MCP Demo Server

""" Unit tests for the MCP Demo Server. Tests cover: - Tool functionality (calculator, file operations, weather, timestamp) - Resource reading - Prompt generation - Error handling - Input validation """ import json import pytest from pathlib import Path from datetime import datetime from mcp_demo.server import MCPDemoServer, CalculatorInput, FileOperationInput, WeatherInput @pytest.fixture async def server(): """Create a test server instance.""" return MCPDemoServer(name="test-server") class TestServerInitialization: """Test server initialization and setup.""" @pytest.mark.asyncio async def test_server_creation(self, server): """Test that server is created successfully.""" assert server is not None assert server.name == "test-server" assert server.server is not None @pytest.mark.asyncio async def test_handlers_registered(self, server): """Test that all handlers are registered.""" # Handlers should be set up during initialization assert server.server._request_handlers is not None class TestTools: """Test all tool implementations.""" @pytest.mark.asyncio async def test_list_tools(self, server): """Test listing available tools.""" tools = await server.list_tools() assert len(tools) == 4 tool_names = [tool.name for tool in tools] assert "calculator" in tool_names assert "file_operations" in tool_names assert "weather" in tool_names assert "timestamp" in tool_names @pytest.mark.asyncio async def test_calculator_add(self, server): """Test calculator addition.""" result = await server.call_tool( "calculator", {"operation": "add", "a": 10, "b": 20} ) assert len(result) == 1 assert "30" in result[0].text @pytest.mark.asyncio async def test_calculator_subtract(self, server): """Test calculator subtraction.""" result = await server.call_tool( "calculator", {"operation": "subtract", "a": 50, "b": 20} ) assert len(result) == 1 assert "30" in result[0].text @pytest.mark.asyncio async def test_calculator_multiply(self, server): """Test calculator multiplication.""" result = await server.call_tool( "calculator", {"operation": "multiply", "a": 6, "b": 7} ) assert len(result) == 1 assert "42" in result[0].text @pytest.mark.asyncio async def test_calculator_divide(self, server): """Test calculator division.""" result = await server.call_tool( "calculator", {"operation": "divide", "a": 100, "b": 4} ) assert len(result) == 1 assert "25" in result[0].text @pytest.mark.asyncio async def test_calculator_divide_by_zero(self, server): """Test calculator division by zero handling.""" result = await server.call_tool( "calculator", {"operation": "divide", "a": 10, "b": 0} ) assert len(result) == 1 assert "Division by zero" in result[0].text @pytest.mark.asyncio async def test_calculator_invalid_operation(self, server): """Test calculator with invalid operation.""" result = await server.call_tool( "calculator", {"operation": "power", "a": 2, "b": 3} ) assert len(result) == 1 assert "Error" in result[0].text or "Invalid" in result[0].text @pytest.mark.asyncio async def test_timestamp_iso(self, server): """Test timestamp tool with ISO format.""" result = await server.call_tool( "timestamp", {"format": "iso"} ) assert len(result) == 1 assert "iso" in result[0].text.lower() # Check that result contains a timestamp-like string assert any(char.isdigit() for char in result[0].text) @pytest.mark.asyncio async def test_timestamp_unix(self, server): """Test timestamp tool with Unix format.""" result = await server.call_tool( "timestamp", {"format": "unix"} ) assert len(result) == 1 assert "unix" in result[0].text.lower() assert any(char.isdigit() for char in result[0].text) @pytest.mark.asyncio async def test_timestamp_human(self, server): """Test timestamp tool with human-readable format.""" result = await server.call_tool( "timestamp", {"format": "human"} ) assert len(result) == 1 assert "human" in result[0].text.lower() assert any(char.isdigit() for char in result[0].text) @pytest.mark.asyncio async def test_weather_celsius(self, server): """Test weather tool with Celsius.""" result = await server.call_tool( "weather", {"city": "Tokyo", "units": "celsius"} ) assert len(result) == 1 assert "Tokyo" in result[0].text assert "°C" in result[0].text or "celsius" in result[0].text.lower() @pytest.mark.asyncio async def test_weather_fahrenheit(self, server): """Test weather tool with Fahrenheit.""" result = await server.call_tool( "weather", {"city": "New York", "units": "fahrenheit"} ) assert len(result) == 1 assert "New York" in result[0].text assert "°F" in result[0].text or "fahrenheit" in result[0].text.lower() @pytest.mark.asyncio async def test_file_operations_write_read(self, server, tmp_path): """Test file write and read operations.""" test_file = tmp_path / "test.txt" test_content = "Hello, MCP!" # Write file write_result = await server.call_tool( "file_operations", { "operation": "write", "path": str(test_file), "content": test_content } ) assert len(write_result) == 1 assert "Successfully wrote" in write_result[0].text # Read file read_result = await server.call_tool( "file_operations", { "operation": "read", "path": str(test_file) } ) assert len(read_result) == 1 assert test_content in read_result[0].text @pytest.mark.asyncio async def test_file_operations_exists(self, server, tmp_path): """Test file exists check.""" test_file = tmp_path / "exists_test.txt" test_file.write_text("test") result = await server.call_tool( "file_operations", { "operation": "exists", "path": str(test_file) } ) assert len(result) == 1 assert "True" in result[0].text @pytest.mark.asyncio async def test_file_operations_list(self, server, tmp_path): """Test directory listing.""" # Create some test files (tmp_path / "file1.txt").write_text("test1") (tmp_path / "file2.txt").write_text("test2") result = await server.call_tool( "file_operations", { "operation": "list", "path": str(tmp_path) } ) assert len(result) == 1 assert "file1.txt" in result[0].text assert "file2.txt" in result[0].text @pytest.mark.asyncio async def test_unknown_tool(self, server): """Test calling an unknown tool.""" result = await server.call_tool( "nonexistent_tool", {} ) assert len(result) == 1 assert "Error" in result[0].text or "Unknown" in result[0].text class TestResources: """Test resource functionality.""" @pytest.mark.asyncio async def test_list_resources(self, server): """Test listing available resources.""" resources = await server.list_resources() assert len(resources) == 3 resource_uris = [str(r.uri) for r in resources] assert "config://server/settings" in resource_uris assert "system://info" in resource_uris assert "docs://getting-started" in resource_uris @pytest.mark.asyncio async def test_read_config_resource(self, server): """Test reading server configuration resource.""" from pydantic import AnyUrl content = await server.read_resource(AnyUrl("config://server/settings")) assert content is not None config = json.loads(content) assert "server_name" in config assert config["server_name"] == "test-server" assert "version" in config assert "features" in config @pytest.mark.asyncio async def test_read_system_info_resource(self, server): """Test reading system information resource.""" from pydantic import AnyUrl content = await server.read_resource(AnyUrl("system://info")) assert content is not None info = json.loads(content) assert "os" in info assert "python_version" in info assert "working_directory" in info @pytest.mark.asyncio async def test_read_docs_resource(self, server): """Test reading documentation resource.""" from pydantic import AnyUrl content = await server.read_resource(AnyUrl("docs://getting-started")) assert content is not None assert "Getting Started" in content assert "TOOLS" in content assert "RESOURCES" in content assert "PROMPTS" in content @pytest.mark.asyncio async def test_read_unknown_resource(self, server): """Test reading an unknown resource.""" from pydantic import AnyUrl with pytest.raises(ValueError, match="Unknown resource"): await server.read_resource(AnyUrl("unknown://resource")) class TestPrompts: """Test prompt functionality.""" @pytest.mark.asyncio async def test_list_prompts(self, server): """Test listing available prompts.""" prompts = await server.list_prompts() assert len(prompts) == 3 prompt_names = [p.name for p in prompts] assert "code-review" in prompt_names assert "documentation" in prompt_names assert "debug-assistant" in prompt_names @pytest.mark.asyncio async def test_get_code_review_prompt(self, server): """Test getting code review prompt.""" result = await server.get_prompt( "code-review", {"language": "Python", "complexity": "simple"} ) assert result is not None assert len(result.messages) == 1 message_text = result.messages[0].content.text assert "Python" in message_text assert "Code Review" in message_text assert "Code Quality" in message_text @pytest.mark.asyncio async def test_get_documentation_prompt_api(self, server): """Test getting API documentation prompt.""" result = await server.get_prompt( "documentation", {"type": "api", "project_name": "Test Project"} ) assert result is not None assert len(result.messages) == 1 message_text = result.messages[0].content.text assert "Test Project" in message_text assert "API Documentation" in message_text @pytest.mark.asyncio async def test_get_documentation_prompt_user(self, server): """Test getting user documentation prompt.""" result = await server.get_prompt( "documentation", {"type": "user", "project_name": "My App"} ) assert result is not None assert len(result.messages) == 1 message_text = result.messages[0].content.text assert "My App" in message_text assert "User Guide" in message_text @pytest.mark.asyncio async def test_get_debug_assistant_prompt(self, server): """Test getting debug assistant prompt.""" error = "NullPointerException at line 42" result = await server.get_prompt( "debug-assistant", {"error_message": error} ) assert result is not None assert len(result.messages) == 1 message_text = result.messages[0].content.text assert error in message_text assert "Debug" in message_text assert "Steps" in message_text @pytest.mark.asyncio async def test_get_unknown_prompt(self, server): """Test getting an unknown prompt.""" with pytest.raises(ValueError, match="Unknown prompt"): await server.get_prompt("nonexistent-prompt", {}) class TestInputValidation: """Test input validation with Pydantic models.""" def test_calculator_input_validation(self): """Test calculator input model validation.""" # Valid input valid_input = CalculatorInput(operation="add", a=10, b=20) assert valid_input.operation == "add" assert valid_input.a == 10 assert valid_input.b == 20 # Test with missing required field with pytest.raises(Exception): CalculatorInput(operation="add", a=10) # Missing 'b' def test_file_operation_input_validation(self): """Test file operation input model validation.""" # Valid input valid_input = FileOperationInput(operation="read", path="/tmp/test.txt") assert valid_input.operation == "read" assert valid_input.path == "/tmp/test.txt" assert valid_input.content is None # With optional content write_input = FileOperationInput( operation="write", path="/tmp/test.txt", content="Hello" ) assert write_input.content == "Hello" def test_weather_input_validation(self): """Test weather input model validation.""" # Valid input with defaults valid_input = WeatherInput(city="Tokyo") assert valid_input.city == "Tokyo" assert valid_input.units == "celsius" # With custom units fahrenheit_input = WeatherInput(city="New York", units="fahrenheit") assert fahrenheit_input.units == "fahrenheit" class TestErrorHandling: """Test error handling throughout the server.""" @pytest.mark.asyncio async def test_tool_execution_error_handling(self, server): """Test that tool execution errors are caught and returned.""" # This should trigger error handling result = await server.call_tool( "calculator", {"operation": "invalid", "a": 1, "b": 2} ) assert len(result) == 1 assert "Error" in result[0].text or "Invalid" in result[0].text @pytest.mark.asyncio async def test_file_read_nonexistent(self, server): """Test reading a nonexistent file.""" result = await server.call_tool( "file_operations", { "operation": "read", "path": "/nonexistent/path/to/file.txt" } ) assert len(result) == 1 assert "Error" in result[0].text or "does not exist" in result[0].text if __name__ == "__main__": pytest.main([__file__, "-v"])