Factory System

The factory system provides a centralized, reflection-based approach to creating instances of both Target and ToolResponseGenerator from configuration.

Overview

The new factory system is located in src/mcp_kit/factory.py and replaces the previous manual factory methods with a more generic, reflection-based approach.

Core Components

create_object_from_config()

The generic factory function that can create any object type from configuration using reflection.

Parameters:

• config: Configuration object with a 'type' field
• get_class_name: Function that converts type string to class name
• get_module_name: Function that converts type string to module name
• object_type_name: Name of object type for error messages

create_target_from_config()

Factory function specifically for creating Target instances.

Example:

from src.mcp_kit.factory import create_target_from_config

config = {
    "type": "mcp",
    "name": "example-server",
    "url": "http://localhost:8080/mcp"
}
target = create_target_from_config(config)

create_response_generator_from_config()

Factory function specifically for creating ToolResponseGenerator instances.

Example:

from src.mcp_kit.factory import create_response_generator_from_config

config = {
    "type": "llm",
    "model": "gpt-4"
}
generator = create_response_generator_from_config(config)

Naming Conventions

Targets

• Configuration type: "mcp" → Class: McpTarget → Module: src.mcp_kit.targets.mcp_target
• Configuration type: "oas" → Class: OasTarget → Module: src.mcp_kit.targets.oas_target
• Configuration type: "mocked" → Class: MockedTarget → Module: src.mcp_kit.targets.mocked_target

Response Generators

• Configuration type: "random" → Class: RandomResponseGenerator → Module: src.mcp_kit.generators
• Configuration type: "llm" → Class: LLMResponseGenerator → Module: src.mcp_kit.generators

Benefits

1. Eliminates Manual Factories: No need to manually update factory methods when adding new types
2. Consistent Error Messages: Standardized error handling across all object types
3. Type Safety: Proper type hints and runtime checking
4. Extensibility: Easy to add new object types without modifying existing factory code
5. Reduced Circular Imports: Centralized factory prevents circular import issues

Migration

The refactoring maintains backward compatibility:

• All existing from_config() methods continue to work
• Import paths have been updated from src.mcp_kit.targets.factory to src.mcp_kit.factory
• Error messages have been standardized but tests have been updated accordingly

Adding New Types

To add a new target type:

1. Create the class following the naming convention (e.g., NewTarget)
2. Implement the from_config() class method
3. Place it in the appropriate module (e.g., src.mcp_kit.targets.new_target)
4. The factory will automatically discover and instantiate it

To add a new generator type:

1. Create the class following the naming convention (e.g., NewResponseGenerator)
2. Implement the from_config() class method
3. Place it in src.mcp_kit.generators
4. The factory will automatically discover and instantiate it