title: Built-ins layout: default stylesheet: docs

Built-in rules

These rules are available without any npm installation, via the WORKSPACE install of the build_bazel_rules_nodejs workspace. This is necessary to bootstrap Bazel to run the package manager to download other rules from NPM.

node_repositories

To be run in user's WORKSPACE to install rules_nodejs dependencies.

This rule sets up node, npm, and yarn.

The versions of these tools can be specified in one of three ways:

  • Simplest Usage: Specify no explicit versions. This will download and use the latest NodeJS & Yarn that were available when the version of rules_nodejs you‘re using was released. Note that you can skip calling node_repositories in your WORKSPACE file - if you later try to yarn_install or npm_install, we’ll automatically select this simple usage for you.
  • Forced version(s): You can select the version of NodeJS and/or Yarn to download & use by specifying it when you call node_repositories, using a value that matches a known version (see the default values)
  • Using a custom version: You can pass in a custom list of NodeJS and/or Yarn repositories and URLs for node_resositories to use.
  • Using a local version: To avoid downloads, you can check in vendored copies of NodeJS and/or Yarn and set vendored_node and or vendored_yarn to point to those before calling node_repositories. You can also point to a location where node is installed on your computer, but we don't recommend this because it leads to version skew between you, your coworkers, and your Continuous Integration environment. It also ties your build to a single platform, preventing you from cross-compiling into a Linux docker image on Mac for example.

See the the repositories documentation for how to use the resulting repositories.

Creating dependency installation scripts for manually-managed dependencies

You can optionally pass a package_json array to node_repositories. This lets you use Bazel‘s version of yarn or npm, yet always run the package manager yourself. This is an advanced scenario you can use in place of the npm_install or yarn_install rules, but we don’t recommend it, and might remove it in the future.

Example:

load("@build_bazel_rules_nodejs//:index.bzl", "node_repositories")
node_repositories(package_json = ["//:package.json", "//subpkg:package.json"])

Running bazel run @nodejs//:yarn_node_repositories in this repo would create /node_modules and /subpkg/node_modules.

Note that the dependency installation scripts will run in each subpackage indicated by the package_json attribute.

Usage

node_repositories(name, node_repositories, node_urls, node_version, package_json, preserve_symlinks, vendored_node, vendored_yarn, yarn_repositories, yarn_urls, yarn_version)

name

(name, mandatory): A unique name for this repository.

node_repositories

(Dictionary: String -> List of strings): Custom list of node repositories to use

A dictionary mapping NodeJS versions to sets of hosts and their corresponding (filename, strip_prefix, sha256) tuples. You should list a node binary for every platform users have, likely Mac, Windows, and Linux.

For example,

node_repositories(
    node_repositories = {
        "10.10.0-darwin_amd64": ("node-v10.10.0-darwin-x64.tar.gz", "node-v10.10.0-darwin-x64", "00b7a8426e076e9bf9d12ba2d571312e833fe962c70afafd10ad3682fdeeaa5e"),
        "10.10.0-linux_amd64": ("node-v10.10.0-linux-x64.tar.xz", "node-v10.10.0-linux-x64", "686d2c7b7698097e67bcd68edc3d6b5d28d81f62436c7cf9e7779d134ec262a9"),
        "10.10.0-windows_amd64": ("node-v10.10.0-win-x64.zip", "node-v10.10.0-win-x64", "70c46e6451798be9d052b700ce5dadccb75cf917f6bf0d6ed54344c856830cfb"),
    },
)

