test: add unit tests of the app (#305)

* test: add unit tests in server

* test: add unit tests of app.py in server

* test: reformat the codes

* test: add more tests to cover the exception part

* test: add more tests on the server app part

* fix: don't show the detail exception to the client

* test: try to fix the CI test

* fix: keep the TTS API call without exposure information

* Fixed the unit test errors

* Fixed the lint error

tests/unit/server/test_mcp_request.py

@@ -0,0 +1,73 @@
+# Copyright (c) 2025 Bytedance Ltd. and/or its affiliates
+# SPDX-License-Identifier: MIT
+
+import pytest
+from pydantic import ValidationError
+from src.server.mcp_request import MCPServerMetadataRequest, MCPServerMetadataResponse
+
+
+def test_mcp_server_metadata_request_required_fields():
+    # 'transport' is required
+    req = MCPServerMetadataRequest(transport="stdio")
+    assert req.transport == "stdio"
+    assert req.command is None
+    assert req.args is None
+    assert req.url is None
+    assert req.env is None
+    assert req.timeout_seconds is None
+
+
+def test_mcp_server_metadata_request_optional_fields():
+    req = MCPServerMetadataRequest(
+        transport="sse",
+        command="run",
+        args=["--foo", "bar"],
+        url="http://localhost:8080",
+        env={"FOO": "BAR"},
+        timeout_seconds=30,
+    )
+    assert req.transport == "sse"
+    assert req.command == "run"
+    assert req.args == ["--foo", "bar"]
+    assert req.url == "http://localhost:8080"
+    assert req.env == {"FOO": "BAR"}
+    assert req.timeout_seconds == 30
+
+
+def test_mcp_server_metadata_request_missing_transport():
+    with pytest.raises(ValidationError):
+        MCPServerMetadataRequest()
+
+
+def test_mcp_server_metadata_response_required_fields():
+    resp = MCPServerMetadataResponse(transport="stdio")
+    assert resp.transport == "stdio"
+    assert resp.command is None
+    assert resp.args is None
+    assert resp.url is None
+    assert resp.env is None
+    assert resp.tools == []
+
+
+def test_mcp_server_metadata_response_optional_fields():
+    resp = MCPServerMetadataResponse(
+        transport="sse",
+        command="run",
+        args=["--foo", "bar"],
+        url="http://localhost:8080",
+        env={"FOO": "BAR"},
+        tools=["tool1", "tool2"],
+    )
+    assert resp.transport == "sse"
+    assert resp.command == "run"
+    assert resp.args == ["--foo", "bar"]
+    assert resp.url == "http://localhost:8080"
+    assert resp.env == {"FOO": "BAR"}
+    assert resp.tools == ["tool1", "tool2"]
+
+
+def test_mcp_server_metadata_response_tools_default_factory():
+    resp1 = MCPServerMetadataResponse(transport="stdio")
+    resp2 = MCPServerMetadataResponse(transport="stdio")
+    resp1.tools.append("toolA")
+    assert resp2.tools == []  # Should not share list between instances