Paketo Buildpack for Node Engine

gcr.io/paketo-buildpacks/node-engine

The Node Engine CNB provides the Node binary distribution. The buildpack installs the Node binary distribution onto the $PATH which makes it available for subsequent buildpacks and in the final running container. Examples of buildpacks that might use the Node binary distribution are the NPM CNB and Yarn Install CNB

Version support

node-engine will include Node.js versions which are supported as LTS in the community as well as the active current release. When a Node.js version goes End of Life (EOL) in the community it may be removed from node-engine any time after that.

For more information on what versions are LTS and current refer to Node.js projects Release Schedule.

Integration

The Node Engine CNB provides node and npm as dependencies. Downstream buildpacks, like Yarn Install CNB or NPM CNB, can require the node dependency by generating a Build Plan TOML file that looks like the following:

[[requires]]

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

  # The version of the Node Engine dependency is not required. In the case it
  # is not specified, the buildpack will provide the default version, which can
  # be seen in the buildpack.toml file.
  # If you wish to request a specific version, the buildpack supports
  # specifying a semver constraint in the form of "15.*", "15.14.*", or even
  # "15.14.0".
  version = "15.14.0"

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

    # Setting the build flag to true will ensure that the Node Engine
    # depdendency is available on the $PATH for subsequent buildpacks during
    # their build phase. If you are writing a buildpack that needs to run Node
    # during its build process, this flag should be set to true.
    build = true

    # Setting the launch flag to true will ensure that the Node Engine
    # dependency is available on the $PATH for the running application. If you are
    # writing an application that needs to run node at runtime, this flag should
    # be set to true.
    launch = true

Or they can require both node and npm using a Build Plan that looks like the following:

[[requires]]

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

  # The version of the Node Engine dependency is not required. In the case it
  # is not specified, the buildpack will provide the default version, which can
  # be seen in the buildpack.toml file.
  # If you wish to request a specific version, the buildpack supports
  # specifying a semver constraint in the form of "15.*", "15.14.*", or even
  # "15.14.0".
  version = "15.14.0"

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

    # Setting the build flag to true will ensure that the Node Engine
    # depdendency is available on the $PATH for subsequent buildpacks during
    # their build phase. If you are writing a buildpack that needs to run Node
    # during its build process, this flag should be set to true.
    build = true

    # Setting the launch flag to true will ensure that the Node Engine
    # dependency is available on the $PATH for the running application. If you are
    # writing an application that needs to run node at runtime, this flag should
    # be set to true.
    launch = true

[[requires]]

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

Usage

To package this buildpack for consumption:

$ ./scripts/package.sh --version <version-number>

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

Configurations

Specifying a Node version

To specify the version of the Node that is installed, set the $BP_NODE_VERSION environment variable at build time either directly (ex. pack build my-app --env BP_NODE_VERSION=~15) or through a project.toml file

$BP_NODE_VERSION="~15"

You can also specify a node version via an .nvmrc or .node-version file, also at the application directory root.

Enabling memory optimization

To specify the use of memory optimization, set the $BP_NODE_OPTIMIZE_MEMORY environment variable at build time either directly (ex. pack build my-app --env BP_NODE_OPTIMIZE_MEMORY=true) or through a project.toml file

$BP_NODE_OPTIMIZE_MEMORY="true"

Specifying a project path

To specify a project subdirectory to be used as the root of the app, please use the BP_NODE_PROJECT_PATH environment variable at build time either directly (ex. pack build my-app --env BP_NODE_PROJECT_PATH=./src/my-app) or through a project.toml file. This could be useful if your app is a part of a monorepo.

Enabling Inspector for Remote Debugging

To enable the Inspector set the BPL_DEBUG_ENABLED environment variable at launch time. Optionally, you can specify the BPL_DEBUG_PORT environment variable to use a specific port.

$BPL_DEBUG_ENABLED="true"
$BPL_DEBUG_PORT="9009"

For more information on debugging, see Official Documentation

Run Tests

To run all unit tests, run:

./scripts/unit.sh

To run all integration tests, run:

/scripts/integration.sh