Defaults to {"8.9.1-darwin_amd64": ("node-v8.9.1-darwin-x64.tar.gz", "node-v8.9.1-darwin-x64", "05c992a6621d28d564b92bf3051a5dc0adf83839237c0d4653a8cdb8a1c73b94"), "8.9.1-linux_amd64": ("node-v8.9.1-linux-x64.tar.xz", "node-v8.9.1-linux-x64", "8be82805f7c1ab3e64d4569fb9a90ded2de78dd27cadbb91bad1bf975dae1e2d"), "8.9.1-windows_amd64": ("node-v8.9.1-win-x64.zip", "node-v8.9.1-win-x64", "db89c6e041da359561fbe7da075bb4f9881a0f7d3e98c203e83732cfb283fa4a"), "8.11.1-darwin_amd64": ("node-v8.11.1-darwin-x64.tar.gz", "node-v8.11.1-darwin-x64", "5c7b05899ff56910a2b8180f139d48612f349ac2c5d20f08dbbeffbed9e3a089"), "8.11.1-linux_amd64": ("node-v8.11.1-linux-x64.tar.xz", "node-v8.11.1-linux-x64", "6617e245fa0f7fbe0e373e71d543fea878315324ab31dc64b4eba10e42d04c11"), "8.11.1-windows_amd64": ("node-v8.11.1-win-x64.zip", "node-v8.11.1-win-x64", "7d49b59c2b5d73a14c138e8a215d558a64a5241cd5035d9824f608e7bba097b1"), "8.12.0-darwin_amd64": ("node-v8.12.0-darwin-x64.tar.gz", "node-v8.12.0-darwin-x64", "ca131b84dfcf2b6f653a6521d31f7a108ad7d83f4d7e781945b2eca8172064aa"), "8.12.0-linux_amd64": ("node-v8.12.0-linux-x64.tar.xz", "node-v8.12.0-linux-x64", "29a20479cd1e3a03396a4e74a1784ccdd1cf2f96928b56f6ffa4c8dae40c88f2"), "8.12.0-windows_amd64": ("node-v8.12.0-win-x64.zip", "node-v8.12.0-win-x64", "9b22c9b23148b61ea0052826b3ac0255b8a3a542c125272b8f014f15bf11b091"), "9.11.1-darwin_amd64": ("node-v9.11.1-darwin-x64.tar.gz", "node-v9.11.1-darwin-x64", "7b1fb394aa41a62b477e36df16644bd383cc9084808511f6cd318b835a06aac6"), "9.11.1-linux_amd64": ("node-v9.11.1-linux-x64.tar.xz", "node-v9.11.1-linux-x64", "4d27a95d5c2f1c8ef99118794c9c4903e63963418d3e16ca7576760cff39879b"), "9.11.1-windows_amd64": ("node-v9.11.1-win-x64.zip", "node-v9.11.1-win-x64", "0a3566d57ccb7fed95d18fc6c3bc1552a1b1e4753f9bc6c5d45e04f325e1ee53"), "10.3.0-darwin_amd64": ("node-v10.3.0-darwin-x64.tar.gz", "node-v10.3.0-darwin-x64", "0bb5b7e3fe8cccda2abda958d1eb0408f1518a8b0cb58b75ade5d507cd5d6053"), "10.3.0-linux_amd64": ("node-v10.3.0-linux-x64.tar.xz", "node-v10.3.0-linux-x64", "eb3c3e2585494699716ad3197c8eedf4003d3f110829b30c5a0dc34414c47423"), "10.3.0-windows_amd64": ("node-v10.3.0-win-x64.zip", "node-v10.3.0-win-x64", "65d586afb087406a2800d8e51f664c88b26d510f077b85a3b177a1bb79f73677"), "10.9.0-darwin_amd64": ("node-v10.9.0-darwin-x64.tar.gz", "node-v10.9.0-darwin-x64", "3c4fe75dacfcc495a432a7ba2dec9045cff359af2a5d7d0429c84a424ef686fc"), "10.9.0-linux_amd64": ("node-v10.9.0-linux-x64.tar.xz", "node-v10.9.0-linux-x64", "c5acb8b7055ee0b6ac653dc4e458c5db45348cecc564b388f4ed1def84a329ff"), "10.9.0-windows_amd64": ("node-v10.9.0-win-x64.zip", "node-v10.9.0-win-x64", "6a75cdbb69d62ed242d6cbf0238a470bcbf628567ee339d4d098a5efcda2401e"), "10.10.0-darwin_amd64": ("node-v10.10.0-darwin-x64.tar.gz", "node-v10.10.0-darwin-x64", "00b7a8426e076e9bf9d12ba2d571312e833fe962c70afafd10ad3682fdeeaa5e"), "10.10.0-linux_amd64": ("node-v10.10.0-linux-x64.tar.xz", "node-v10.10.0-linux-x64", "686d2c7b7698097e67bcd68edc3d6b5d28d81f62436c7cf9e7779d134ec262a9"), "10.10.0-windows_amd64": ("node-v10.10.0-win-x64.zip", "node-v10.10.0-win-x64", "70c46e6451798be9d052b700ce5dadccb75cf917f6bf0d6ed54344c856830cfb"), "10.13.0-darwin_amd64": ("node-v10.13.0-darwin-x64.tar.gz", "node-v10.13.0-darwin-x64", "815a5d18516934a3963ace9f0574f7d41f0c0ce9186a19be3d89e039e57598c5"), "10.13.0-linux_amd64": ("node-v10.13.0-linux-x64.tar.xz", "node-v10.13.0-linux-x64", "0dc6dba645550b66f8f00541a428c29da7c3cde32fb7eda2eb626a9db3bbf08d"), "10.13.0-windows_amd64": ("node-v10.13.0-win-x64.zip", "node-v10.13.0-win-x64", "eb09c9e9677f1919ec1ca78623c09b2a718ec5388b72b7662d5c41e5f628a52c"), "10.16.0-darwin_amd64": ("node-v10.16.0-darwin-x64.tar.gz", "node-v10.16.0-darwin-x64", "6c009df1b724026d84ae9a838c5b382662e30f6c5563a0995532f2bece39fa9c"), "10.16.0-linux_amd64": ("node-v10.16.0-linux-x64.tar.xz", "node-v10.16.0-linux-x64", "1827f5b99084740234de0c506f4dd2202a696ed60f76059696747c34339b9d48"), "10.16.0-windows_amd64": ("node-v10.16.0-win-x64.zip", "node-v10.16.0-win-x64", "aa22cb357f0fb54ccbc06b19b60e37eefea5d7dd9940912675d3ed988bf9a059"), "12.13.0-darwin_amd64": ("node-v12.13.0-darwin-x64.tar.gz", "node-v12.13.0-darwin-x64", "49a7374670a111b033ce16611b20fd1aafd3296bbc662b184fe8fb26a29c22cc"), "12.13.0-linux_amd64": ("node-v12.13.0-linux-x64.tar.xz", "node-v12.13.0-linux-x64", "7a57ef2cb3036d7eacd50ae7ba07245a28336a93652641c065f747adb2a356d9"), "12.13.0-windows_amd64": ("node-v12.13.0-win-x64.zip", "node-v12.13.0-win-x64", "6f920cebeecb4957b4ef0def6d9b04c49d4582864f8d1a207ce8d0665865781a")}

node_urls

(List of strings): custom list of URLs to use to download NodeJS

Each entry is a template for downloading a node distribution.

The {version} parameter is substituted with the node_version attribute, and {filename} with the matching entry from the node_repositories attribute.

For example, given

node_repositories(
    node_version = "10.10.0",
    node_repositories = {"10.10.0-darwin_amd64": ("node-v10.10.0-darwin-x64.tar.gz", "node-v10.10.0-darwin-x64", "00b7a8426e076e9bf9d12ba2d571312e833fe962c70afafd10ad3682fdeeaa5e")},
    node_urls = ["https://mycorpproxy/mirror/node/v{version}/{filename}"],
)

A Mac client will try to download node from https://mycorpproxy/mirror/node/v10.10.0/node-v10.10.0-darwin-x64.tar.gz and expect that file to have sha256sum 00b7a8426e076e9bf9d12ba2d571312e833fe962c70afafd10ad3682fdeeaa5e

Defaults to ["https://mirror.bazel.build/nodejs.org/dist/v{version}/{filename}", "https://nodejs.org/dist/v{version}/{filename}"]

node_version

(String): the specific version of NodeJS to install or, if vendored_node is specified, the vendored version of node

Defaults to "12.13.0"

package_json

(labels): (ADVANCED, not recommended) a list of labels, which indicate the package.json files that will be installed when you manually run the package manager, e.g. with bazel run @nodejs//:yarn_node_repositories or bazel run @nodejs//:npm_node_repositories install. If you use bazel-managed dependencies, you should omit this attribute.

Defaults to []

preserve_symlinks

(Boolean): Turn on --node_options=--preserve-symlinks for nodejs_binary and nodejs_test rules.

