agent-queue-drain.yml

name: Trinity Agent Queue Drain
on:
  schedule:
    - cron: '*/5 * * * *'  # Every 5 minutes
  workflow_dispatch: {}

concurrency:
  group: agent-queue-drain
  cancel-in-progress: false

jobs:
  drain-queue:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      issues: write
    steps:
      - name: Check for queued issues and free slots
        env:
          RAILWAY_API_TOKEN: ${{ secrets.RAILWAY_API_TOKEN }}
          RAILWAY_PROJECT_ID: ${{ secrets.RAILWAY_PROJECT_ID }}
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -e

          # 1. Check if any slots are free
          DEPLOYMENTS=$(curl -s -X POST "https://backboard.railway.com/graphql/v2" \
            -H "Authorization: Bearer ${RAILWAY_API_TOKEN}" \
            -H "Content-Type: application/json" \
            -d "{
              \"query\": \"query(\$id: String!) { project(id: \$id) { services { edges { node { id name deployments(first: 1) { edges { node { status } } } } } } } }\",
              \"variables\": { \"id\": \"${RAILWAY_PROJECT_ID}\" }
            }")

          ACTIVE_COUNT=$(echo "$DEPLOYMENTS" | jq '[.data.project.services.edges[].node | select(.name | startswith("agent-")) | .deployments.edges[0].node.status // ""] | map(select(. == "BUILDING" or . == "DEPLOYING")) | length')

          if [ "$ACTIVE_COUNT" -gt 0 ]; then
            echo "⏳ $ACTIVE_COUNT active agent(s) — no free slots, skipping drain"
            exit 0
          fi

          # 2. Find oldest queued issue
          QUEUED=$(gh issue list \
            --repo ${{ github.repository }} \
            --label "agent:queued" \
            --state open \
            --json number \
            --jq '.[0].number // empty' 2>/dev/null || true)

          if [ -z "$QUEUED" ]; then
            echo "✅ No queued issues"
            exit 0
          fi

          echo "🚀 Draining queue: spawning agent for issue #${QUEUED}"

          # 3. Remove queued label, add spawn label to trigger agent-spawn workflow
          gh issue edit "${QUEUED}" \
            --repo ${{ github.repository }} \
            --remove-label "agent:queued" \
            --add-label "agent:spawn"

          gh issue comment "${QUEUED}" \
            --repo ${{ github.repository }} \
            --body "🔄 **Queue drain**: Slot freed, re-triggering agent spawn."