Add PROJECT_PATH environment variable

[S-Coyle]

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Motivation

For a variety of reasons, many projects don't contain their Cargo.toml file in their root directory, or they have multiple sub-projects each with their own Cargo.tomls. Would it be possible to make the project path configurable? That way the community would benefit from being able to run from a specified path.
We've added this action to a few of our projects and I'm in the process of expanding that to others as it works well, but I've hit this issue which seems to block me from using it in projects such as here and only the root directory `Cargo.toml in this repo here EDIT: was mistaken about this particular linked repo being an example.

Workflow example

name: Security audit
on:
  schedule:
    - cron: '0 0 * * *'
      
  paths: 
jobs:
  audit:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v1
      - uses: actions-rs/audit-check@v1
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
        env:
          PROJECT_PATH: ./my_sub_folder

Additional context

As far as I'm aware there's no way around this at the moment. Been looking for workarounds to this issue I'm facing and found the working-directory option here but turns out it can only be used with run and not with uses.
Found a PR here which seems to have resolved this in another action, hoping something similar would work with audit-check.

[colin-grapl]

Same issue here - we use a cargo workspace.

[fenollp]

Same -- see also actions-rs/cargo#59

[mortendahl]

Same, this would be useful

[martin-g]

Related to actions-rs/cargo#86

The best would be if it takes into account the current working directory:

defaults:
  run:
    working-directory: lang/rust

See https://docs.github.com/en/actions/reference/workflow-syntax-for-github-actions#defaultsrun

[jblachly]

We need this for our monorepo.

See also #194

Ideally, I would suggest letting cargo do the work; it already has a --manifest-path <path/to/Cargo.toml> argument.

In fact, other actions in the actions-rs repo permit this via

with:
  args: --manifest-path mypath/Cargo.toml

[lsunsi]

I also hit this particular wall while integrating with my project. Posting to subscribe on further results!

[fzyzcjy]

any updates?

[georglauterbach]

I need this as well. This issue seems to have become stale, but it is quite important. Not every repository has the Rust code / Cargo.toml directly in the repository root.