codeql.yml

name: CodeQL

# CodeQL's code scanning of the workflows, the TypeScript and the Rust, with the paths in
# .github/codeql/codeql-config.yml left out (the Rust tests). Default setup ran the same languages
# and suite but can't take a config file. Each language uploads under the category default setup
# used, so its alerts carry over.
#
# ci.yml calls it for every pull request into main, merge queue group and push to main but a
# draft's, with every language whatever changed. The "Protect Main" ruleset's code scanning rule
# holds a pull request or a merge queue group until its commit has a result in every category
# main has (netresearch/.github#170 had every queued pull request stuck on "Code scanning is still
# expecting 1 result from CodeQL", and so did #347 when only the languages that changed ran).
# CodeQL's own result is that check. No weekly run: main gets pushes most days, and each analyses
# with the queries of the action's pinned bundle.
#
# A language whose code, CodeQL config and this workflow are as they were at the commit ci.yml
# diffed against has that commit's results, so its job uploads that commit's analysis from main
# again, for this commit, in place of analysing it: about a minute where Rust takes 15 to 19.
# With no such analysis on main yet (its push run hasn't got there), it analyses.
on:
  workflow_call:
    inputs:
      unchanged:
        description: The languages whose code didn't change, as a JSON list.
        type: string
        required: true
      base:
        description: The commit ci.yml diffed a push or a merge queue group against; empty for a pull request, whose merge commit's first parent is the one.
        type: string
        required: true

permissions: {}

# Actions are pinned to commits (Dependabot keeps them current, see .github/dependabot.yml).
jobs:
  analyze:
    name: Analyze (${{ matrix.language }})
    runs-on: ubuntu-latest
    # Default setup's Rust analysis took 15 to 19 minutes with the tests in.
    timeout-minutes: 40
    permissions:
      # Uploading the results to code scanning.
      security-events: write
      contents: read
    strategy:
      fail-fast: false
      matrix:
        language: [actions, javascript-typescript, rust]
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false
          # A pull request's merge commit and its first parent.
          fetch-depth: 2
      # main's analysis of the base commit in this language, when its code is unchanged and main
      # has one. The list is filtered here (see .github/actions/last-passed).
      - id: reuse
        if: contains(fromJSON(inputs.unchanged), matrix.language)
        env:
          GH_TOKEN: ${{ github.token }}
          GH_REPO: ${{ github.repository }}
          BASE: ${{ inputs.base }}
          CATEGORY: /language:${{ matrix.language }}
        run: |
          base=${BASE:-$(git rev-parse HEAD^1)}
          id=$(gh api "repos/$GH_REPO/code-scanning/analyses?ref=refs/heads/main&tool_name=CodeQL&per_page=100" |
            jq -r --arg category "$CATEGORY" --arg sha "$base" \
              '[.[] | select(.category == $category and .commit_sha == $sha and .error == "")][0].id // empty')
          if [ -z "$id" ]; then
            echo "main has no $CATEGORY analysis of $base yet, so this one analyses"
            exit 0
          fi
          gh api -H "Accept: application/sarif+json" "repos/$GH_REPO/code-scanning/analyses/$id" > "$RUNNER_TEMP/main.sarif"
          echo "Reusing analysis $id of $base"
          echo "sarif=$RUNNER_TEMP/main.sarif" >> "$GITHUB_OUTPUT"
      - if: steps.reuse.outputs.sarif != ''
        uses: github/codeql-action/upload-sarif@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
        with:
          sarif_file: ${{ steps.reuse.outputs.sarif }}
          category: /language:${{ matrix.language }}
      # Nothing is built: Rust and TypeScript are read from the source, which is also what lets
      # paths-ignore leave files out.
      - if: steps.reuse.outputs.sarif == ''
        uses: github/codeql-action/init@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
        with:
          languages: ${{ matrix.language }}
          build-mode: none
          config-file: ./.github/codeql/codeql-config.yml
      - if: steps.reuse.outputs.sarif == ''
        uses: github/codeql-action/analyze@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
        with:
          category: /language:${{ matrix.language }}