loadtest-stress.yml

name: Performance Stress Test (Nightly)

on:
  push:
    branches: [main]
  pull_request:
    paths:
      - '.github/workflows/loadtest-stress.yml'
  schedule:
    # Runs at 02:00 UTC every night
    - cron: '0 2 * * *'
  # Allow manual triggering from the Actions tab
  workflow_dispatch:

permissions:
  contents: read

jobs:
  loadtest-stress:
    name: k6 Full Stress Test
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v7

      - name: Set up Go
        uses: actions/setup-go@v6
        with:
          go-version-file: 'go.mod'
          cache: true

      - name: Download dependencies
        run: go mod download

      - name: Build Maglev
        run: make build

      - name: Create CI config
        run: |
          cat > config.ci.json << 'EOF'
          {
            "port": 4000,
            "env": "development",
            "api-keys": ["test"],
            "rate-limit": 1000,
            "log-level": "warn",
            "log-format": "json",
            "gtfs-static-feed": {
              "url": "testdata/raba.zip",
              "enable-gtfs-tidy": false
            },
            "gtfs-rt-feeds": [],
            "data-path": "./ci-gtfs.db"
          }
          EOF

      - name: Start Maglev server (with pprof enabled)
        run: |
          MAGLEV_ENABLE_PPROF=1 ./bin/maglev -f config.ci.json > maglev.log 2>&1 &
          echo "MAGLEV_PID=$!" >> $GITHUB_ENV

      - name: Wait for server to be ready
        run: |
          echo "Waiting for Maglev to be ready..."
          for i in $(seq 1 60); do
            if curl -sf http://localhost:4000/healthz > /dev/null 2>&1; then
              echo "Server is ready after ${i} attempts."
              exit 0
            fi
            echo "  Attempt $i/60 — not ready yet, waiting 5s..."
            tail -1 maglev.log 2>/dev/null || true
            sleep 5
          done
          echo "ERROR: Server did not become ready in time. Dumping logs:"
          cat maglev.log
          exit 1

      - name: Install k6
        run: |
          sudo gpg -k
          sudo gpg --no-default-keyring \
            --keyring /usr/share/keyrings/k6-archive-keyring.gpg \
            --keyserver hkp://keyserver.ubuntu.com:80 \
            --recv-keys C5AD17C747E3415A3642D57D77C6C491D6AC1D69
          echo "deb [signed-by=/usr/share/keyrings/k6-archive-keyring.gpg] https://dl.k6.io/deb stable main" \
            | sudo tee /etc/apt/sources.list.d/k6.list
          sudo apt-get update -qq
          sudo apt-get install -y k6

      - name: Capture pprof baseline (before load)
        run: |
          mkdir -p loadtest/profiles
          curl -sf "http://localhost:6060/debug/pprof/heap" -o loadtest/profiles/heap-before.pprof || true
          curl -sf "http://localhost:6060/debug/pprof/goroutine" -o loadtest/profiles/goroutine-before.pprof || true

      - name: Run k6 full stress test
        run: |
          # Wait 60s for ramp-up, then capture 30s CPU profile during peak load
          (sleep 60 && curl -sf "http://localhost:6060/debug/pprof/profile?seconds=30" -o loadtest/profiles/cpu.pprof) &
          PPROF_PID=$!

          k6 run \
            -e USE_FALLBACKS=true \
            loadtest/k6/scenarios.js

          # Wait for the background profile to finish and gracefully catch any errors
          wait $PPROF_PID || echo "Warning: Background CPU profile capture failed."
        continue-on-error: true
        id: k6_stress

      - name: Capture pprof profiles (after load)
        if: always()
        run: |
          curl -sf "http://localhost:6060/debug/pprof/heap" -o loadtest/profiles/heap-after.pprof || true
          curl -sf "http://localhost:6060/debug/pprof/goroutine" -o loadtest/profiles/goroutine-after.pprof || true
          curl -sf "http://localhost:6060/debug/pprof/mutex" -o loadtest/profiles/mutex-after.pprof || true
          # Note: CPU profile is captured concurrently during the test above

      - name: Stop Maglev server
        if: always()
        run: |
          kill $MAGLEV_PID 2>/dev/null || true

      - name: Upload stress test results and profiles
        if: always()
        uses: actions/upload-artifact@v7
        with:
          name: k6-stress-results-${{ github.sha }}
          path: |
            loadtest/k6/stress-summary.json
            loadtest/profiles/
            maglev.log

      - name: Fail job if k6 thresholds were exceeded
        if: steps.k6_stress.outcome == 'failure'
        run: |
          echo "k6 stress test thresholds were exceeded. Download the k6-stress-results artifact for pprof profiles."
          exit 1