name: validate

on:
  push:
    branches: [main]
  pull_request:

jobs:
  validate:
    runs-on: ubuntu-latest
    env:
      # Dummy values so `compose config` doesn't fail on the `:?required` guards.
      ALLOY_HOSTNAME: ci
      PROM_URL:       https://example.com
      PROM_USER:      "1"
      LOKI_URL:       https://example.com
      LOKI_USER:      "1"
      GRAFANA_TOKEN:  x
    steps:
      - uses: actions/checkout@v4

      - name: Validate compose YAML + env interpolation
        run: docker compose config -q

      - name: Extract embedded Alloy config
        uses: mikefarah/yq@v4
        with:
          cmd: yq '.configs.alloy_config.content' docker-compose.yml > config.alloy

      - name: Validate Alloy config syntax
        run: |
          docker run --rm -v "$PWD/config.alloy:/config.alloy:ro" \
            grafana/alloy:v1.10.0 fmt /config.alloy > /dev/null