distrib-cache-maintenance.yml

name: Distrib Cache Maintenance

on:
  # Regular refresh to prevent GitHub's 7-day eviction policy
  schedule:
    - cron: '0 4 * * 1,4'  # Monday and Thursday at 4 AM
  workflow_dispatch:
    inputs:
      max_age_days:
        description: 'Maximum age of files to keep (days)'
        required: false
        default: '180'
        type: string
      dry_run:
        description: 'Dry run mode (no deletions)'
        required: false
        default: false
        type: boolean

jobs:
  maintain-distrib-cache:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v6

      - name: Restore distrib cache
        id: cache-restore
        uses: actions/cache/restore@v5
        with:
          path: distrib
          # Use a placeholder key that will never match for the exact key,
          # forcing GitHub to use restore-keys to find the best available cache
          key: distrib-placeholder-${{ github.run_id }}
          restore-keys: |
            distrib-

      - name: Display cache status
        run: |
          if [ "${{ steps.cache-restore.outputs.cache-hit }}" = "true" ]; then
            echo "Cache restored successfully"
          else
            echo "No cache found or partial restore"
          fi

          echo ""
          echo "Current distrib cache status:"
          if [ -d "distrib" ]; then
            FILE_COUNT=$(find distrib -type f | wc -l)
            TOTAL_SIZE=$(du -sh distrib 2>/dev/null | cut -f1 || echo "0")
            echo "  Files: $FILE_COUNT"
            echo "  Size: $TOTAL_SIZE"
          else
            echo "  (empty)"
            mkdir -p distrib
          fi

      - name: Clean old files from distrib
        env:
          MAX_AGE_DAYS: ${{ github.event.inputs.max_age_days || '180' }}
          DRY_RUN: ${{ github.event.inputs.dry_run || 'false' }}
        run: |
          echo "Cleaning files older than $MAX_AGE_DAYS days"
          echo ""

          if [ ! -d "distrib" ] || [ -z "$(ls -A distrib 2>/dev/null)" ]; then
            echo "Distrib cache is empty, nothing to clean"
            exit 0
          fi

          # Remove corrupted/invalid files marked as .wrong by checksum verification
          WRONG_FILES=$(find distrib -type f -name "*.wrong" 2>/dev/null || true)
          if [ -n "$WRONG_FILES" ]; then
            WRONG_COUNT=$(echo "$WRONG_FILES" | wc -l)
            echo "Found $WRONG_COUNT corrupted file(s) marked as .wrong"
            if [ "$DRY_RUN" = "true" ]; then
              echo "[DRY RUN] Would delete $WRONG_COUNT .wrong file(s)"
              echo "Sample files (first 5):"
              echo "$WRONG_FILES" | head -5
            else
              echo "$WRONG_FILES" | xargs rm -f
              echo "Deleted $WRONG_COUNT .wrong file(s)"
            fi
            echo ""
          fi

          # Find files not modified for more than MAX_AGE_DAYS
          OLD_FILES=$(find distrib -type f -mtime +${MAX_AGE_DAYS} 2>/dev/null || true)

          if [ -z "$OLD_FILES" ]; then
            echo "No obsolete files found"
            exit 0
          fi

          OLD_COUNT=$(echo "$OLD_FILES" | wc -l)
          OLD_SIZE=$(echo "$OLD_FILES" | xargs du -ch 2>/dev/null | tail -1 | cut -f1 || echo "0")

          echo "Obsolete files found: $OLD_COUNT ($OLD_SIZE)"
          echo ""

          if [ "$DRY_RUN" = "true" ]; then
            echo "[DRY RUN] Files that would be deleted:"
            echo "Sample files (first 10):"
            echo "$OLD_FILES" | head -10
            if [ "$OLD_COUNT" -gt 10 ]; then
              echo "  ... and $((OLD_COUNT - 10)) more"
            fi
          else
            echo "Deleting files..."
            echo "$OLD_FILES" | xargs rm -f

            # Clean empty directories
            find distrib -type d -empty -delete 2>/dev/null || true

            echo "$OLD_COUNT files deleted ($OLD_SIZE freed)"
          fi

      - name: Report final status
        run: |
          echo ""
          echo "Final distrib cache status:"
          if [ -d "distrib" ]; then
            FILE_COUNT=$(find distrib -type f | wc -l)
            TOTAL_SIZE=$(du -sh distrib 2>/dev/null | cut -f1 || echo "0")
            TOTAL_BYTES=$(du -sb distrib 2>/dev/null | cut -f1 || echo "0")
            echo "  Files: $FILE_COUNT"
            echo "  Size: $TOTAL_SIZE"

