action.yml

name: Set up moqx build
description: >
  Install system dependencies and restore the ccache + dependency-download
  caches shared by every moqx build job. Run right after actions/checkout.

inputs:
  ccache-key:
    description: >
      ccache cache-key namespace — a short slug, distinct per build flavor so
      lanes with different flags don't share a cache (e.g. "linux", "asan",
      "conformance", "microbench"). Must be a valid actions/cache key fragment:
      no commas, so never a human-readable display name.
    required: true

runs:
  using: composite
  steps:
    # install-system-deps.sh elevates its own package-manager calls, so the same
    # invocation serves both runner families.
    - name: Install system dependencies
      shell: bash
      run: |
        scripts/install-system-deps.sh
        if [[ "$(uname)" == "Darwin" ]]; then
          brew install coreutils
          echo "/opt/homebrew/opt/coreutils/libexec/gnubin" >> "$GITHUB_PATH"
        fi

    # The moqx CMakeLists routes the compiler through ccache automatically when
    # it is installed (install-system-deps.sh installs it).
    - name: Cache ccache
      uses: actions/cache@v5
      with:
        path: ~/.cache/ccache
        key: ccache-${{ runner.os }}-${{ inputs.ccache-key }}-${{ github.sha }}
        restore-keys: |
          ccache-${{ runner.os }}-${{ inputs.ccache-key }}-

    # The prebuilt tarball is named for the host's *distro* release, so the key
    # needs that granularity: on runner.os alone a bookworm self-hosted box and
    # an ubuntu-22.04 runner collide, and the loser re-downloads every run.
    - name: Derive the dependency-cache platform key
      id: depkey
      shell: bash
      run: |
        if [[ "$(uname)" == "Darwin" ]]; then
          plat="macos-$(sw_vers -productVersion | cut -d. -f1)"
        else
          plat="$(. /etc/os-release && echo "${ID}-${VERSION_ID}")"
        fi
        echo "plat=${plat}-$(uname -m)" >> "$GITHUB_OUTPUT"

    # One shared fetch cache for CPM sources and the prebuilt moxygen install,
    # ~680 MB of downloads per configure otherwise, content-keyed on the pins.
    - name: Cache dependency downloads
      uses: actions/cache@v5
      with:
        path: ~/.cache/moqx
        key: deps-${{ steps.depkey.outputs.plat }}-${{ hashFiles('cmake/dependencies.cmake') }}
        # actions/cache saves only at job end, so a pin bump misses the exact key
        # in all ~11 concurrent jobs. The prefix starts them from the previous
        # tree and fetches the delta.
        restore-keys: |
          deps-${{ steps.depkey.outputs.plat }}-

    # Restoring by prefix carries every previously pinned rev's install tree
    # along (~320 MB each), so drop the unusable ones before the save step
    # re-uploads them. The CPM clones accumulate too, but are far smaller.
    - name: Prune superseded prebuilt installs
      shell: bash
      run: |
        cache="$HOME/.cache/moqx"
        [ -d "$cache" ] || exit 0
        rev="$(cmake -DPIN=MOXYGEN_REV -P cmake/print-pin.cmake)"
        for d in "$cache"/moxygen-*; do
          case "${d##*/}" in
            "moxygen-${rev:0:12}-"*)  ;;                     # this run's install
            moxygen-????????????-*)   rm -rf "$d" ;;         # a superseded pin's
          esac
        done
        rm -rf "$cache/downloads"

    - name: Route the dependency and ccache dirs through the caches
      shell: bash
      run: |
        # The root only; cmake/DepsCache.cmake puts the CPM clones under it.
        echo "MOQX_DEPS_CACHE=$HOME/.cache/moqx" >> "$GITHUB_ENV"
        # Pin ccache's dir to the cached path; its own default is platform-dependent.
        echo "CCACHE_DIR=$HOME/.cache/ccache" >> "$GITHUB_ENV"
        # GITHUB_TOKEN stays off $GITHUB_ENV, which would hand it to every later
        # step in the job, ctest among them — and ctest runs the relay and the
        # shell integration tests. The configure step sets it for its one API read.