ci.yml

name: CI

on:
  pull_request:
  push:
    branches: [main]

# Cancel superseded PR runs; keep main builds.
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: ${{ github.event_name == 'pull_request' }}

permissions:
  contents: read

jobs:
  changes:
    name: Detect code changes
    runs-on: ubuntu-latest
    permissions:
      pull-requests: read
    outputs:
      full_ci: ${{ github.event_name != 'pull_request' || (!startsWith(github.event.pull_request.title, 'docs') && steps.filter.outputs.full_ci == 'true') }}
    steps:
      - name: Detect non-documentation changes
        id: filter
        if: github.event_name == 'pull_request' && !startsWith(github.event.pull_request.title, 'docs')
        uses: dorny/paths-filter@v4
        with:
          predicate-quantifier: every
          filters: |
            full_ci:
              - "**"
              - "!docs/**"
              - "!*.md"
              - "!**/README.md"
              - "!benchmark/*.md"
              - "!.github/ISSUE_TEMPLATE/**"
              - "!.github/PULL_REQUEST_TEMPLATE.md"
              - "!.agents/skills/**/*.md"

  # ruff is a hard gate — the codebase passes today, keep it that way.
  lint:
    name: Lint (ruff)
    needs: changes
    if: needs.changes.outputs.full_ci == 'true'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: astral-sh/setup-uv@v6
        with:
          python-version: "3.12"
          enable-cache: true
          cache-dependency-glob: "uv.lock"
      - run: uv sync --locked
      - name: ruff check
        run: uv run ruff check .

  # SPDX headers are a hard gate — every Python file must carry the exact
  # NVIDIA OSRB-required two-line form (SPDX-FileCopyrightText with the
  # canonical wording, immediately followed by SPDX-License-Identifier:
  # Apache-2.0). A leading shebang is permitted; the header must appear
  # within the first four lines.
  spdx-headers:
    name: SPDX License Headers
    needs: changes
    if: needs.changes.outputs.full_ci == 'true'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Check SPDX headers
        run: |
          set -u
          copyright_re='^# SPDX-FileCopyrightText: Copyright \(c\) [0-9]{4}(-[0-9]{4})? NVIDIA CORPORATION & AFFILIATES\. All rights reserved\.$'
          license_re='^# SPDX-License-Identifier: Apache-2\.0$'
          missing=0
          while IFS= read -r file; do
            head4=$(head -4 "$file")
            if ! printf '%s\n' "$head4" | grep -Eq "$copyright_re"; then
              echo "FAIL ($file): missing or malformed SPDX-FileCopyrightText line"
              missing=$((missing+1))
              continue
            fi
            if ! printf '%s\n' "$head4" | grep -Eq "$license_re"; then
              echo "FAIL ($file): missing SPDX-License-Identifier: Apache-2.0"
              missing=$((missing+1))
              continue
            fi
          done < <(find . -name '*.py' -type f \
            ! -path './.venv/*' \
            ! -path './.git/*' \
            ! -path './__pycache__/*' \
            ! -path '*/.pytest_cache/*' \
            ! -path '*/.eggs/*' \
            ! -path '*.egg-info/*')
          if [ "$missing" -gt 0 ]; then
            echo "FAIL: $missing Python files missing or malformed SPDX header"
            exit 1
          fi
          echo "OK: All Python files carry the required SPDX header"

  rust:
    name: Rust
    needs: changes
    if: needs.changes.outputs.full_ci == 'true'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Install Rust components
        run: rustup component add rustfmt clippy
      - name: cargo fmt
        run: cargo fmt --all --check
      - name: cargo clippy
        run: cargo clippy --workspace --all-targets -- -D warnings
      - name: cargo test
        run: cargo test --workspace

  typecheck:
    name: Typecheck (mypy)
    needs: changes
    if: needs.changes.outputs.full_ci == 'true'
    runs-on: ubuntu-latest
    continue-on-error: true
    steps:
      - uses: actions/checkout@v4
      - uses: astral-sh/setup-uv@v6
        with:
          python-version: "3.12"
          enable-cache: true
          cache-dependency-glob: "uv.lock"
      - run: uv sync --locked
      - name: mypy
        run: uv run mypy switchyard