When this option is turned on, node will preserve the symlinked path for resolves instead of the default behavior of resolving to the real path. This means that all required files must be in be included in your runfiles as it prevents the default behavior of potentially resolving outside of the runfiles. For example, all required files need to be included in your node_modules filegroup. This option is desirable as it gives a stronger guarantee of hermeticity which is required for remote execution.

Defaults to True

vendored_node

(label): the local path to a pre-installed NodeJS runtime.

If set then also set node_version to the version that of node that is vendored. Bazel will automatically turn on features such as --preserve-symlinks-main if they are supported by the node version being used.

Defaults to None

vendored_yarn

(label): the local path to a pre-installed yarn tool

Defaults to None

yarn_repositories

(Dictionary: String -> List of strings): Custom list of yarn repositories to use.

Dictionary mapping Yarn versions to their corresponding (filename, strip_prefix, sha256) tuples.

For example,

node_repositories(
    yarn_repositories = {
        "1.12.1": ("yarn-v1.12.1.tar.gz", "yarn-v1.12.1", "09bea8f4ec41e9079fa03093d3b2db7ac5c5331852236d63815f8df42b3ba88d"),
    },
)

Defaults to {"1.3.2": ("yarn-v1.3.2.tar.gz", "yarn-v1.3.2", "6cfe82e530ef0837212f13e45c1565ba53f5199eec2527b85ecbcd88bf26821d"), "1.5.1": ("yarn-v1.5.1.tar.gz", "yarn-v1.5.1", "cd31657232cf48d57fdbff55f38bfa058d2fb4950450bd34af72dac796af4de1"), "1.6.0": ("yarn-v1.6.0.tar.gz", "yarn-v1.6.0", "a57b2fdb2bfeeb083d45a883bc29af94d5e83a21c25f3fc001c295938e988509"), "1.9.2": ("yarn-v1.9.2.tar.gz", "yarn-v1.9.2", "3ad69cc7f68159a562c676e21998eb21b44138cae7e8fe0749a7d620cf940204"), "1.9.4": ("yarn-v1.9.4.tar.gz", "yarn-v1.9.4", "7667eb715077b4bad8e2a832e7084e0e6f1ba54d7280dc573c8f7031a7fb093e"), "1.12.1": ("yarn-v1.12.1.tar.gz", "yarn-v1.12.1", "09bea8f4ec41e9079fa03093d3b2db7ac5c5331852236d63815f8df42b3ba88d"), "1.12.3": ("yarn-v1.12.3.tar.gz", "yarn-v1.12.3", "02cd4b589ec22c4bdbd2bc5ebbfd99c5e99b07242ad68a539cb37896b93a24f2"), "1.13.0": ("yarn-v1.13.0.tar.gz", "yarn-v1.13.0", "125d40ebf621ebb08e3f66a618bd2cc5cd77fa317a312900a1ab4360ed38bf14"), "1.19.1": ("yarn-v1.19.1.tar.gz", "yarn-v1.19.1", "34293da6266f2aae9690d59c2d764056053ff7eebc56b80b8df05010c3da9343"), "1.22.4": ("yarn-v1.22.4.tar.gz", "yarn-v1.22.4", "bc5316aa110b2f564a71a3d6e235be55b98714660870c5b6b2d2d3f12587fb58")}

yarn_urls

(List of strings): custom list of URLs to use to download Yarn

Each entry is a template, similar to the node_urls attribute, using yarn_version and yarn_repositories in the substitutions.

For example,

node_repositories(
    yarn_repositories = {
        "1.12.1": ("yarn-v1.12.1.tar.gz", "yarn-v1.12.1", "09bea8f4ec41e9079fa03093d3b2db7ac5c5331852236d63815f8df42b3ba88d"),
    },
    yarn_version = "1.12.1",
    yarn_urls = [
        "https://github.com/yarnpkg/yarn/releases/download/v{version}/{filename}",
    ],
)

Will download yarn from https://github.com/yarnpkg/yarn/releases/download/v1.2.1/yarn-v1.12.1.tar.gzand expect the file to have sha256sum09bea8f4ec41e9079fa03093d3b2db7ac5c5331852236d63815f8df42b3ba88d`.

Defaults to ["https://mirror.bazel.build/github.com/yarnpkg/yarn/releases/download/v{version}/{filename}", "https://github.com/yarnpkg/yarn/releases/download/v{version}/{filename}"]

yarn_version

(String): the specific version of Yarn to install

Defaults to "1.19.1"

nodejs_binary

Runs some JavaScript code in NodeJS.

Usage

nodejs_binary(name, configuration_env_vars, data, default_env_vars, entry_point, install_source_map_support, node_modules, templated_args)

name

(name, mandatory): A unique name for this target.

configuration_env_vars

(List of strings): Pass these configuration environment variables to the resulting binary. Chooses a subset of the configuration environment variables (taken from ctx.var), which also includes anything specified via the --define flag. Note, this can lead to different outputs produced by this rule.

Defaults to []

data

(labels): Runtime dependencies which may be loaded during execution.

Defaults to []

default_env_vars

(List of strings): Default environment variables that are added to configuration_env_vars.

This is separate from the default of configuration_env_vars so that a user can set configuration_env_vars without losing the defaults that should be set in most cases.

The set of default environment variables is:

  • VERBOSE_LOGS: use by some rules & tools to turn on debug output in their logs
  • NODE_DEBUG: used by node.js itself to print more logs
  • RUNFILES_LIB_DEBUG: print diagnostic message from Bazel runfiles.bash helper

Defaults to ["VERBOSE_LOGS", "NODE_DEBUG", "RUNFILES_LIB_DEBUG"]

entry_point

(label, mandatory): The script which should be executed first, usually containing a main function.

If the entry JavaScript file belongs to the same package (as the BUILD file), you can simply reference it by its relative name to the package directory:

nodejs_binary(
    name = "my_binary",
    ...
    entry_point = ":file.js",
)

You can specify the entry point as a typescript file so long as you also include the ts_library target in data:

ts_library(
    name = "main",
    srcs = ["main.ts"],
)

nodejs_binary(
    name = "bin",
    data = [":main"]
    entry_point = ":main.ts",
)

The rule will use the corresponding .js output of the ts_library rule as the entry point.

