In the future, this field may be automatically populated by npm_translate_lock from information in the pnpm lock file. That feature is currently blocked on pnpm/pnpm#5131.	{}
dev	Whether this npm package is a dev dependency	False
kwargs	Internal use only	none