PIP Cloud Native Buildpack

The Paketo Buildpack for Pip is a Cloud Native Buildpack that installs pip into a layer and places it on the PATH.

The buildpack is published for consumption at gcr.io/paketo-buildpacks/pip and paketobuildpacks/pip.

Behavior

This buildpack always participates.

The buildpack will do the following:

• At build time:
  • Contributes the pip binary to a layer
  • Prepends the pip layer to the PYTHONPATH
  • Adds the newly installed pip location to PATH
• At run time:
  • Does nothing

Configuration

Environment Variable	Description
$BP_PIP_VERSION	Configure the version of pip to install. Buildpack releases (and the pip versions for each release) can be found here.

Note that Pip releases are of the form X.Y instead of X.Y.0, so providing X.Y will attempt to match that exact version. Providing X.Y.Z will select the exact patch version, and providing X.Y.* or ~X.Y will select the latest patch version.

Integration

The Pip CNB provides pip as a dependency. Downstream buildpacks can require the pip dependency by generating a Build Plan TOML file that looks like the following:

[[requires]]

  # The name of the Pip dependency is "pip". This value is considered
  # part of the public API for the buildpack and will not change without a plan
  # for deprecation.
  name = "pip"

  # The version of the Pip dependency is not required. In the case it
  # is not specified, the buildpack will select the latest supported version in
  # the buildpack.toml.
  # If you wish to request a specific version, the buildpack supports
  # specifying a semver constraint in the form of "21.*", "21.0.*", or even
  # "21.0.1".
  version = "21.0.1"

  # The Pip buildpack supports some non-required metadata options.
  [requires.metadata]

    # Setting the build flag to true will ensure that the Pip dependency is
    # available on the $PATH, and the $PYTHONPATH contains the path to pip for
    # subsequent buildpacks during their build phase. If you are writing a
    # buildpack that needs to run Pip during its build process, this flag should
    # be set to true.
    build = true

    # Setting the launch flag to true will ensure that the Pip
    # dependency is available on the $PATH, and the $PYTHONPATH contains the
    # path to pip for the running application. If you are writing an
    # application that needs to run Pip at runtime, this flag should be set to
    # true.
    launch = true

Usage

To package this buildpack for consumption:

$ ./scripts/package.sh --version x.x.x

This will create a buildpackage.cnb file under the build directory which you can use to build your app as follows: pack build <app-name> -p <path-to-app> -b build/buildpackage.cnb -b <other-buildpacks..>.

To run the unit and integration tests for this buildpack:

$ ./scripts/unit.sh && ./scripts/integration.sh