If the entry point target is a rule, it should produce a single JavaScript entry file that will be passed to the nodejs_binary rule. For example:

filegroup(
    name = "entry_file",
    srcs = ["main.js"],
)

nodejs_binary(
    name = "my_binary",
    entry_point = ":entry_file",
)

The entry_point can also be a label in another workspace:

nodejs_binary(
    name = "history-server",
    entry_point = "@npm//:node_modules/history-server/modules/cli.js",
    data = ["@npm//history-server"],
)

install_source_map_support

(Boolean): Install the source-map-support package. Enable this to get stack traces that point to original sources, e.g. if the program was written in TypeScript.

Defaults to True

node_modules

(label): The npm packages which should be available to require() during execution.

This attribute is DEPRECATED. As of version 0.13.0 the recommended approach to npm dependencies is to use fine grained npm dependencies which are setup with the yarn_install or npm_install rules. For example, in targets that used a //:node_modules filegroup,

nodejs_binary(
    name = "my_binary",
    ...
    node_modules = "//:node_modules",
)

which specifies all files within the //:node_modules filegroup to be inputs to the my_binary. Using fine grained npm dependencies, my_binary is defined with only the npm dependencies that are needed:

nodejs_binary(
    name = "my_binary",
    ...
    data = [
        "@npm//foo",
        "@npm//bar",
        ...
    ],
)

In this case, only the foo and bar npm packages and their transitive deps are includes as inputs to the my_binary target which reduces the time required to setup the runfiles for this target (see https://github.com/bazelbuild/bazel/issues/5153).

The @npm external repository and the fine grained npm package targets are setup using the yarn_install or npm_install rule in your WORKSPACE file:

yarn_install( name = “npm”, package_json = “//:package.json”, yarn_lock = “//:yarn.lock”, )

For other rules such as jasmine_node_test, fine grained npm dependencies are specified in the deps attribute:

jasmine_node_test(
    name = "my_test",
    ...
    deps = [
        "@npm//jasmine",
        "@npm//foo",
        "@npm//bar",
        ...
    ],
)

Defaults to //:node_modules_none

templated_args

(List of strings): Arguments which are passed to every execution of the program. To pass a node startup option, prepend it with --node_options=, e.g. --node_options=--preserve-symlinks.

Subject to ‘Make variable’ substitution. See https://docs.bazel.build/versions/master/be/make-variables.html.

  1. Subject to predefined source/output path variables substitutions.

The predefined variables execpath, execpaths, rootpath, rootpaths, location, and locations take label parameters (e.g. $(execpath //foo:bar)) and substitute the file paths denoted by that label.

See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_label_variables for more info.

NB: This $(location) substition returns the manifest file path which differs from the *_binary & *_test args and genrule bazel substitions. This will be fixed in a future major release. See docs string of expand_location_into_runfiles macro in internal/common/expand_into_runfiles.bzl for more info.

The recommended approach is to now use $(rootpath) where you previously used $(location).

To get from a $(rootpath) to the absolute path that $$(rlocation $(location)) returned you can either use $$(rlocation $(rootpath)) if you are in the templated_args of a nodejs_binary or nodejs_test:

BUILD.bazel:

nodejs_test(
    name = "my_test",
    data = [":bootstrap.js"],
    templated_args = ["--node_options=--require=$$(rlocation $(rootpath :bootstrap.js))"],
)

or if you're in the context of a .js script you can pass the $(rootpath) as an argument to the script and use the javascript runfiles helper to resolve to the absolute path:

BUILD.bazel:

nodejs_test(
    name = "my_test",
    data = [":some_file"],
    entry_point = ":my_test.js",
    templated_args = ["$(rootpath :some_file)"],
)

my_test.js

const runfiles = require(process.env['BAZEL_NODE_RUNFILES_HELPER']);
const args = process.argv.slice(2);
const some_file = runfiles.resolveWorkspaceRelative(args[0]);

NB: Bazel will error if it sees the single dollar sign $(rlocation path) in templated_args as it will try to expand $(rlocation) since we now expand predefined & custom “make” variables such as $(COMPILATION_MODE), $(BINDIR) & $(TARGET_CPU) using ctx.expand_make_variables. See https://docs.bazel.build/versions/master/be/make-variables.html.

To prevent expansion of $(rlocation) write it as $$(rlocation). Bazel understands $$ to be the string literal $ and the expansion results in $(rlocation) being passed as an arg instead of being expanded. $(rlocation) is then evaluated by the bash node launcher script and it calls the rlocation function in the runfiles.bash helper. For example, the templated arg $$(rlocation $(rootpath //:some_file)) is expanded by Bazel to $(rlocation ./some_file) which is then converted in bash to the absolute path of //:some_file in runfiles by the runfiles.bash helper before being passed as an argument to the program.

NB: nodejs_binary and nodejs_test will preserve the legacy behavior of $(rlocation) so users don't need to update to $$(rlocation). This may be changed in the future.

  1. Subject to predefined variables & custom variable substitutions.

Predefined “Make” variables such as $(COMPILATION_MODE) and $(TARGET_CPU) are expanded. See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_variables.

Custom variables are also expanded including variables set through the Bazel CLI with --define=SOME_VAR=SOME_VALUE. See https://docs.bazel.build/versions/master/be/make-variables.html#custom_variables.

Predefined genrule variables are not supported in this context.

Defaults to []

nodejs_test

Identical to nodejs_binary, except this can be used with bazel test as well. When the binary returns zero exit code, the test passes; otherwise it fails.

nodejs_test is a convenient way to write a novel kind of test based on running your own test runner. For example, the ts-api-guardian library has a way to assert the public API of a TypeScript program, and uses nodejs_test here: https://github.com/angular/angular/blob/master/tools/ts-api-guardian/index.bzl

If you just want to run a standard test using a test runner like Karma or Jasmine, use the specific rules for those test runners, e.g. jasmine_node_test.

To debug a Node.js test, we recommend saving a group of flags together in a “config”. Put this in your tools/bazel.rc so it's shared with your team:

# Enable debugging tests with --config=debug
test:debug --test_arg=--node_options=--inspect-brk --test_output=streamed --test_strategy=exclusive --test_timeout=9999 --nocache_test_results

Now you can add --config=debug to any bazel test command line. The runtime will pause before executing the program, allowing you to connect a remote debugger.

