superset2/tests/unit_tests/mcp_service/test_mcp_caching.py

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"""Tests for MCP response caching middleware."""

from unittest.mock import MagicMock, patch

from superset.mcp_service.caching import _build_caching_settings


def test_build_caching_settings_empty_config():
    """Empty config returns empty settings."""
    result = _build_caching_settings({})
    assert result == {}


def test_build_caching_settings_list_ttls():
    """List operation TTLs are mapped to settings."""
    config = {
        "list_tools_ttl": 300,
        "list_resources_ttl": 300,
        "list_prompts_ttl": 300,
    }
    result = _build_caching_settings(config)

    assert result["list_tools_settings"] == {"ttl": 300}
    assert result["list_resources_settings"] == {"ttl": 300}
    assert result["list_prompts_settings"] == {"ttl": 300}


def test_build_caching_settings_item_ttls():
    """Individual item TTLs are mapped to settings."""
    config = {
        "read_resource_ttl": 3600,
        "get_prompt_ttl": 3600,
    }
    result = _build_caching_settings(config)

    assert result["read_resource_settings"] == {"ttl": 3600}
    assert result["get_prompt_settings"] == {"ttl": 3600}


def test_build_caching_settings_call_tool_with_exclusions():
    """Call tool settings include TTL and exclusions."""
    config = {
        "call_tool_ttl": 3600,
        "excluded_tools": ["execute_sql", "generate_chart"],
    }
    result = _build_caching_settings(config)

    assert result["call_tool_settings"] == {
        "ttl": 3600,
        "excluded_tools": ["execute_sql", "generate_chart"],
    }


def test_create_response_caching_middleware_returns_none_when_disabled():
    """Caching middleware returns None when disabled in config."""
    mock_flask_app = MagicMock()
    mock_flask_app.config.get.return_value = {"enabled": False}

    with patch(
        "superset.mcp_service.flask_singleton.get_flask_app",
        return_value=mock_flask_app,
    ):
        with patch("flask.has_app_context", return_value=True):
            from superset.mcp_service.caching import create_response_caching_middleware

            result = create_response_caching_middleware()

            assert result is None


def test_create_response_caching_middleware_returns_none_when_no_prefix():
    """Caching middleware returns None when CACHE_KEY_PREFIX is not set."""
    mock_flask_app = MagicMock()
    mock_flask_app.config.get.return_value = {
        "enabled": True,
        "CACHE_KEY_PREFIX": None,
    }

    with patch(
        "superset.mcp_service.flask_singleton.get_flask_app",
        return_value=mock_flask_app,
    ):
        with patch("flask.has_app_context", return_value=True):
            from superset.mcp_service.caching import create_response_caching_middleware

            result = create_response_caching_middleware()

            assert result is None


def test_create_response_caching_middleware_creates_middleware():
    """Caching middleware is created when properly configured."""
    mock_flask_app = MagicMock()
    mock_flask_app.config.get.return_value = {
        "enabled": True,
        "CACHE_KEY_PREFIX": "mcp_cache_v1_",
        "list_tools_ttl": 300,
    }

    mock_store = MagicMock()
    mock_middleware = MagicMock()

    with patch(
        "superset.mcp_service.flask_singleton.get_flask_app",
        return_value=mock_flask_app,
    ):
        with patch("flask.has_app_context", return_value=True):
            with patch(
                "superset.mcp_service.caching.get_mcp_store", return_value=mock_store
            ):
                with patch(
                    "fastmcp.server.middleware.caching.ResponseCachingMiddleware",
                    return_value=mock_middleware,
                ) as mock_middleware_class:
                    from superset.mcp_service.caching import (
                        create_response_caching_middleware,
                    )

                    result = create_response_caching_middleware()

                    assert result is mock_middleware
                    # Verify middleware was created with store and settings
                    mock_middleware_class.assert_called_once()
                    call_kwargs = mock_middleware_class.call_args[1]
                    assert call_kwargs["cache_storage"] is mock_store
                    assert call_kwargs["list_tools_settings"] == {"ttl": 300}