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🐛 fix(mcp): 统一元数据响应 JSON 序列化 #158

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Merged
ZhaoXingPeng merged 1 commit into from
Sep 9, 2026
Merged

🐛 fix(mcp): 统一元数据响应 JSON 序列化 #158

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23 changes: 13 additions & 10 deletions src/dbjavagenix/database/mcp_tools.py
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Original file line number Diff line number Diff line change
Expand Up @@ -75,6 +75,11 @@ def _query_result_json_default(value: object) -> object:
raise TypeError(f"Object of type {type(value).__name__} is not JSON serializable")


def _json_dumps(value: object) -> str:
"""Serialize MCP payloads with the same driver-value rules as query results."""
return json.dumps(value, ensure_ascii=False, default=_query_result_json_default)


def _resolve_codegen_output_path(base_dir: Path, relative_path: object) -> Path:
"""Resolve a generated filename while keeping it inside its output directory."""
if not isinstance(relative_path, str) or not relative_path.strip():
Expand Down Expand Up @@ -1047,9 +1052,7 @@ async def handle_db_query_execute(arguments: Dict[str, Any]) -> List[TextContent
else:
result_text = "Query executed successfully. No rows returned."

result_text += "\n\nRaw Response: " + json.dumps(
response, ensure_ascii=False, default=_query_result_json_default
)
result_text += "\n\nRaw Response: " + _json_dumps(response)

return [TextContent(
type="text",
Expand Down Expand Up @@ -1238,7 +1241,7 @@ async def handle_db_table_describe(arguments: Dict[str, Any]) -> List[TextConten
for imp in sorted(java_imports):
result_text += f"import {imp};\n"

result_text += f"\nRaw Response: {json.dumps(response, ensure_ascii=False)}"
result_text += f"\nRaw Response: {_json_dumps(response)}"

return [TextContent(
type="text",
Expand Down Expand Up @@ -1374,7 +1377,7 @@ async def handle_db_table_columns(arguments: Dict[str, Any]) -> List[TextContent
result_text += f" Comment: {row['COLUMN_COMMENT']}\n"
result_text += "\n"

result_text += f"Raw Response: {json.dumps(response, ensure_ascii=False)}"
result_text += f"Raw Response: {_json_dumps(response)}"

return [TextContent(
type="text",
Expand Down Expand Up @@ -1476,7 +1479,7 @@ async def handle_db_table_primary_keys(arguments: Dict[str, Any]) -> List[TextCo
else:
result_text = f"No primary keys found for table {database}.{table}\n"

result_text += f"\nRaw Response: {json.dumps(response, ensure_ascii=False)}"
result_text += f"\nRaw Response: {_json_dumps(response)}"

return [TextContent(
type="text",
Expand Down Expand Up @@ -1618,7 +1621,7 @@ async def handle_db_table_foreign_keys(arguments: Dict[str, Any]) -> List[TextCo
else:
result_text = f"No foreign keys found for table {database}.{table}\n"

result_text += f"Raw Response: {json.dumps(response, ensure_ascii=False)}"
result_text += f"Raw Response: {_json_dumps(response)}"

return [TextContent(
type="text",
Expand Down Expand Up @@ -1774,7 +1777,7 @@ async def handle_db_table_indexes(arguments: Dict[str, Any]) -> List[TextContent
else:
result_text = f"No indexes found for table {database}.{table}\n"

result_text += f"Raw Response: {json.dumps(response, ensure_ascii=False)}"
result_text += f"Raw Response: {_json_dumps(response)}"

return [TextContent(
type="text",
Expand Down Expand Up @@ -2040,8 +2043,8 @@ async def handle_db_codegen_analyze(arguments: Dict[str, Any]) -> List[TextConte
result_text += f" Has Primary Key: {'Yes' if context.get('primaryKey') else 'No'}\n"

# Keep a structured payload for non-MCP callers such as the CLI.
result_text += "\n\nRaw Response: " + json.dumps(
{"success": True, **analysis_result}, ensure_ascii=False
result_text += "\n\nRaw Response: " + _json_dumps(
{"success": True, **analysis_result}
)

return [TextContent(
Expand Down
149 changes: 149 additions & 0 deletions tests/unit/test_mcp_error_json.py
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Original file line number Diff line number Diff line change
Expand Up @@ -140,6 +140,155 @@ async def test_query_execute_serializes_real_driver_value_types(monkeypatch):
}