Usage

nodejs_test(name, configuration_env_vars, data, default_env_vars, entry_point, expected_exit_code, install_source_map_support, node_modules, templated_args)

name

(name, mandatory): A unique name for this target.

configuration_env_vars

(List of strings): Pass these configuration environment variables to the resulting binary. Chooses a subset of the configuration environment variables (taken from ctx.var), which also includes anything specified via the --define flag. Note, this can lead to different outputs produced by this rule.

Defaults to []

data

(labels): Runtime dependencies which may be loaded during execution.

Defaults to []

default_env_vars

(List of strings): Default environment variables that are added to configuration_env_vars.

This is separate from the default of configuration_env_vars so that a user can set configuration_env_vars without losing the defaults that should be set in most cases.

The set of default environment variables is:

  • VERBOSE_LOGS: use by some rules & tools to turn on debug output in their logs
  • NODE_DEBUG: used by node.js itself to print more logs
  • RUNFILES_LIB_DEBUG: print diagnostic message from Bazel runfiles.bash helper

Defaults to ["VERBOSE_LOGS", "NODE_DEBUG", "RUNFILES_LIB_DEBUG"]

entry_point

(label, mandatory): The script which should be executed first, usually containing a main function.

If the entry JavaScript file belongs to the same package (as the BUILD file), you can simply reference it by its relative name to the package directory:

nodejs_binary(
    name = "my_binary",
    ...
    entry_point = ":file.js",
)

You can specify the entry point as a typescript file so long as you also include the ts_library target in data:

ts_library(
    name = "main",
    srcs = ["main.ts"],
)

nodejs_binary(
    name = "bin",
    data = [":main"]
    entry_point = ":main.ts",
)

The rule will use the corresponding .js output of the ts_library rule as the entry point.

If the entry point target is a rule, it should produce a single JavaScript entry file that will be passed to the nodejs_binary rule. For example:

filegroup(
    name = "entry_file",
    srcs = ["main.js"],
)

nodejs_binary(
    name = "my_binary",
    entry_point = ":entry_file",
)

The entry_point can also be a label in another workspace:

nodejs_binary(
    name = "history-server",
    entry_point = "@npm//:node_modules/history-server/modules/cli.js",
    data = ["@npm//history-server"],
)

expected_exit_code

(Integer): The expected exit code for the test. Defaults to 0.

Defaults to 0

install_source_map_support

(Boolean): Install the source-map-support package. Enable this to get stack traces that point to original sources, e.g. if the program was written in TypeScript.

Defaults to True

node_modules

(label): The npm packages which should be available to require() during execution.

This attribute is DEPRECATED. As of version 0.13.0 the recommended approach to npm dependencies is to use fine grained npm dependencies which are setup with the yarn_install or npm_install rules. For example, in targets that used a //:node_modules filegroup,

nodejs_binary(
    name = "my_binary",
    ...
    node_modules = "//:node_modules",
)

which specifies all files within the //:node_modules filegroup to be inputs to the my_binary. Using fine grained npm dependencies, my_binary is defined with only the npm dependencies that are needed:

nodejs_binary(
    name = "my_binary",
    ...
    data = [
        "@npm//foo",
        "@npm//bar",
        ...
    ],
)

In this case, only the foo and bar npm packages and their transitive deps are includes as inputs to the my_binary target which reduces the time required to setup the runfiles for this target (see https://github.com/bazelbuild/bazel/issues/5153).

The @npm external repository and the fine grained npm package targets are setup using the yarn_install or npm_install rule in your WORKSPACE file:

yarn_install( name = “npm”, package_json = “//:package.json”, yarn_lock = “//:yarn.lock”, )

For other rules such as jasmine_node_test, fine grained npm dependencies are specified in the deps attribute:

jasmine_node_test(
    name = "my_test",
    ...
    deps = [
        "@npm//jasmine",
        "@npm//foo",
        "@npm//bar",
        ...
    ],
)

Defaults to //:node_modules_none

templated_args

(List of strings): Arguments which are passed to every execution of the program. To pass a node startup option, prepend it with --node_options=, e.g. --node_options=--preserve-symlinks.

Subject to ‘Make variable’ substitution. See https://docs.bazel.build/versions/master/be/make-variables.html.

  1. Subject to predefined source/output path variables substitutions.

The predefined variables execpath, execpaths, rootpath, rootpaths, location, and locations take label parameters (e.g. $(execpath //foo:bar)) and substitute the file paths denoted by that label.

See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_label_variables for more info.

NB: This $(location) substition returns the manifest file path which differs from the *_binary & *_test args and genrule bazel substitions. This will be fixed in a future major release. See docs string of expand_location_into_runfiles macro in internal/common/expand_into_runfiles.bzl for more info.

The recommended approach is to now use $(rootpath) where you previously used $(location).

To get from a $(rootpath) to the absolute path that $$(rlocation $(location)) returned you can either use $$(rlocation $(rootpath)) if you are in the templated_args of a nodejs_binary or nodejs_test:

BUILD.bazel:

nodejs_test(
    name = "my_test",
    data = [":bootstrap.js"],
    templated_args = ["--node_options=--require=$$(rlocation $(rootpath :bootstrap.js))"],
)

or if you're in the context of a .js script you can pass the $(rootpath) as an argument to the script and use the javascript runfiles helper to resolve to the absolute path:

BUILD.bazel:

nodejs_test(
    name = "my_test",
    data = [":some_file"],
    entry_point = ":my_test.js",
    templated_args = ["$(rootpath :some_file)"],
)

my_test.js

const runfiles = require(process.env['BAZEL_NODE_RUNFILES_HELPER']);
const args = process.argv.slice(2);
const some_file = runfiles.resolveWorkspaceRelative(args[0]);

NB: Bazel will error if it sees the single dollar sign $(rlocation path) in templated_args as it will try to expand $(rlocation) since we now expand predefined & custom “make” variables such as $(COMPILATION_MODE), $(BINDIR) & $(TARGET_CPU) using ctx.expand_make_variables. See https://docs.bazel.build/versions/master/be/make-variables.html.

To prevent expansion of $(rlocation) write it as $$(rlocation). Bazel understands $$ to be the string literal $ and the expansion results in $(rlocation) being passed as an arg instead of being expanded. $(rlocation) is then evaluated by the bash node launcher script and it calls the rlocation function in the runfiles.bash helper. For example, the templated arg $$(rlocation $(rootpath //:some_file)) is expanded by Bazel to $(rlocation ./some_file) which is then converted in bash to the absolute path of //:some_file in runfiles by the runfiles.bash helper before being passed as an argument to the program.

