name: Downstream smoke

# Drive this checkout's FastMCP through the frameworks that depend on it, the
# way uv's ecosystem tests drive downstream projects: build once, install that
# build where the consumer runs, and run the consumer's own usage against it.
#
# Pushes and PRs use the pinned versions below, so a failure points at the
# change under test. The nightly run resolves each consumer's latest release
# to catch breakage that ships downstream.

env:
  PY_COLORS: 1
  PYDANTIC_AI_VERSION: "2.47.0"
  LANGCHAIN_MCP_ADAPTERS_VERSION: "0.3.2"
  LANGCHAIN_VERSION: "1.4.2"

on:
  push:
    branches: ["main"]
    paths:
      - "fastmcp_slim/**"
      - "fastmcp_tasks/**"
      - "tests/downstream/**"
      - "pyproject.toml"
      - "uv.lock"
      - ".github/workflows/run-downstream-smoke.yml"

  pull_request:
    paths:
      - "fastmcp_slim/**"
      - "fastmcp_tasks/**"
      - "tests/downstream/**"
      - "pyproject.toml"
      - "uv.lock"
      - ".github/workflows/run-downstream-smoke.yml"

  schedule:
    - cron: "30 2 * * *"

  workflow_dispatch:
    inputs:
      latest:
        description: "Test each consumer's latest release instead of the pins"
        type: boolean
        default: false

concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_id }}
  cancel-in-progress: ${{ github.event_name == 'pull_request' }}

permissions:
  contents: read

jobs:
  plan:
    name: Plan
    runs-on: ubuntu-latest
    timeout-minutes: 5
    outputs:
      fastmcp: ${{ steps.build.outputs.version }}
      pydantic-ai: ${{ steps.versions.outputs.pydantic-ai }}
      langchain-mcp-adapters: ${{ steps.versions.outputs.langchain-mcp-adapters }}
      langchain: ${{ steps.versions.outputs.langchain }}
    steps:
      - uses: actions/checkout@v7
        with:
          fetch-depth: 0

      - name: Install uv
        uses: astral-sh/setup-uv@v10.3.0

      - name: Build wheels
        id: build
        run: |
          for package in . fastmcp_slim fastmcp_tasks; do
            uv build --quiet --wheel --out-dir dist "$package"
          done
          version=$(basename dist/fastmcp_slim-*.whl | cut -d- -f2)
          echo "version=$version" >> "$GITHUB_OUTPUT"
          ls dist

      - uses: actions/upload-artifact@v7
        with:
          name: fastmcp-wheels
          path: dist/*.whl

      - name: Choose consumer versions
        id: versions
        env:
          LATEST: ${{ github.event_name == 'schedule' || inputs.latest == true }}
        run: |
          set -euo pipefail
          pick() {
            local version="$2"
            if [ "$LATEST" = true ]; then
              version=$(curl -fsS --retry 5 --retry-all-errors "https://pypi.org/pypi/$1/json" | jq -r .info.version)
            fi
            if [ -z "$version" ] || [ "$version" = null ]; then
              echo "::error::could not resolve a version for $1" >&2
              exit 1
            fi
            echo "$version"
          }
          pydantic_ai=$(pick pydantic-ai-slim "$PYDANTIC_AI_VERSION")
          adapters=$(pick langchain-mcp-adapters "$LANGCHAIN_MCP_ADAPTERS_VERSION")
          langchain=$(pick langchain "$LANGCHAIN_VERSION")
          {
            echo "pydantic-ai=$pydantic_ai"
            echo "langchain-mcp-adapters=$adapters"
            echo "langchain=$langchain"
          } | tee -a "$GITHUB_OUTPUT" > versions.txt
          {
            echo "### Downstream smoke plan"
            echo
            echo "FastMCP \`$(basename dist/fastmcp_slim-*.whl | cut -d- -f2)\` against $([ "$LATEST" = true ] && echo "each consumer's latest release" || echo "pinned consumer versions")"
            echo
            echo "| consumer | version |"
            echo "|---|---|"
            sed 's/^\(.*\)=\(.*\)$/| \1 | `\2` |/' versions.txt
          } >> "$GITHUB_STEP_SUMMARY"

  pydantic-ai-suite:
    name: pydantic-ai test suite
    needs: plan
    runs-on: ubuntu-latest
    timeout-minutes: 15
    steps:
      - uses: actions/checkout@v7
        with:
          path: fastmcp

      - uses: actions/checkout@v7
        with:
          repository: pydantic/pydantic-ai
          ref: v${{ needs.plan.outputs.pydantic-ai }}
          path: pydantic-ai
          persist-credentials: false

      - uses: actions/download-artifact@v8
        with:
          name: fastmcp-wheels
          path: dist

      - name: Install uv
        uses: astral-sh/setup-uv@v10.3.0
        with:
          python-version: "3.13"
          enable-cache: true
          cache-dependency-glob: pydantic-ai/uv.lock

      # Mirrors pydantic-ai's own "test FastMCP 4 compatibility" job: their locked
      # environment, with FastMCP overlaid from the wheels under test.
      - name: Resolve environment
        working-directory: pydantic-ai
        run: |
          echo "UV_RUN=uv run --all-extras --no-extra mcp-tasks --all-packages \
            --exclude-newer-package pydocket=2026-10-03T00:00:00Z \
            --with fastmcp@file://$(ls $GITHUB_WORKSPACE/dist/fastmcp-4*.whl) \
            --with fastmcp-slim@file://$(ls $GITHUB_WORKSPACE/dist/fastmcp_slim-*.whl) \
            --with fastmcp-tasks@file://$(ls $GITHUB_WORKSPACE/dist/fastmcp_tasks-*.whl)" >> "$GITHUB_ENV"