@pytest.mark.asyncio
async def test_metadata_handlers_serialize_driver_value_types(monkeypatch):
config = SimpleNamespace(type=DatabaseType.POSTGRESQL, database="app")

class Introspector:
def __init__(self, _manager):
pass

def get_config(self, _connection_id):
return config

def describe_table(self, _connection_id, _table, _schema):
return {
"name": "events",
"schema": "public",
"comment": datetime(2026, 9, 8, 10, 0, tzinfo=timezone.utc),
"columns": [
{
"name": "amount",
"type": "numeric",
"column_type": "numeric(10,2)",
"nullable": False,
"default_value": Decimal("12.30"),
"comment": UUID("12345678-1234-5678-1234-567812345678"),
"primary_key": False,
"precision": 10,
"scale": 2,
"max_length": None,
}
],
}

def get_columns(self, _connection_id, _table, _schema):
return [
{
"name": "amount",
"type": "numeric",
"column_type": "numeric(10,2)",
"nullable": False,
"default_value": memoryview(b"view"),
"comment": "created",
"precision": 10,
"scale": 2,
"max_length": None,
}
]

def get_primary_keys(self, _connection_id, _table, _schema):
return ["id"]

def get_foreign_keys(self, _connection_id, _table, _schema):
return [
{
"column_name": "owner_id",
"referenced_table": "users",
"referenced_column": "id",
"constraint_name": "events_owner_fk",
}
]

def get_indexes(self, _connection_id, _table, _schema):
return [
{
"key_name": "events_amount_idx",
"column_name": "amount",
"seq_in_index": 1,
"unique": False,
"index_type": "btree",
}
]

monkeypatch.setattr(mcp_tools, "DatabaseIntrospector", Introspector)
monkeypatch.setattr(
mcp_tools.connection_manager,
"get_connection_info",
lambda _id: config,
)
common = {
"connection_id": "pg-1",
"database": "app",
"table": "events",
"schema": "public",
}

describe = await mcp_tools.handle_db_table_describe(common)
columns = await mcp_tools.handle_db_table_columns(common)
primary_keys = await mcp_tools.handle_db_table_primary_keys(common)
foreign_keys = await mcp_tools.handle_db_table_foreign_keys(common)
indexes = await mcp_tools.handle_db_table_indexes(common)

assert _raw_payload(describe)["columns"][0]["default_value"] == "12.30"
assert _raw_payload(describe)["comment"] == "2026-09-08T10:00:00+00:00"
assert _raw_payload(columns)["columns"][0]["COLUMN_DEFAULT"] == {
"encoding": "base64",
"data": "dmlldw==",
}
assert _raw_payload(columns)["columns"][0]["COLUMN_COMMENT"] == "created"
assert _raw_payload(primary_keys)["primary_keys"] == ["id"]
assert _raw_payload(foreign_keys)["foreign_keys"][0]["references_table"] == "users"
assert _raw_payload(indexes)["indexes"][0]["name"] == "events_amount_idx"


@pytest.mark.asyncio
async def test_codegen_analysis_raw_response_serializes_driver_values(monkeypatch):
class Analyzer:
def __init__(self, _manager):
pass

async def analyze_table_for_codegen(self, *_args, **_kwargs):
return {
"table_name": "events",
"table_info": {
"name": "events",
"comment": "event table",
"columns": [
{
"name": "amount",
"type": "numeric",
"default_value": Decimal("12.30"),
}
],
},
"template_context": {
"columns": [{"javaType": "BigDecimal"}],
"className": "Event",
"lowerCaseName": "event",
"hasDateField": False,
"hasBigDecimalField": True,
"primaryKey": "id",
},
"java_types": ["BigDecimal"],
"imports_needed": [],
"relationships": {"primary_keys": ["id"], "foreign_keys": [], "indexes": []},
}

monkeypatch.setattr("dbjavagenix.database.codegen_tools.CodegenAnalyzer", Analyzer)
monkeypatch.setattr(
mcp_tools.connection_manager,
"get_connection_info",
lambda _id: SimpleNamespace(type=DatabaseType.POSTGRESQL, database="app"),
)

response = await mcp_tools.handle_db_codegen_analyze(
{"connection_id": "pg-1", "table_name": "events"}
)

assert _raw_payload(response)["table_info"]["columns"][0]["default_value"] == "12.30"


def test_query_result_json_default_rejects_unknown_object():
class UnknownDriverValue:
pass
Expand Down
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