NB: nodejs_binary and nodejs_test will preserve the legacy behavior of $(rlocation) so users don't need to update to $$(rlocation). This may be changed in the future.

  1. Subject to predefined variables & custom variable substitutions.

Predefined “Make” variables such as $(COMPILATION_MODE) and $(TARGET_CPU) are expanded. See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_variables.

Custom variables are also expanded including variables set through the Bazel CLI with --define=SOME_VAR=SOME_VALUE. See https://docs.bazel.build/versions/master/be/make-variables.html#custom_variables.

Predefined genrule variables are not supported in this context.

Defaults to []

npm_install

Runs npm install during workspace setup.

This rule will set the environment variable BAZEL_NPM_INSTALL to ‘1’ (unless it set to another value in the environment attribute). Scripts may use to this to check if yarn is being run by the npm_install repository rule.

Usage

npm_install(name, always_hide_bazel_files, args, data, environment, included_files, manual_build_file_contents, package_json, package_lock_json, quiet, symlink_node_modules, timeout)

name

(name, mandatory): A unique name for this repository.

always_hide_bazel_files

(Boolean): Always hide Bazel build files such as BUILD and BUILD.bazelby prefixing them with_`.

This is only needed in Bazel 2.0 or earlier. We recommend upgrading to a later version to avoid the problem this works around.

Defaults to False, in which case Bazel files are not hidden when symlink_node_modules is True. In this case, the rule will report an error when there are Bazel files detected in npm packages.

Reporting the error is desirable as relying on this repository rule to hide these files does not work in the case where a user deletes their node_modules folder and manually re-creates it with yarn or npm outside of Bazel which would restore them. On a subsequent Bazel build, this repository rule does not re-run and the presence of the Bazel files leads to a build failure that looks like the following:

ERROR: /private/var/tmp/_bazel_greg/37b273501bbecefcf5ce4f3afcd7c47a/external/npm/BUILD.bazel:9:1:
Label '@npm//:node_modules/rxjs/src/AsyncSubject.ts' crosses boundary of subpackage '@npm//node_modules/rxjs/src'
(perhaps you meant to put the colon here: '@npm//node_modules/rxjs/src:AsyncSubject.ts'?)

See https://github.com/bazelbuild/rules_nodejs/issues/802 for more details.

The recommended solution is to use the @bazel/hide-bazel-files utility to hide these files. See https://github.com/bazelbuild/rules_nodejs/blob/master/packages/hide-bazel-files/README.md for installation instructions.

The alternate solution is to set always_hide_bazel_files to True which tell this rule to hide Bazel files even when symlink_node_modules is True. This means you won't need to use @bazel/hide-bazel-files utility but if you manually recreate your node_modules folder via yarn or npm outside of Bazel you may run into the above error.

Defaults to False

args

(List of strings): Arguments passed to npm install.

See npm CLI docs https://docs.npmjs.com/cli/install.html for complete list of supported arguments.

Defaults to []

data

(labels): Data files required by this rule.

If symlink_node_modules is True, this attribute is ignored since the dependency manager will run in the package.json location.

Defaults to []

environment

(Dictionary: String -> String): Environment variables to set before calling the package manager.

Defaults to {}

included_files

(List of strings): List of file extensions to be included in the npm package targets.

For example, [“.js”, “.d.ts”, “.proto”, “.json”, ""].

This option is useful to limit the number of files that are inputs to actions that depend on npm package targets. See https://github.com/bazelbuild/bazel/issues/5153.

If set to an empty list then all files are included in the package targets. If set to a list of extensions, only files with matching extensions are included in the package targets. An empty string in the list is a special string that denotes that files with no extensions such as README should be included in the package targets.

This attribute applies to both the coarse @wksp//:node_modules target as well as the fine grained targets such as @wksp//foo.

Defaults to []

manual_build_file_contents

(String): Experimental attribute that can be used to override the generated BUILD.bazel file and set its contents manually.

Can be used to work-around a bazel performance issue if the default @wksp//:node_modules target has too many files in it. See https://github.com/bazelbuild/bazel/issues/5153. If you are running into performance issues due to a large node_modules target it is recommended to switch to using fine grained npm dependencies.

Defaults to ""

package_json

(label, mandatory)

package_lock_json

(label, mandatory)

quiet

(Boolean): If stdout and stderr should be printed to the terminal.

Defaults to True

symlink_node_modules

(Boolean): Turn symlinking of node_modules on

This requires the use of Bazel 0.26.0 and the experimental managed_directories feature.

When true, the package manager will run in the package.json folder and the resulting node_modules folder will be symlinked into the external repository create by this rule.

When false, the package manager will run in the external repository created by this rule and any files other than the package.json file and the lock file that are required for it to run should be listed in the data attribute.

Defaults to True

timeout

(Integer): Maximum duration of the package manager execution in seconds.

Defaults to 3600

pkg_npm

The pkg_npm rule creates a directory containing a publishable npm artifact.

Example:

load("@build_bazel_rules_nodejs//:index.bzl", "pkg_npm")

pkg_npm(
    name = "my_package",
    srcs = ["package.json"],
    deps = [":my_typescript_lib"],
    substitutions = {"//internal/": "//"},
)

You can use a pair of // BEGIN-INTERNAL ... // END-INTERNAL comments to mark regions of files that should be elided during publishing. For example:

function doThing() {
    // BEGIN-INTERNAL
    // This is a secret internal-only comment
    doInternalOnlyThing();
    // END-INTERNAL
}

With the Bazel stamping feature, pkg_npm will replace any placeholder version in your package with the actual version control tag. See the stamping documentation

Usage:

pkg_npm yields three labels. Build the package directory using the default label:

$ bazel build :my_package
Target //:my_package up-to-date:
  bazel-out/fastbuild/bin/my_package
$ ls -R bazel-out/fastbuild/bin/my_package

Dry-run of publishing to npm, calling npm pack (it builds the package first if needed):

$ bazel run :my_package.pack
INFO: Running command line: bazel-out/fastbuild/bin/my_package.pack
my-package-name-1.2.3.tgz
$ tar -tzf my-package-name-1.2.3.tgz

Actually publish the package with npm publish (also builds first):

# Check login credentials
$ bazel run @nodejs//:npm_node_repositories who
# Publishes the package
$ bazel run :my_package.publish

You can pass arguments to npm by escaping them from Bazel using a double-hyphen, for example:

bazel run my_package.publish -- --tag=next

Usage

pkg_npm(name, deps, hide_build_files, nested_packages, node_context_data, package_name, replace_with_version, srcs, substitutions, vendor_external)

name

(name, mandatory): A unique name for this target.

deps

(labels): Other targets which produce files that should be included in the package, such as rollup_bundle

Defaults to []

hide_build_files

(Boolean): If set BUILD and BUILD.bazel files are prefixed with _ in the npm package. The default is True since npm packages that contain BUILD files don't work with yarn_install and npm_install without a post-install step that deletes or renames them.

