Workspace Rules
Workspace rules are used to pull in external dependencies, typically source code located outside the main repository.
Note: besides the native workspace rules, Bazel also embeds various Starlark workspace rules, in particular those to deal with git repositories or archives hosted on the web.
bind
bind(name, actual, compatible_with, deprecation, distribs, features, licenses, restricted_to, tags, testonly, visibility)
Warning: use of bind() is not recommended. See "Consider removing bind" for a long
discussion of its issues and alternatives.
Warning: select() cannot be used in bind(). See the Configurable Attributes FAQ for
details.
Gives a target an alias in the //external package.
The //external package is not a "normal" package: there is no external/ directory,
so it can be thought of as a "virtual package" that contains all bound targets.
Examples
To give a target an alias, bind it in the WORKSPACE file. For example,
suppose there is a java_library target called
//third_party/javacc-v2. This can be aliased by adding the following to the
WORKSPACE file:
bind(
name = "javacc-latest",
actual = "//third_party/javacc-v2",
)
Now targets can depend on //external:javacc-latest instead of
//third_party/javacc-v2. If javacc-v3 is released, the bind rule can be
updated and all of the BUILD files depending on //external:javacc-latest will now
depend on javacc-v3 without needing to be edited.
Bind can also be used to make targets in external repositories available to your workspace.
For example, if there is a remote repository named @my-ssl imported in the
WORKSPACE file and it has a cc_library target //src:openssl-lib, you can
create an alias for this target using bind:
bind(
name = "openssl",
actual = "@my-ssl//src:openssl-lib",
)
Then, in a BUILD file in your workspace, the bound target can be used as follows:
cc_library(
name = "sign-in",
srcs = ["sign_in.cc"],
hdrs = ["sign_in.h"],
deps = ["//external:openssl"],
)
Within sign_in.cc and sign_in.h, the header files exposed by
//external:openssl can be referred to using their path relative to their repository
root. For example, if the rule definition for @my-ssl//src:openssl-lib looks like
this:
cc_library(
name = "openssl-lib",
srcs = ["openssl.cc"],
hdrs = ["openssl.h"],
)
Then sign_in.cc's includes might look like this:
#include "sign_in.h" #include "src/openssl.h"
Arguments
| Attributes | |
|---|---|
name |
A unique name for this target. |
actual
|
This target must exist, but can be any type of rule (including bind). If this attribute is omitted, rules referring to this target in |
local_repository
local_repository(name, path)
Allows targets from a local directory to be bound. This means that the current repository can use targets defined in this other directory. See the bind section for more details.
Examples
Suppose the current repository is a chat client, rooted at the directory ~/chat-app. It
would like to use an SSL library which is defined in a different repository: ~/ssl. The
SSL library has a target //src:openssl-lib.
The user can add a dependency on this target by adding the following lines to ~/chat-app/WORKSPACE:
local_repository(
name = "my-ssl",
path = "/home/user/ssl",
)
Targets would specify @my-ssl//src:openssl-lib as a dependency to depend on this
library.
Arguments
| Attributes | |
|---|---|
name |
A unique name for this target. |
path
|
This must be a path to the directory containing the repository's WORKSPACE file. The path can be either absolute or relative to the main repository's WORKSPACE file. |
maven_jar
maven_jar(name, artifact, repository, server, sha1, sha1_src, sha256, sha256_src)
This rule is DEPRECATED. Instead, use [rules_jvm_external](https://github.com/bazelbuild/rules_jvm_external) to manage your Maven dependencies.
Downloads a jar from Maven and makes it available to be used as a Java dependency.
Naming
Note that the maven_jar name is used as a repository name, so it is limited by the rules
governing workspace names: it cannot contain dashes nor dots (see
the documentation on workspace
names for the exact specification). By convention, maven_jar names should match the artifact
name, replacing illegal characters with underscores and leaving off the version. For example, a
rule with artifact = "org.apache.commons:commons-lang3:3.4" should have
name = "org_apache_commons_commons_lang3".
Examples
Suppose that the current repostory contains a java_library target that needs to depend on Guava. Using Maven, this dependency would be defined in the pom.xml file as:
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>18.0</version>
</dependency>
With Bazel, add the following lines to the WORKSPACE file:
maven_jar(
name = "com_google_guava_guava",
artifact = "com.google.guava:guava:18.0",
sha1 = "cce0823396aa693798f8882e64213b1772032b09",
sha1_src = "ad97fe8faaf01a3d3faacecd58e8fa6e78a973ca",
)
Targets can specify @com_google_guava_guava//jar as a dependency to depend on this
jar.
Arguments
| Attributes | |
|---|---|
name |
A unique name for this target. |
artifact
|
These descriptions are of the form <groupId>:<artifactId>:<version>, see the documentation below for an example. |
repository
|
Either this or |
server
|
Either this or |
sha1
|
If the downloaded jar does not match this hash, Bazel will error out. It is a security
risk to download a file without verifying cryptographic secure hash. Note that SHA-1 is
no longer considered a secure cryptographic hash function, but specifying the hash is
still marginally better than no check at all. This attribute is kept here for legacy support
purposes. Please either use the 'sha256' attribute or migrate to
|
sha1_src
|
If the downloaded source jar does not match this hash, Bazel will error out. It is a security risk to download a file without verifying cryptographic secure hash. |
sha256
|
If the downloaded jar does not match this hash, Bazel will error out. It is a security risk to download a file without verifying cryptographic secure hash. |
sha256_src
|
If the downloaded source jar does not match this hash, Bazel will error out. It is a security risk to download a file without verifying cryptographic secure hash. |
maven_server
maven_server(name, settings_file, url)
This rule is DEPRECATED. Instead, use [rules_jvm_external](https://github.com/bazelbuild/rules_jvm_external) to manage your Maven dependencies.
