feat(integration-tests): Add integration tests for MCP server

Author: All-less

integration-tests/.pytest.ini

@@ -6,6 +6,7 @@ addopts =
     --strict-config
     --strict-markers
     --verbose
+    -m "not mcp"
 env =
     D:CLP_BUILD_DIR=../build
     D:CLP_CORE_BINS_DIR=../build/core
@@ -18,3 +19,4 @@ markers =
     clp: mark tests that use the CLP storage engine
     clp_s: mark tests that use the CLP-S storage engine
     core: mark tests that test the CLP core binaries
+    mcp: mark tests that test the MCP server

integration-tests/pyproject.toml

@@ -21,6 +21,8 @@ dev = [
     "ruff>=0.11.12",
     "pytest>=8.4.1",
     "pytest-env>=1.1.5",
+    "pytest-asyncio>=1.2.0",
+    "fastmcp>=2.12.4",
 ]
 
 [tool.mypy]

integration-tests/tests/test_mcp_server.py

@@ -0,0 +1,165 @@
+"""
+The integration tests for the CLP MCP server.
+
+IMPORTANT: These tests are designed to be run **manually** against a deployed CLP package.
+We will migrate them to automated tests when the test environment includes docker compose.
+
+### Environment Setup
+
+Deploy the CLP package with MCP server. The test suites assume the  MCP server is accessible
+at http://0.0.0.0:8000/mcp. If the MCP server is hosted at a different address, update the
+`MCP_SERVER_ENDPOINT` variable below accordingly.
+
+### Log Dataset
+
+The test dataset is taken from the `HDFS-11896` case study. To access the logs, visit the
+repository [y-scope/agent-dev](https://github.com/y-scope/agent-dev) and follow the instructions
+from `case-study/sync-logs-to-r2.sh`. The log file is located in `CLODS/HDFS/HDFS-11896/json`.
+Use the instructions below to ingest the logs into CLP package:
+```
+gzip -d CLODS/HDFS/HDFS-11896/json/hadoop-dn1__logs__hadoop.jsonl.gz
+sbin/compress.sh --timestamp-key ts CLODS/HDFS/HDFS-11896/json/hadoop-dn1__logs__hadoop.jsonl
+```
+
+### Running Tests
+
+The tests in this suite are skipped by default because they require a manually deployed CLP package
+with MCP server enabled. (The skipping is done by setting `-m "not mcp"` in `.pytest.ini`.) To run
+them, execute the following command in the terminal:
+```
+pytest -m mcp tests/test_mcp_server.py
+```
+"""
+
+import pytest
+from fastmcp import Client
+
+MCP_SERVER_ENDPOINT = "http://0.0.0.0:8000/mcp"
+
+
+@pytest.mark.mcp
+@pytest.mark.asyncio
+async def test_get_instructions() -> None:
+    """Tests the get_instructions tool."""
+    async with Client(MCP_SERVER_ENDPOINT) as client:
+        res = await client.call_tool("get_instructions")
+        assert isinstance(res.data, str)
+
+
+@pytest.mark.mcp
+@pytest.mark.asyncio
+async def test_search_by_kql() -> None:
+    """Tests the search_by_kql tool."""
+    async with Client(MCP_SERVER_ENDPOINT) as client:
+        await client.call_tool("get_instructions")
+
+        query = "*filter*"
+        result = await client.call_tool("search_by_kql", {"kql_query": query})
+
+        assert "items" in result.data
+        assert isinstance(result.data["items"], list)
+        assert "num_total_items" in result.data
+        assert "num_total_pages" in result.data
+        assert "num_items_per_page" in result.data
+        assert "has_next" in result.data
+        assert "has_previous" in result.data
+
+
+@pytest.mark.mcp
+@pytest.mark.asyncio
+async def test_get_nth_page() -> None:
+    """Tests the get_nth_page tool."""
+    async with Client(MCP_SERVER_ENDPOINT) as client:
+        await client.call_tool("get_instructions")
+
+        query = "*filter*"
+        await client.call_tool("search_by_kql", {"kql_query": query})
+
+        result = await client.call_tool("get_nth_page", {"page_index": 1})
+        assert "items" in result.data
+        assert isinstance(result.data["items"], list)
+        assert "num_total_items" in result.data
+        assert "num_total_pages" in result.data
+        assert "num_items_per_page" in result.data
+        assert "has_next" in result.data
+        assert "has_previous" in result.data
+
+
+@pytest.mark.mcp
+class TestSearchWithTimestamp:
+    """Tests the search_by_kql_with_timestamp_range tool."""
+
+    @pytest.mark.asyncio
+    async def test_success_case(self) -> None:
+        """Tests the success case of the search_by_kql_with_timestamp_range tool."""
+        async with Client(MCP_SERVER_ENDPOINT) as client:
+            await client.call_tool("get_instructions")
+
+            query = "*filter*"
+            result = await client.call_tool(
+                "search_by_kql_with_timestamp_range",
+                {
+                    "kql_query": query,
+                    "formatted_begin_timestamp": "2025-08-27T15:35:30.000Z",
+                    "formatted_end_timestamp": "2025-08-27T15:35:50.000Z",
+                },
+            )
+            assert "items" in result.data
+            assert isinstance(result.data["items"], list)
+            assert "num_total_items" in result.data
+            assert "num_total_pages" in result.data
+            assert "num_items_per_page" in result.data
+            assert "has_next" in result.data
+            assert "has_previous" in result.data
+
+    @pytest.mark.asyncio
+    async def test_invalid_timestamps(self) -> None:
+        """Tests the search_by_kql_with_timestamp_range tool with invalid timestamps."""
+        async with Client(MCP_SERVER_ENDPOINT) as client:
+            await client.call_tool("get_instructions")
+
+            query = "*filter*"
+            result = await client.call_tool(
+                "search_by_kql_with_timestamp_range",
+                {
+                    "kql_query": query,
+                    "formatted_begin_timestamp": "2025-08-27T15:35:55.000Z",
+                    "formatted_end_timestamp": "2025-08-27T15:35:50.000Z",
+                },
+            )
+            assert "Error" in result.data
+
+    @pytest.mark.asyncio
+    async def test_query_failure(self) -> None:
+        """Tests the search_by_kql_with_timestamp_range tool with a query that is killed."""
+        async with Client(MCP_SERVER_ENDPOINT) as client:
+            await client.call_tool("get_instructions")
+
+            query = "*filter*"
+            result = await client.call_tool(
+                "search_by_kql_with_timestamp_range",
+                {
+                    "kql_query": query,
+                    # This test (ab)uses a design in CLP: when the begin timestamp is set before
+                    # Unix epoch, the query will be killed. It works as of Oct. 22, 2025. The
+                    # future versions of CLP may change this behavior.
+                    "formatted_begin_timestamp": "1970-01-01T00:00:00.000Z",
+                    "formatted_end_timestamp": "1970-01-02T00:00:00.000Z",
+                },
+            )
+            assert "Error" in result.data
+
+
+@pytest.mark.mcp
+@pytest.mark.asyncio
+async def test_log_link() -> None:
+    """Tests that the search results contain log links."""
+    async with Client(MCP_SERVER_ENDPOINT) as client:
+        await client.call_tool("get_instructions")
+
+        query = "*error*"
+        result = await client.call_tool("search_by_kql", {"kql_query": query})
+
+        for item in result.data["items"]:
+            assert "link" in item
+