    NB: Bazel has a change in https://github.com/bazelbuild/bazel/pull/10261
    (expected in version 2.1) that adds .bazelignore
    support for external repositories, which will make this attribute obsolete.

Defaults to True

nested_packages

(labels): Other pkg_npm rules whose content is copied into this package.

Defaults to []

node_context_data

(label): Internal use only

Defaults to @build_bazel_rules_nodejs//internal:node_context_data

package_name

(String): Optional package_name that this npm package may be imported as.

Defaults to ""

replace_with_version

(String): If set this value is replaced with the version stamp data. See the section on stamping in the README.

Defaults to "0.0.0-PLACEHOLDER"

srcs

(labels): Files inside this directory which are simply copied into the package.

Defaults to []

substitutions

(Dictionary: String -> String): Key-value pairs which are replaced in all the files while building the package.

Defaults to {}

vendor_external

(List of strings): External workspaces whose contents should be vendored into this workspace. Avoids ‘external/foo’ path segments in the resulting package.

Defaults to []

pkg_web

Assembles a web application from source files.

Usage

pkg_web(name, additional_root_paths, srcs)

name

(name, mandatory): A unique name for this target.

additional_root_paths

(List of strings): Path prefixes to strip off all srcs, in addition to the current package. Longest wins.

Defaults to []

srcs

(labels): Files which should be copied into the package

Defaults to []

yarn_install

Runs yarn install during workspace setup.

This rule will set the environment variable BAZEL_YARN_INSTALL to ‘1’ (unless it set to another value in the environment attribute). Scripts may use to this to check if yarn is being run by the yarn_install repository rule.

Usage

yarn_install(name, always_hide_bazel_files, args, data, environment, included_files, manual_build_file_contents, package_json, quiet, symlink_node_modules, timeout, use_global_yarn_cache, yarn_lock)

name

(name, mandatory): A unique name for this repository.

always_hide_bazel_files

(Boolean): Always hide Bazel build files such as BUILD and BUILD.bazelby prefixing them with_`.

This is only needed in Bazel 2.0 or earlier. We recommend upgrading to a later version to avoid the problem this works around.

Defaults to False, in which case Bazel files are not hidden when symlink_node_modules is True. In this case, the rule will report an error when there are Bazel files detected in npm packages.

Reporting the error is desirable as relying on this repository rule to hide these files does not work in the case where a user deletes their node_modules folder and manually re-creates it with yarn or npm outside of Bazel which would restore them. On a subsequent Bazel build, this repository rule does not re-run and the presence of the Bazel files leads to a build failure that looks like the following:

ERROR: /private/var/tmp/_bazel_greg/37b273501bbecefcf5ce4f3afcd7c47a/external/npm/BUILD.bazel:9:1:
Label '@npm//:node_modules/rxjs/src/AsyncSubject.ts' crosses boundary of subpackage '@npm//node_modules/rxjs/src'
(perhaps you meant to put the colon here: '@npm//node_modules/rxjs/src:AsyncSubject.ts'?)

See https://github.com/bazelbuild/rules_nodejs/issues/802 for more details.

The recommended solution is to use the @bazel/hide-bazel-files utility to hide these files. See https://github.com/bazelbuild/rules_nodejs/blob/master/packages/hide-bazel-files/README.md for installation instructions.

The alternate solution is to set always_hide_bazel_files to True which tell this rule to hide Bazel files even when symlink_node_modules is True. This means you won't need to use @bazel/hide-bazel-files utility but if you manually recreate your node_modules folder via yarn or npm outside of Bazel you may run into the above error.

Defaults to False

args

(List of strings): Arguments passed to yarn install.

See yarn CLI docs https://yarnpkg.com/en/docs/cli/install for complete list of supported arguments.

Defaults to []

data

(labels): Data files required by this rule.

If symlink_node_modules is True, this attribute is ignored since the dependency manager will run in the package.json location.

Defaults to []

environment

(Dictionary: String -> String): Environment variables to set before calling the package manager.

Defaults to {}

included_files

(List of strings): List of file extensions to be included in the npm package targets.

For example, [“.js”, “.d.ts”, “.proto”, “.json”, ""].

This option is useful to limit the number of files that are inputs to actions that depend on npm package targets. See https://github.com/bazelbuild/bazel/issues/5153.

If set to an empty list then all files are included in the package targets. If set to a list of extensions, only files with matching extensions are included in the package targets. An empty string in the list is a special string that denotes that files with no extensions such as README should be included in the package targets.

This attribute applies to both the coarse @wksp//:node_modules target as well as the fine grained targets such as @wksp//foo.

Defaults to []

manual_build_file_contents

(String): Experimental attribute that can be used to override the generated BUILD.bazel file and set its contents manually.

Can be used to work-around a bazel performance issue if the default @wksp//:node_modules target has too many files in it. See https://github.com/bazelbuild/bazel/issues/5153. If you are running into performance issues due to a large node_modules target it is recommended to switch to using fine grained npm dependencies.

Defaults to ""

package_json

(label, mandatory)

quiet

(Boolean): If stdout and stderr should be printed to the terminal.

Defaults to True

symlink_node_modules

(Boolean): Turn symlinking of node_modules on

This requires the use of Bazel 0.26.0 and the experimental managed_directories feature.

When true, the package manager will run in the package.json folder and the resulting node_modules folder will be symlinked into the external repository create by this rule.

When false, the package manager will run in the external repository created by this rule and any files other than the package.json file and the lock file that are required for it to run should be listed in the data attribute.

Defaults to True

timeout

(Integer): Maximum duration of the package manager execution in seconds.