  # Unit tests on supported Python versions. Integration/e2e tests are
  # intentionally deselected here because they may need Docker, live provider
  # credentials, or network egress.
  test:
    name: Tests (Python ${{ matrix.python-version }})
    needs: changes
    if: needs.changes.outputs.full_ci == 'true'
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.12", "3.13", "3.14"]
    steps:
      - uses: actions/checkout@v4
      - uses: astral-sh/setup-uv@v6
        with:
          python-version: ${{ matrix.python-version }}
          enable-cache: true
          cache-dependency-glob: "uv.lock"
      - run: uv sync --locked
      - name: pytest
        run: uv run pytest tests/ -v -m "not integration"

  # Regression guard: the default install of nemo-switchyard (without extras)
  # must NOT drag in torch / transformers / routellm / litellm /
  # openai-agents / docx. Catches accidental top-level imports of
  # heavy packages before they hit users as ~1 GB of install bloat.
  #
  # This is the actual hard gate on the workflow.
  slim-install-smoke:
    name: Slim install smoke test
    needs: changes
    if: needs.changes.outputs.full_ci == 'true'
    runs-on: ubuntu-latest
    env:
      SWITCHYARD_DEFAULT_PACKAGE: "nemo-switchyard @ file://${{ github.workspace }}"
      SWITCHYARD_EXTRAS_PACKAGE: "nemo-switchyard[cli,server] @ file://${{ github.workspace }}"
    steps:
      - uses: actions/checkout@v4
      - uses: astral-sh/setup-uv@v6
        with:
          python-version: "3.12"
          enable-cache: true
          cache-dependency-glob: "uv.lock"
      - name: Verify slim install (no extras) succeeds
        working-directory: /tmp
        run: |
          uv run --isolated --no-project --python 3.12 \
            --with "${SWITCHYARD_DEFAULT_PACKAGE}" \
            python -c "import switchyard; print('import OK, version:', switchyard.__version__)"
          uv run --isolated --no-project --python 3.14 \
            --with "${SWITCHYARD_DEFAULT_PACKAGE}" \
            python -c "import switchyard; print('import OK, version:', switchyard.__version__)"
          uv run --isolated --no-project --python 3.12 \
            --with "${SWITCHYARD_DEFAULT_PACKAGE}" \
            python -c "from switchyard import RandomRoutingPresets; print('preset import OK:', sorted(RandomRoutingPresets.PRESETS))"
      - name: Assert heavy packages absent from slim install
        working-directory: /tmp
        run: |
          uv run --isolated --no-project --python 3.12 \
            --with "${SWITCHYARD_DEFAULT_PACKAGE}" \
            python - <<'PY'
          import importlib.util
          import sys

          forbidden = [
              "torch",
              "transformers",
              "huggingface_hub",
              "routellm",
              "litellm",
              "datasets",
              "tokenizers",
              "safetensors",
              "pyarrow",
              "agents",
              "mcp",
              "docx",
          ]
          extras = [m for m in forbidden if importlib.util.find_spec(m) is not None]
          if extras:
              sys.exit(f"FAIL: heavy packages pulled into slim install: {extras}")
          print(f"OK: all {len(forbidden)} heavy packages absent from slim install.")
          PY
      - name: Verify CLI and server imports work with extras
        working-directory: /tmp
        run: |
          uv run --isolated --no-project --python 3.12 \
            --with "${SWITCHYARD_EXTRAS_PACKAGE}" \
            switchyard launch claude --help > /dev/null
          uv run --isolated --no-project --python 3.12 \
            --with "${SWITCHYARD_EXTRAS_PACKAGE}" \
            switchyard launch claude --help 2>&1 | grep -q -- '--model' || { echo 'FAIL: --model flag missing from help'; exit 1; }
          uv run --isolated --no-project --python 3.12 \
            --with "${SWITCHYARD_EXTRAS_PACKAGE}" \
            switchyard launch claude --help 2>&1 | grep -q -- '--config' || { echo 'FAIL: --config flag missing from help'; exit 1; }
          uv run --isolated --no-project --python 3.12 \
            --with "${SWITCHYARD_EXTRAS_PACKAGE}" \
            switchyard serve --help > /dev/null

  # Single required check for branch protection. Gates on every job above so
  # the ruleset never needs editing when jobs are added or renamed.
  ci-success:
    name: CI Success
    if: always()
    needs: [changes, lint, spdx-headers, rust, typecheck, test, slim-install-smoke]
    runs-on: ubuntu-latest
    steps:
      - name: Verify all jobs succeeded
        if: ${{ contains(needs.*.result, 'failure') || contains(needs.*.result, 'cancelled') }}
        run: exit 1