            echo ""
            echo "Distribution by file type:"
            find distrib -type f -name "*.tar.gz" | wc -l | xargs -I{} echo "  .tar.gz: {}"
            find distrib -type f -name "*.tar.xz" | wc -l | xargs -I{} echo "  .tar.xz: {}"
            find distrib -type f -name "*.tar.bz2" | wc -l | xargs -I{} echo "  .tar.bz2: {}"
            find distrib -type f -name "*.zip" | wc -l | xargs -I{} echo "  .zip: {}"
            find distrib -type f -name "*.whl" | wc -l | xargs -I{} echo "  .whl: {}"

            echo ""
            echo "File age distribution:"
            find distrib -type f -mtime -7 | wc -l | xargs -I{} echo "  < 7 days: {}"
            find distrib -type f -mtime +7 -mtime -30 | wc -l | xargs -I{} echo "  7-30 days: {}"
            find distrib -type f -mtime +30 -mtime -90 | wc -l | xargs -I{} echo "  30-90 days: {}"
            find distrib -type f -mtime +90 -mtime -180 | wc -l | xargs -I{} echo "  90-180 days: {}"
            find distrib -type f -mtime +180 | wc -l | xargs -I{} echo "  > 180 days: {}"

            # Alert if cache size exceeds 2GB (considering other active caches in the repository)
            echo ""
            LIMIT_BYTES=2147483648
            if [ "$TOTAL_BYTES" -gt "$LIMIT_BYTES" ]; then
              echo "WARNING: Distrib cache size exceeds 2GB. Consider reducing max_age_days parameter."
            else
              echo "Cache size is within acceptable limits."
            fi
          else
            echo "  (empty)"
          fi

      - name: Compute distrib hash
        id: distrib-hash
        run: |
          # Compute a hash based on file paths and sizes (not content) for performance.
          # This is fast even with thousands of files since we don't read file contents.
          # Format: "path size" per line, sorted for reproducibility, then hashed.
          if [ -d "distrib" ] && [ -n "$(ls -A distrib 2>/dev/null)" ]; then
            HASH=$(find distrib -type f -printf '%p %s\n' | sort | sha256sum | cut -d' ' -f1)
          else
            HASH="empty"
          fi
          echo "hash=$HASH" >> $GITHUB_OUTPUT
          echo "Distrib cache hash: $HASH"

      - name: Check if cache already exists
        id: cache-check
        run: |
          # Check if a cache with this exact hash already exists to avoid duplication
          CACHE_KEY="distrib-${{ steps.distrib-hash.outputs.hash }}"
          if gh cache list --json key | jq -e --arg key "$CACHE_KEY" '.[] | select(.key == $key)' > /dev/null 2>&1; then
            echo "Cache with key $CACHE_KEY already exists, skipping save"
            echo "save_cache=false" >> $GITHUB_OUTPUT
          else
            echo "New cache content detected, will save with key: $CACHE_KEY"
            echo "save_cache=true" >> $GITHUB_OUTPUT
          fi
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

      - name: Save refreshed cache
        if: steps.cache-check.outputs.save_cache == 'true'
        uses: actions/cache/save@v5
        with:
          path: distrib
          key: distrib-${{ steps.distrib-hash.outputs.hash }}

  cleanup-stale-caches:
    runs-on: ubuntu-latest
    needs: maintain-distrib-cache
    permissions:
      actions: write
    steps:
      - name: Cleanup old GitHub cache entries
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          echo "Cleaning up old GitHub cache entries"

          # List all distrib caches with available fields
          # Note: Only targets caches with keys starting with "distrib-"
          # Other caches (e.g., toolchain-*) are not affected
          ALL_CACHES=$(gh cache list --key "distrib-" --limit 100 --json key 2>/dev/null || true)

          if [ -z "$ALL_CACHES" ] || [ "$ALL_CACHES" = "[]" ]; then
            echo "No caches found"
            exit 0
          fi

          # Count total caches
          CACHE_COUNT=$(echo "$ALL_CACHES" | jq 'length')
          echo "Found $CACHE_COUNT distrib caches"

          # Keep 10 most recent, delete the remaining 
          # Keeping more during transition period to accommodate both old and new cache formats.
          if [ "$CACHE_COUNT" -le 10 ]; then
            echo "10 or fewer caches exist, nothing to delete based on count"
          else
            CACHES_TO_DELETE=$(echo "$ALL_CACHES" | jq -r '.[10:] | .[].key' 2>/dev/null || true)

            if [ -n "$CACHES_TO_DELETE" ]; then
              echo "Deleting old caches (keeping 10 most recent):"
              for key in $CACHES_TO_DELETE; do
                echo "  Deleting: $key"
                gh cache delete "$key" --confirm 2>/dev/null || true
              done
            fi
          fi

          echo ""
          echo "Cleanup completed"