Defaults to 3600

use_global_yarn_cache

(Boolean): Use the global yarn cache on the system.

The cache lets you avoid downloading packages multiple times. However, it can introduce non-hermeticity, and the yarn cache can have bugs.

Disabling this attribute causes every run of yarn to have a unique cache_directory.

If True, this rule will pass --mutex network to yarn to ensure that the global cache can be shared by parallelized yarn_install rules.

If False, this rule will pass --cache-folder /path/to/external/repository/__yarn_cache to yarn so that the local cache is contained within the external repository.

Defaults to True

yarn_lock

(label, mandatory)

check_bazel_version

Verify the users Bazel version is at least the given one.

This can be used in rule implementations that depend on changes in Bazel, to warn users about a mismatch between the rule and their installed Bazel version.

This should not be used in users WORKSPACE files. To locally pin your Bazel version, just create the .bazelversion file in your workspace.

Usage

check_bazel_version(minimum_bazel_version, message)

minimum_bazel_version

a string indicating the minimum version

message

optional string to print to your users, could be used to help them update

Defaults to ""

copy_to_bin

Copies a source file to bazel-bin at the same workspace-relative path path.

e.g. <workspace_root>/foo/bar/a.txt -> <bazel-bin>/foo/bar/a.txt

This is useful to populate the output folder with all files needed at runtime, even those which aren't outputs of a Bazel rule.

This way you can run a binary in the output folder (execroot or runfiles_root) without that program needing to rely on a runfiles helper library or be aware that files are divided between the source tree and the output tree.

Usage

copy_to_bin(name, srcs, kwargs)

name

Name of the rule.

srcs

A List of Labels. File(s) to to copy.

kwargs

further keyword arguments, e.g. visibility

npm_package_bin

Run an arbitrary npm package binary (e.g. a program under node_modules/.bin/*) under Bazel.

It must produce outputs. If you just want to run a program with bazel run, use the nodejs_binary rule.

This is like a genrule() except that it runs our launcher script that first links the node_modules tree before running the program.

This is a great candidate to wrap with a macro, as documented: https://docs.bazel.build/versions/master/skylark/macros.html#full-example

Usage

npm_package_bin(tool, package, package_bin, data, outs, args, output_dir, kwargs)

tool

a label for a binary to run, like @npm//terser/bin:terser. This is the longer form of package/package_bin. Note that you can also refer to a binary in your local workspace.

Defaults to None

package

an npm package whose binary to run, like “terser”. Assumes your node_modules are installed in a workspace called “npm”

Defaults to None

package_bin

the “bin” entry from package that should be run. By default package_bin is the same string as package

Defaults to None

data

similar to genrule.srcs may also include targets that produce or reference npm packages which are needed by the tool

Defaults to []

outs

similar to genrule.outs

Defaults to []

args

Command-line arguments to the tool.

Subject to 'Make variable' substitution. See https://docs.bazel.build/versions/master/be/make-variables.html.

1. Predefined source/output path substitions is applied first:

See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_label_variables.

Use $(execpath) $(execpaths) to expand labels to the execroot (where Bazel runs build actions).

Use $(rootpath) $(rootpaths) to expand labels to the runfiles path that a built binary can use
to find its dependencies.

Since npm_package_bin is used primarily for build actions, in most cases you'll want to
use $(execpath) or $(execpaths) to expand locations.

Using $(location) and $(locations) expansions is not recommended as these are a synonyms
for either $(execpath) or $(rootpath) depending on the context.

2. "Make" variables are expanded second:

Predefined "Make" variables such as $(COMPILATION_MODE) and $(TARGET_CPU) are expanded.
See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_variables.

Like genrule, you may also use some syntax sugar for locations.

- `$@`: if you have only one output file, the location of the output
- `$(@D)`: The output directory. If output_dir=False and there is only one file name in outs, this expands to the directory
    containing that file. If there are multiple files, this instead expands to the package's root directory in the genfiles
    tree, even if all generated files belong to the same subdirectory! If output_dir=True then this corresponds
    to the output directory which is the $(RULEDIR)/{target_name}.
- `$(RULEDIR)`: the root output directory of the rule, corresponding with its package
    (can be used with output_dir=True or False)

See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_genrule_variables.

Custom variables are also expanded including variables set through the Bazel CLI with --define=SOME_VAR=SOME_VALUE.
See https://docs.bazel.build/versions/master/be/make-variables.html#custom_variables.

Defaults to []

output_dir

set to True if you want the output to be a directory Exactly one of outs, output_dir may be used. If you output a directory, there can only be one output, which will be a directory named the same as the target.

Defaults to False

kwargs

params_file

Generates a UTF-8 encoded params file from a list of arguments.

Handles variable substitutions for args.

Usage

params_file(name, out, args, data, newline, kwargs)

name

Name of the rule.

out

Path of the output file, relative to this package.

args

Arguments to concatenate into a params file.

Subject to 'Make variable' substitution. See https://docs.bazel.build/versions/master/be/make-variables.html.

1. Subject to predefined source/output path variables substitutions.

The predefined variables `execpath`, `execpaths`, `rootpath`, `rootpaths`, `location`, and `locations` take
label parameters (e.g. `$(execpath //foo:bar)`) and substitute the file paths denoted by that label.

See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_label_variables for more info.

NB: This $(location) substition returns the manifest file path which differs from the *_binary & *_test
args and genrule bazel substitions. This will be fixed in a future major release.
See docs string of `expand_location_into_runfiles` macro in `internal/common/expand_into_runfiles.bzl`
for more info.

2. Subject to predefined variables & custom variable substitutions.

Predefined "Make" variables such as $(COMPILATION_MODE) and $(TARGET_CPU) are expanded.
See https://docs.bazel.build/versions/master/be/make-variables.html#predefined_variables.

Custom variables are also expanded including variables set through the Bazel CLI with --define=SOME_VAR=SOME_VALUE.
See https://docs.bazel.build/versions/master/be/make-variables.html#custom_variables.

Predefined genrule variables are not supported in this context.

Defaults to []

data

Data for $(location) expansions in args.

Defaults to []

newline

Line endings to use. One of [“auto”, “unix”, “windows”].

"auto" for platform-determined
"unix" for LF
"windows" for CRLF

Defaults to "auto"

kwargs