# Copyright 2017 The Bazel Authors. All rights reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Import pip requirements into Bazel.""" load("//python/pip_install:pip_repository.bzl", "pip_repository", _package_annotation = "package_annotation") load("//python/pip_install:repositories.bzl", "pip_install_dependencies") load("//python/pip_install:requirements.bzl", _compile_pip_requirements = "compile_pip_requirements") compile_pip_requirements = _compile_pip_requirements package_annotation = _package_annotation def pip_install(requirements = None, name = "pip", **kwargs): """Accepts a `requirements.txt` file and installs the dependencies listed within. Those dependencies become available in a generated `requirements.bzl` file. This macro wraps the [`pip_repository`](./pip_repository.md) rule that invokes `pip`. In your WORKSPACE file: ```python pip_install( requirements = ":requirements.txt", ) ``` You can then reference installed dependencies from a `BUILD` file with: ```python load("@pip//:requirements.bzl", "requirement") py_library( name = "bar", ... deps = [ "//my/other:dep", requirement("requests"), requirement("numpy"), ], ) ``` > Note that this convenience comes with a cost. > Analysis of any BUILD file which loads the requirements helper in this way will > cause an eager-fetch of all the pip dependencies, > even if no python targets are requested to be built. > In a multi-language repo, this may cause developers to fetch dependencies they don't need, > so consider using the long form for dependencies if this happens. In addition to the `requirement` macro, which is used to access the `py_library` target generated from a package's wheel, the generated `requirements.bzl` file contains functionality for exposing [entry points][whl_ep] as `py_binary` targets. [whl_ep]: https://packaging.python.org/specifications/entry-points/ ```python load("@pip_deps//:requirements.bzl", "entry_point") alias( name = "pip-compile", actual = entry_point( pkg = "pip-tools", script = "pip-compile", ), ) ``` Note that for packages whose name and script are the same, only the name of the package is needed when calling the `entry_point` macro. ```python load("@pip_deps//:requirements.bzl", "entry_point") alias( name = "flake8", actual = entry_point("flake8"), ) ``` Args: requirements (Label): A 'requirements.txt' pip requirements file. name (str, optional): A unique name for the created external repository (default 'pip'). **kwargs (dict): Additional arguments to the [`pip_repository`](./pip_repository.md) repository rule. """ # Just in case our dependencies weren't already fetched pip_install_dependencies() pip_repository( name = name, requirements = requirements, repo_prefix = "pypi__", **kwargs ) def pip_parse(requirements_lock, name = "pip_parsed_deps", **kwargs): """Accepts a locked/compiled requirements file and installs the dependencies listed within. Those dependencies become available in a generated `requirements.bzl` file. You can instead check this `requirements.bzl` file into your repo, see the "vendoring" section below. This macro wraps the [`pip_repository`](./pip_repository.md) rule that invokes `pip`, with `incremental` set. In your WORKSPACE file: ```python load("@rules_python//python:pip.bzl", "pip_parse") pip_parse( name = "pip_deps", requirements_lock = ":requirements.txt", ) load("@pip_deps//:requirements.bzl", "install_deps") install_deps() ``` You can then reference installed dependencies from a `BUILD` file with: ```python load("@pip_deps//:requirements.bzl", "requirement") py_library( name = "bar", ... deps = [ "//my/other:dep", requirement("requests"), requirement("numpy"), ], ) ``` In addition to the `requirement` macro, which is used to access the generated `py_library` target generated from a package's wheel, The generated `requirements.bzl` file contains functionality for exposing [entry points][whl_ep] as `py_binary` targets as well. [whl_ep]: https://packaging.python.org/specifications/entry-points/ ```python load("@pip_deps//:requirements.bzl", "entry_point") alias( name = "pip-compile", actual = entry_point( pkg = "pip-tools", script = "pip-compile", ), ) ``` Note that for packages whose name and script are the same, only the name of the package is needed when calling the `entry_point` macro. ```python load("@pip_deps//:requirements.bzl", "entry_point") alias( name = "flake8", actual = entry_point("flake8"), ) ``` ## Vendoring the requirements.bzl file In some cases you may not want to generate the requirements.bzl file as a repository rule while Bazel is fetching dependencies. For example, if you produce a reusable Bazel module such as a ruleset, you may want to include the requirements.bzl file rather than make your users install the WORKSPACE setup to generate it. See https://github.com/bazelbuild/rules_python/issues/608 This is the same workflow as Gazelle, which creates `go_repository` rules with [`update-repos`](https://github.com/bazelbuild/bazel-gazelle#update-repos) To do this, use the "write to source file" pattern documented in https://blog.aspect.dev/bazel-can-write-to-the-source-folder to put a copy of the generated requirements.bzl into your project. Then load the requirements.bzl file directly rather than from the generated repository. See the example in rules_python/examples/pip_parse_vendored. Args: requirements_lock (Label): A fully resolved 'requirements.txt' pip requirement file containing the transitive set of your dependencies. If this file is passed instead of 'requirements' no resolve will take place and pip_repository will create individual repositories for each of your dependencies so that wheels are fetched/built only for the targets specified by 'build/run/test'. Note that if your lockfile is platform-dependent, you can use the `requirements_[platform]` attributes. name (str, optional): The name of the generated repository. The generated repositories containing each requirement will be of the form _. **kwargs (dict): Additional arguments to the [`pip_repository`](./pip_repository.md) repository rule. """ # Just in case our dependencies weren't already fetched pip_install_dependencies() pip_repository( name = name, requirements_lock = requirements_lock, repo_prefix = "{}_".format(name), incremental = True, **kwargs )