Cache deno modules

[jacque006]

It would be nice if this action had a way to cache deno modules that had been downloaded in previous runs, similarly to https://github.com/actions/setup-node#caching-global-packages-data

The cache looks like it is easy enough to find https://deno.land/manual/linking_to_external_code#linking-to-third-party-code . However, I'm unsure what the key/hash for lookup and download would be to:

• Determine if a module had changed in any file.
• Lookup existing module caches.

This part is easier with a NodeJS package manager such as npm or yarn as you can just use a hash of the lockfile.

[jespertheend]

I bet there's some way to do this using https://github.com/actions/cache, but I'm not sure what would be the right paths for hashFiles() and path

[GJZwiers]

I bet there's some way to do this using https://github.com/actions/cache, but I'm not sure what would be the right paths for hashFiles() and path

It can be achieved by pointing path to the location of DENO_DIR and calling hashFiles() on the lockfile that is written with deno cache --lock=<file> --lock-write. For example:

env:
  DENO_DIR: my_cache_directory

steps:
  - name: Cache Deno dependencies 
    uses: actions/cache@v2
    with:
      path: ${{ env.DENO_DIR }}
      key: ${{ hashFiles('lock.json') }}

Having an option in setup_deno to cache could be useful, although there is perhaps more diversity in what lockfile names people use compared to Node where it is almost always package-lock.json, npm-shrinkwrap.json or yarn.lock.

[csvn]

This would be greatly appreciated. It would streamline action setup a lot to not have to manually setup actions/cache.

[joshdales]

Just discovered that there are also examples in actions/cache of setting it up with Deno https://github.com/actions/cache/blob/main/examples.md#deno. Thought I would share in case others come looking for more examples.

Though I agree with others that it would be nice if it was part of the deno action.

[csvn]

I've created a PR for this now: #89. Unfortunately, @actions/cache is a package with a lot of dependencies, and the checked in /node_modules would become huge if it's just installed as-is.

I've opened the PR to get feedback. Perhaps the Deno team will just accept installing the dependencies and pushing them to the branch, or it might be required to add a build-step (similar to @actions/setup-node) to bundle everything into one file.

Hopefully, it should be possible to do something like below if the PR get's merged, and save a ton of boilerplate.

# Before
env:
  DENO_DIR: ${{ github.workspace }}/.deno

      - uses: denoland/setup-deno@v2
      - uses: actions/cache/restore@v4
        id: cache
        with:
          path: ${{ env.DENO_DIR }}
          key: cache-${{ runner.os }}-test-${{ hashFiles('deno.lock') }}
          restore-keys: cache-${{ runner.os }}
      - run: deno run -A npm:cowsay Hello!
      - uses: actions/cache/save@v4
        with:
          path: ${{ env.DENO_DIR }}
          key: ${{ steps.cache.outputs.cache-primary-key }}

# After
      - uses: denoland/setup-deno@v2
        with:
          cache: true
          cache-hash: ${{ hashFiles('deno.lock') }}
      - run: deno run -A npm:cowsay Hello!