cleanup-workflow-runs.yml

name: Cleanup Old Workflow Runs

on:
  schedule:
    - cron: '0 * * * *'  # Run every Sunday at 3 AM UTC
  workflow_dispatch:
    inputs:
      retain_days:
        description: 'Delete runs older than this many days'
        required: false
        type: number
        default: '30'
      keep_minimum_runs:
        description: 'Always keep at least this many recent runs per workflow'
        required: false
        type: number
        default: '5'
      dry_run:
        description: 'Dry run — log what would be deleted without actually deleting'
        required: false
        type: boolean
        default: false
      max_deletions:
        description: 'Maximum number of runs to delete per execution (prevents rate limiting)'
        required: false
        type: number
        default: 300

permissions:
  actions: write  # Required to delete workflow runs

jobs:
  cleanup:
    runs-on: ubuntu-latest

    steps:
    - name: 🧹 Delete old workflow runs
      env:
        GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        REPO: ${{ github.repository }}
        RETAIN_DAYS: ${{ inputs.retain_days || '30' }}
        KEEP_MINIMUM_RUNS: ${{ inputs.keep_minimum_runs || '5' }}
        DRY_RUN: ${{ inputs.dry_run || 'false' }}
        MAX_DELETIONS: ${{ inputs.max_deletions || '100' }}
      run: |
        set -euo pipefail
        # Strip any decimal suffix (e.g., 30.0 → 30)
        RETAIN_DAYS=${RETAIN_DAYS%.*}
        KEEP_MINIMUM_RUNS=${KEEP_MINIMUM_RUNS%.*}
        MAX_DELETIONS=${MAX_DELETIONS%.*}
        TOTAL_DELETED=0
        TOTAL_RETAINED=0
        SUMMARY_ROWS=""

        # Cutoff timestamp in seconds since epoch
        CUTOFF=$(date -d "-${RETAIN_DAYS} days" +%s)

        echo "ℹ️  retain_days=${RETAIN_DAYS}  keep_minimum_runs=${KEEP_MINIMUM_RUNS}  dry_run=${DRY_RUN}  max_deletions=${MAX_DELETIONS}"
        echo "ℹ️  Cutoff date: $(date -d "-${RETAIN_DAYS} days" --utc +%Y-%m-%dT%H:%M:%SZ)"

        RATE_REMAINING=$(gh api rate_limit --jq '.rate.remaining' 2>/dev/null || echo "unknown")
        echo "ℹ️  API rate limit remaining: ${RATE_REMAINING}"

        # Fetch all workflows (paginated)
        WORKFLOWS=$(gh api "repos/${REPO}/actions/workflows?per_page=100" \
          --paginate \
          --jq '.workflows[] | "\(.id)\t\(.name)"')

        while IFS=$'\t' read -r WF_ID WF_NAME; do
          echo ""
          echo "▶ Processing workflow: ${WF_NAME} (id=${WF_ID})"

          # Collect completed run IDs and their created_at timestamps,
          # newest first (API default ordering is newest-first by created_at)
          RUNS=$(gh api \
            "repos/${REPO}/actions/workflows/${WF_ID}/runs?status=completed&per_page=100" \
            --jq '.workflow_runs[] | "\(.id)\t\(.created_at)"' || echo "")

          # Sanitize workflow name for markdown table (escape pipe characters)
          WF_NAME_SAFE="${WF_NAME//|/\\|}"

          if [ -z "${RUNS}" ]; then
            echo "  ℹ️  No completed runs found."
            SUMMARY_ROWS="${SUMMARY_ROWS}| ${WF_NAME_SAFE} | 0 | 0 |\n"
            continue
          fi

          WF_DELETED=0
          WF_RETAINED=0
          RUN_INDEX=0

          while IFS=$'\t' read -r RUN_ID RUN_CREATED; do
            RUN_INDEX=$((RUN_INDEX + 1))

            # Always keep the most recent KEEP_MINIMUM_RUNS runs
            if [ "${RUN_INDEX}" -le "${KEEP_MINIMUM_RUNS}" ]; then
              echo "  ✅ Keeping run ${RUN_ID} (${RUN_CREATED}) — within minimum keep count"
              WF_RETAINED=$((WF_RETAINED + 1))
              continue
            fi

            # Check age
            RUN_TS=$(date -d "${RUN_CREATED}" +%s)
            if [ "${RUN_TS}" -ge "${CUTOFF}" ]; then
              echo "  ✅ Keeping run ${RUN_ID} (${RUN_CREATED}) — within retention period"
              WF_RETAINED=$((WF_RETAINED + 1))
              continue
            fi

            # Delete (or dry-run log)
            if [ "${DRY_RUN}" = "true" ]; then
              echo "  🔍 [DRY RUN] Would delete run ${RUN_ID} (${RUN_CREATED})"
            else
              if [ "$(( TOTAL_DELETED + WF_DELETED ))" -ge "${MAX_DELETIONS}" ]; then
                echo "  ⚠️ Reached maximum deletions (${MAX_DELETIONS}), stopping. Will continue in next run."
                break
              fi
              echo "  🗑️  Deleting run ${RUN_ID} (${RUN_CREATED})"
              if ! gh api --method DELETE "repos/${REPO}/actions/runs/${RUN_ID}" 2>/dev/null; then
                echo "    ⚠️ Delete failed (possibly rate-limited), stopping deletions for this workflow"
                break
              fi
              sleep 1
            fi
            WF_DELETED=$((WF_DELETED + 1))
          done <<< "${RUNS}"

          echo "  Summary: deleted=${WF_DELETED}  retained=${WF_RETAINED}"
          TOTAL_DELETED=$((TOTAL_DELETED + WF_DELETED))
          TOTAL_RETAINED=$((TOTAL_RETAINED + WF_RETAINED))
          SUMMARY_ROWS="${SUMMARY_ROWS}| ${WF_NAME_SAFE} | ${WF_RETAINED} | ${WF_DELETED} |\n"

          if [ "${TOTAL_DELETED}" -ge "${MAX_DELETIONS}" ]; then
            echo ""
            echo "⚠️ Reached maximum deletions cap (${MAX_DELETIONS}). Remaining cleanup will happen in the next scheduled run."
            break
          fi
        done <<< "${WORKFLOWS}"

        echo ""
        echo "✅ Done. Total deleted: ${TOTAL_DELETED}  Total retained: ${TOTAL_RETAINED}"

        # Write step summary
        {
          if [ "${DRY_RUN}" = "true" ]; then
            echo "### 🔍 Workflow Runs Cleanup — Dry Run"
          else
            echo "### 🧹 Workflow Runs Cleanup"
          fi
          echo ""
          echo "| Setting | Value |"
          echo "| --- | --- |"
          echo "| Retain days | ${RETAIN_DAYS} |"
          echo "| Keep minimum runs | ${KEEP_MINIMUM_RUNS} |"
          echo "| Max deletions per run | ${MAX_DELETIONS} |"
          echo "| Dry run | ${DRY_RUN} |"
          echo ""
          echo "| Workflow | Retained | Deleted |"
          echo "| --- | --- | --- |"
          printf "%b" "${SUMMARY_ROWS}"
          echo ""
          echo "| **Total** | **${TOTAL_RETAINED}** | **${TOTAL_DELETED}** |"
          if [ "${TOTAL_DELETED}" -ge "${MAX_DELETIONS}" ]; then
            echo ""
            echo "> ⚠️ **Deletion cap reached** (${MAX_DELETIONS}). Run the workflow again or wait for the next scheduled run to continue cleanup."
          fi
        } >> "${GITHUB_STEP_SUMMARY}"