How to access a Maven repository.
This is a combination of a <repository> definition from a pom.xml file and a <server> definition from a settings.xml file.
Using maven_server
maven_jar rules can specify the name of a maven_server in their
server field. For example, suppose we have the following WORKSPACE file:
maven_jar(
name = "junit",
artifact = "junit:junit-dep:4.10",
server = "my_server",
)
maven_server(
name = "my_server",
url = "http://intranet.mycorp.net",
)
This specifies that junit should be downloaded from http://intranet.mycorp.net using the
authentication information found in ~/.m2/settings.xml (specifically, the settings
for the server with the id my_server).
Specifying a default server
If you create a maven_server with the name "default" it will be
used for any maven_jar that does not specify a server nor
repository. If there is no maven_server named default, the
default will be fetching from Maven Central with no authentication enabled.
Arguments
| Attributes | |
|---|---|
name |
A unique name for this target. |
settings_file
|
$M2_HOME/conf/settings.xml for the global settings and
$HOME/.m2/settings.xml for the user settings.
|
url
|
For example, Maven Central (which is the default and does not need to be defined) would
be specified as |
new_local_repository
new_local_repository(name, build_file, build_file_content, path, workspace_file, workspace_file_content)
Allows a local directory to be turned into a Bazel repository. This means that the current repository can define and use targets from anywhere on the filesystem.
This rule creates a Bazel repository by creating a WORKSPACE file and subdirectory containing
symlinks to the BUILD file and path given. The build file should create targets relative to the
path. For directories that already contain a WORKSPACE file and a BUILD file, the
local_repository rule can be used.
Examples
Suppose the current repository is a chat client, rooted at the directory ~/chat-app. It would like to use an SSL library which is defined in a different directory: ~/ssl.
The user can add a dependency by creating a BUILD file for the SSL library (~/chat-app/BUILD.my-ssl) containing:
java_library(
name = "openssl",
srcs = glob(['*.java'])
visibility = ["//visibility:public"],
)
Then they can add the following lines to ~/chat-app/WORKSPACE:
new_local_repository(
name = "my-ssl",
path = "/home/user/ssl",
build_file = "BUILD.my-ssl",
)
This will create a @my-ssl repository that symlinks to /home/user/ssl.
Targets can depend on this library by adding @my-ssl//:openssl to a target's
dependencies.
You can also use new_local_repository to include single files, not just
directories. For example, suppose you had a jar file at /home/username/Downloads/piano.jar. You
could add just that file to your build by adding the following to your WORKSPACE file:
new_local_repository(
name = "piano",
path = "/home/username/Downloads/piano.jar",
build_file = "BUILD.piano",
)
And creating the following BUILD.piano file:
java_import(
name = "play-music",
jars = ["piano.jar"],
visibility = ["//visibility:public"],
)
Then targets can depend on @piano//:play-music to use piano.jar.
Arguments
| Attributes | |
|---|---|
name |
A unique name for this target. |
build_file
|
Either build_file or build_file_content must be specified. This attribute is a label relative to the main workspace. The file does not need to be named BUILD, but can be. (Something like BUILD.new-repo-name may work well for distinguishing it from the repository's actual BUILD files.) |
build_file_content
|
Either build_file or build_file_content must be specified. |
path
|
This must be an absolute path to an existing file or a directory. |
workspace_file
|
Either workspace_file or workspace_file_content can be specified, but not both. This attribute is a label relative to the main workspace. The file does not need to be named WORKSPACE, but can be. (Something like WORKSPACE.new-repo-name may work well for distinguishing it from the repository's actual WORKSPACE files.) |
workspace_file_content
|
Either workspace_file or workspace_file_content can be specified, but not both. |
xcode_config
xcode_config(name, deprecation, distribs, features, licenses, tags, testonly, visibility)
A single target of this rule can be referenced by the --xcode_version_config build
flag to translate the --xcode_version flag into an accepted official xcode version.
This allows selection of a an official xcode version from a number of registered aliases.
Arguments
| Attributes | |
|---|---|
name |
A unique name for this target. |
xcode_version
xcode_version(name, default_ios_sdk_version, default_macos_sdk_version, default_tvos_sdk_version, default_watchos_sdk_version, deprecation, distribs, features, is_local, licenses, tags, testonly, version, visibility)
Represents a single official xcode version with acceptable aliases for that xcode version.
See the xcode_config rule.
Arguments
| Attributes | |
|---|---|
name |
A unique name for this target. |
default_ios_sdk_version
|
ios_sdk_version build flag will override the value specified here.
|
default_macos_sdk_version
|
macos_sdk_version build flag will override the value specified here.
|
default_tvos_sdk_version
|
tvos_sdk_version build flag will override the value specified here.
|
default_watchos_sdk_version
|
watchos_sdk_version build flag will override the value specified here.
|
is_local
|
|
version
|
|