`docker.io/paketocommunity/cargo`

The Rust Cargo Buildpack is a Cloud Native Buildpack that builds Rust applications using Cargo.

This buildpack is designed to work in collaboration with the Rust Dist CNB or Rustup CNB buildpacks which provide the actual Rust and Cargo binaries used by this buildpack.

Behavior

If all of these conditions are met:

<APPLICATION_ROOT>/Cargo.toml exists
<APPLICATION_ROOT>/Cargo.lock exists

The buildpack will do the following:

Requests that Rust and Cargo be installed
Uses CARGO_HOME to locate Cargo & tools
Symlinks <APPLICATION_ROOT/target> to a cache layer, so that build artifacts are cached
Reads workspace members out of Cargo.toml
For each workspace member, it executes cargo install to build and install binaries. Binaries are installed to a layer marked with cache
All source code is removed from /workspace
The application binary is copied from the cache layer to /workspace
Cleans CARGO_HOME as described in the Cargo book

Configuration

Environment Variable	Description
`$BP_CARGO_INSTALL_ARGS`	Additional arguments for `cargo install`. By default, the buildpack will run `cargo install --color=never --root=<destination layer> --path=<path-to-member>` for each workspace member. See more details below.
`$BP_CARGO_WORKSPACE_MEMBERS`	A comma delimited list of the workspace package names (this is the package name in the member's `Cargo.toml`, not what is in the workspace's `Cargo.toml`'s member list) to install. If the project is not using workspaces, this is not used. By default, for projects with a workspace, the buildpack will build all members in a workspace. See more details below.
`$BP_CARGO_EXCLUDE_FOLDERS`	A comma delimited list of the top-level folders that should not be deleted, which means they will persist through to the generated image. This only applies to top level folders. You only need the folder name, not a full path.

`BP_CARGO_INSTALL_ARGS`

Additional arguments for cargo install. Any additional arguments specified, are specified for each invocation of cargo install. The buildpack will execute cargo install once for each workspace member. If you're not using a workspace, then it executes a single time.

A few examples of what you can specify:

--path=./todo to build a single member in a folder called ./todo if you have a non-traditional folder structure
--bins to build all binaries in your project
--bin=foo to specifically build the foo binary when multiple binaries are present
-v to get more verbose output from cargo install
--frozen or --locked or customizing how Cargo will use the Cargo.lock file
--offline for preventing Cargo from trying to access the Internet
or any other valid arguments that can be passed to cargo install

You may not set --color and you may not set --root. These are fixed by the buildpack in order to make output look correct and to ensure that binaries are installed into the proper location.

`BP_CARGO_WORKSPACE_MEMBERS`

This option may be used in conjunction with BP_CARGO_INSTALL_ARGS, however you may not set --path in BP_CARGO_INSTALL_ARGS when also setting BP_CARGO_WORKSPACE_MEMBERS, as the buildpack will control --path when building workspace members.

In summary:

Use BP_CARGO_INSTALL_ARGS and --path to build one specific member of a workspace.
Use BP_CARGO_INSTALL_ARGS to specify non---path arguments to cargo install
Use BP_CARGO_WORKSPACE_MEMBERS to specify one or more workspace members to build (using BP_CARGO_WORKSPACE_MEMBERS with only one member has identical behavior to BP_CARGO_INSTALL_ARGS and --path)
Don't set either BP_CARGO_INSTALL_ARGS and --path, or BP_CARGO_WORKSPACE_MEMBERS and the buildpack will iterate through and build all of the members in workspace.

Usage

In general, you probably want the rust CNB instead.

If you want to use this particular CNB directly, the easiest way is via image. Run pack build -b paketo-community/cargo:<version> ....

License

This buildpack is released under version 2.0 of the Apache License.

Shashankft9/cargo

docker.io/paketocommunity/cargo