      - name: Check the build under test is installed
        working-directory: pydantic-ai
        run: >-
          $UV_RUN --quiet python -c "import fastmcp, mcp, importlib.metadata as m;
          assert fastmcp.__version__ == '${{ needs.plan.outputs.fastmcp }}', fastmcp.__version__;
          print('fastmcp', fastmcp.__version__, '· mcp', m.version('mcp'))"

      - name: Run pydantic-ai's MCP tests
        working-directory: pydantic-ai
        run: >-
          $UV_RUN --quiet pytest -p no:cacheprovider -q
          --junitxml=$GITHUB_WORKSPACE/junit.xml
          tests/test_mcp.py tests/models/test_mcp_sampling.py tests/test_conftest.py

      - name: Summarize
        if: always() && hashFiles('junit.xml') != ''
        run: python3 fastmcp/tests/downstream/_harness.py junit.xml "pydantic-ai ${{ needs.plan.outputs.pydantic-ai }} MCP test suite"

  langchain-suite:
    name: langchain test suite
    needs: plan
    runs-on: ubuntu-latest
    timeout-minutes: 15
    steps:
      - uses: actions/checkout@v7
        with:
          path: fastmcp

      - uses: actions/checkout@v7
        with:
          repository: langchain-ai/langchain
          ref: langchain==${{ needs.plan.outputs.langchain }}
          path: langchain
          persist-credentials: false

      - uses: actions/download-artifact@v8
        with:
          name: fastmcp-wheels
          path: dist

      - name: Install uv
        uses: astral-sh/setup-uv@v10.3.0
        with:
          python-version: "3.13"
          enable-cache: true
          cache-dependency-glob: langchain/libs/langchain_v1/uv.lock

      # langchain.mcp builds on fastmcp.Client and ClientGroup; run its own MCP
      # tests in its locked environment with FastMCP overlaid from the wheels.
      - name: Resolve environment
        working-directory: langchain/libs/langchain_v1
        run: |
          echo "UV_RUN=uv run --group test \
            --with fastmcp@file://$(ls $GITHUB_WORKSPACE/dist/fastmcp-4*.whl) \
            --with fastmcp-slim@file://$(ls $GITHUB_WORKSPACE/dist/fastmcp_slim-*.whl)" >> "$GITHUB_ENV"

      - name: Check the build under test is installed
        working-directory: langchain/libs/langchain_v1
        run: >-
          $UV_RUN --quiet python -c "import fastmcp;
          assert fastmcp.__version__ == '${{ needs.plan.outputs.fastmcp }}', fastmcp.__version__;
          print('fastmcp', fastmcp.__version__)"

      # The deselected test asserts on the caller's Client while MCPAdapter
      # connects a clone, so it fails against every fastmcp 4.0.x release.
      - name: Run langchain's MCP tests
        working-directory: langchain/libs/langchain_v1
        run: >-
          $UV_RUN --quiet pytest -p no:cacheprovider -q
          --junitxml=$GITHUB_WORKSPACE/junit.xml
          tests/unit_tests/mcp tests/integration_tests/mcp
          --deselect tests/integration_tests/mcp/test_protocol_eras.py::test_separate_adapters_keep_their_own_protocol_era

      - name: Summarize
        if: always() && hashFiles('junit.xml') != ''
        run: python3 fastmcp/tests/downstream/_harness.py junit.xml "langchain ${{ needs.plan.outputs.langchain }} MCP test suite"

  smoke:
    name: ${{ matrix.consumer }} smoke
    needs: plan
    runs-on: ubuntu-latest
    timeout-minutes: 10
    strategy:
      fail-fast: false
      matrix:
        include:
          # Client-only, as `pydantic-ai-slim[mcp]` installs it, with the build under test.
          - consumer: pydantic-ai
            script: smoke_pydantic_ai.py
            with: >-
              --with "pydantic-ai-slim[mcp]==${{ needs.plan.outputs.pydantic-ai }}"
              --with "fastmcp-slim[client] @ file://$GITHUB_WORKSPACE/$(ls dist/fastmcp_slim-*.whl)"
          # langchain.mcp wraps fastmcp.Client and ClientGroup, with the build under test.
          - consumer: langchain.mcp
            script: smoke_langchain_mcp.py
            with: >-
              --with "langchain[mcp]==${{ needs.plan.outputs.langchain }}"
              --with "fastmcp @ file://$GITHUB_WORKSPACE/$(ls dist/fastmcp-4*.whl)"
              --with "fastmcp-slim @ file://$GITHUB_WORKSPACE/$(ls dist/fastmcp_slim-*.whl)"
          # The adapters pin mcp<2, so they reach FastMCP over the wire.
          - consumer: langchain-mcp-adapters
            script: smoke_langchain_mcp_adapters.py
            with: >-
              --with "langchain-mcp-adapters==${{ needs.plan.outputs.langchain-mcp-adapters }}"
              --with "langchain==${{ needs.plan.outputs.langchain }}"
    env:
      FASTMCP_EXPECTED_VERSION: ${{ needs.plan.outputs.fastmcp }}
    steps:
      - uses: actions/checkout@v7

      # The servers every smoke connects to run from this environment.
      - name: Setup uv
        uses: ./.github/actions/setup-uv
        with:
          python-version: "3.12"

      - uses: actions/download-artifact@v8
        with:
          name: fastmcp-wheels
          path: dist

      # Resolved outside the project and without its config, as a user's install is.
      - name: Resolve ${{ matrix.consumer }} environment
        run: uv run --isolated --no-project --no-config ${{ matrix.with }} python -c pass

      - name: Run ${{ matrix.consumer }} smoke
        run: uv run --quiet --isolated --no-project --no-config ${{ matrix.with }} python tests/downstream/${{ matrix.script }}