Custom components are the building blocks that allow you to extend SmartGraph’s functionality and create tailored solutions for your specific needs. In this guide, we’ll explore the various ways to create custom components and dive into the options available to you.

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Basic Custom Component

At its core, a custom component in SmartGraph is a class that inherits from ReactiveComponent. Here’s a basic template: 
from smartgraph import ReactiveComponent

class MyCustomComponent(ReactiveComponent):
    def __init__(self, name: str):
        super().__init__(name)

    async def process(self, input_data: Any) -> Any:
        # Process the input data
        result = self.custom_logic(input_data)
        return result

    def custom_logic(self, data):
        # Implement your custom logic here
        return data
The key method to implement is process, which defines how your component handles input data.

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State Management in Custom Components

You can add state to your custom components using the built-in state management methods: 
class StatefulComponent(ReactiveComponent):
    def __init__(self, name: str):
        super().__init__(name)
        self.create_state("my_state", initial_value=0)

    async def process(self, input_data: Any) -> Any:
        current_state = self.get_state("my_state").value
        new_state = current_state + 1
        self.update_state("my_state", new_state)
        return f"Processed {input_data} (State: {new_state})"

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Error Handling

Implement robust error handling in your custom components: 
class ErrorHandlingComponent(ReactiveComponent):
    async def process(self, input_data: Any) -> Any:
        try:
            # Process data
            result = self.risky_operation(input_data)
            return result
        except Exception as e:
            self.error.on_next(e)
            return {"error": str(e)}

    def risky_operation(self, data):
        # Implement potentially risky logic here
        pass

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Asynchronous Components

For components that need to perform asynchronous operations: 
import aiohttp

class AsyncAPIComponent(ReactiveComponent):
    async def process(self, input_data: Any) -> Any:
        async with aiohttp.ClientSession() as session:
            async with session.get(f"https://api.example.com/{input_data}") as response:
                return await response.json()

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Components with External Dependencies

If your component relies on external libraries or services: 
import openai

class OpenAIComponent(ReactiveComponent):
    def __init__(self, name: str, api_key: str):
        super().__init__(name)
        openai.api_key = api_key

    async def process(self, input_data: Any) -> Any:
        response = await openai.ChatCompletion.acreate(
            model="gpt-3.5-turbo",
            messages=[{"role": "user", "content": input_data}]
        )
        return response.choices[0].message.content

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Branching Components

Create components that can direct flow based on input: 
class BranchingComponent(ReactiveComponent):
    def __init__(self, name: str, condition_func):
        super().__init__(name)
        self.condition_func = condition_func

    async def process(self, input_data: Any) -> Any:
        if self.condition_func(input_data):
            return {"branch": "true", "data": input_data}
        else:
            return {"branch": "false", "data": input_data}

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Components with Internal Buffers

For components that need to accumulate data: 
class BufferingComponent(ReactiveComponent):
    def __init__(self, name: str, buffer_size: int):
        super().__init__(name)
        self.create_state("buffer", [])
        self.buffer_size = buffer_size

    async def process(self, input_data: Any) -> Any:
        buffer = self.get_state("buffer").value
        buffer.append(input_data)
        if len(buffer) > self.buffer_size:
            buffer = buffer[-self.buffer_size:]
        self.update_state("buffer", buffer)
        return {"buffer_content": buffer, "buffer_size": len(buffer)}

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Components with Initialization and Cleanup

For components that need setup and teardown operations: 
class DatabaseComponent(ReactiveComponent):
    def __init__(self, name: str, db_url: str):
        super().__init__(name)
        self.db_url = db_url
        self.db_connection = None

    async def initialize(self):
        # Set up database connection
        self.db_connection = await create_db_connection(self.db_url)

    async def process(self, input_data: Any) -> Any:
        # Use self.db_connection to interact with the database
        result = await self.db_connection.query(input_data)
        return result

    async def cleanup(self):
        # Close database connection
        if self.db_connection:
            await self.db_connection.close()

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Composable Components

Create higher-order components by composing existing ones: 
class ComposedComponent(ReactiveComponent):
    def __init__(self, name: str):
        super().__init__(name)
        self.sub_component1 = SubComponent1("Sub1")
        self.sub_component2 = SubComponent2("Sub2")

    async def process(self, input_data: Any) -> Any:
        intermediate_result = await self.sub_component1.process(input_data)
        final_result = await self.sub_component2.process(intermediate_result)
        return final_result

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Best Practices for Custom Components

  1. Single Responsibility: Each component should have a single, well-defined purpose.
  2. Input Validation: Validate input data at the beginning of the process method.
  3. Error Handling: Use try-except blocks to handle potential errors gracefully.
  4. State Management: Use the built-in state management methods for maintaining component state.
  5. Asynchronous Design: Utilize async/await for any I/O-bound operations.
  6. Logging: Implement logging to aid in debugging and monitoring.
  7. Type Hinting: Use type hints to improve code readability and catch potential type-related errors.
  8. Documentation: Provide clear docstrings explaining the component’s purpose and usage.

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Conclusion

Creating custom components in SmartGraph allows you to extend its functionality to meet your specific needs. Whether you’re integrating with external APIs, implementing complex business logic, or creating reusable building blocks for your AI pipelines, custom components provide the flexibility and power to build sophisticated AI applications.

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Next Steps

Now that you’ve learned how to create custom components, explore how to debug and test your SmartGraph applications in the Debugging and Testing section.