Feature Development

Feature Development

QQQ framework development is about extending the framework itself - adding new capabilities, modules, and core functionality. This guide shows you how to contribute to QQQ's evolution.

Framework Extension Philosophy

Core Framework Extensions

QQQ is designed to be extended at multiple levels:

• Core Actions: New action types and execution patterns
• Metadata System: New metadata types and relationships
• Validation Framework: Custom validation rules and plugins
• Scheduler System: New job types and execution engines
• Logging Framework: Custom log formats and handlers

Module System Extensions

QQQ's modular architecture allows you to add new capabilities:

• Backend Modules: New storage backends and data sources
• Middleware Extensions: New server types and protocols
• Frontend Components: New UI framework capabilities
• Language Support: New scripting and execution engines

Framework Development Workflow

1. Architecture Design

Before extending QQQ, understand the existing architecture:

# Study existing implementations
find qqq-backend-core/src -name "*.java" -exec grep -l "interface\|abstract class" {} \;

# Understand module patterns
grep -r "implements QBackendModuleInterface" qqq-backend-core/src/
grep -r "extends AbstractQActionFunction" qqq-backend-core/src/

# Review extension mechanisms
grep -r "QInstanceValidatorPluginInterface" qqq-backend-core/src/
grep -r "MetaDataProducerInterface" qqq-backend-core/src/

Design Questions:

• What framework capability are you adding?
• How does it integrate with existing QQQ systems?
• What interfaces need to be extended?
• What metadata changes are required?

2. Core Framework Extensions

Adding new capabilities to QQQ's core:

New Action Types

// ✅ CORRECT - Extending QQQ's action framework
public class StreamingAction extends AbstractQActionFunction<StreamingInput, StreamingOutput>
{
   private static final QLogger LOG = QLogger.getLogger(StreamingAction.class);

   @Override
   public StreamingOutput execute(StreamingInput input) throws QException
   {
      // New streaming capability for QQQ
      StreamingProcessor processor = new StreamingProcessor();
      return processor.processStream(input.getDataStream());
   }
}

New Metadata Types

// ✅ CORRECT - Extending QQQ's metadata system
public class QStreamingMetaData extends AbstractMetaData
{
   private String streamType;
   private int bufferSize;
   private boolean asyncProcessing;
   
   // Metadata for streaming configuration
}

New Validation Plugins

// ✅ CORRECT - Extending QQQ's validation system
public class StreamingValidatorPlugin implements QInstanceValidatorPluginInterface<QStreamingMetaData>
{
   @Override
   public void validate(QStreamingMetaData metadata) throws QException
   {
      // Validate streaming configuration
      if (metadata.getBufferSize() <= 0)
      {
         throw new QException("Buffer size must be positive");
      }
   }
}

3. Backend Module Extensions

Adding new storage backends and data processing engines:

New Storage Backend

// ✅ CORRECT - New QQQ backend module
public class RedisBackendModule implements QBackendModuleInterface
{
   @Override
   public String getBackendType()
   {
      return "redis";
   }
   
   @Override
   public Class<? extends QBackendMetaData> getBackendMetaDataClass()
   {
      return RedisBackendMetaData.class;
   }
   
   // Implement required interfaces
}

New Data Processing Engine

// ✅ CORRECT - New QQQ processing capability
public class GraphQLBackendModule implements QBackendModuleInterface
{
   @Override
   public String getBackendType()
   {
      return "graphql";
   }
   
   // GraphQL-specific implementation
}

4. Middleware Extensions

Adding new server types and protocol support:

New HTTP Server Type

// ✅ CORRECT - New QQQ middleware type
public class QuarkusMiddlewareModule implements QMiddlewareInterface
{
   @Override
   public void start(QInstance instance)
   {
      // Start Quarkus server with QQQ integration
   }
   
   @Override
   public void stop()
   {
      // Stop Quarkus server
   }
}

New Protocol Support

// ✅ CORRECT - New QQQ protocol support
public class GrpcMiddlewareModule implements QMiddlewareInterface
{
   @Override
   public void start(QInstance instance)
   {
      // Start gRPC server with QQQ action exposure
   }
}

5. Frontend Framework Extensions

Adding new UI framework capabilities:

New Widget Framework

// ✅ CORRECT - New QQQ frontend capability
public class ChartWidgetFramework implements QWidgetFrameworkInterface
{
   @Override
   public QWidget createWidget(QWidgetMetaData metadata)
   {
      // Create chart widget based on metadata
      return new ChartWidget(metadata);
   }
}

New Form Components

// ✅ CORRECT - New QQQ UI component
public class RichTextEditorWidget extends QWidget
{
   @Override
   public void render(QWidgetContext context)
   {
      // Render rich text editor with QQQ integration
   }
}

Integration and Registration

Module Registration

New modules must register themselves with QQQ:

// ✅ CORRECT - Self-registering module
public class MyNewModule implements QBackendModuleInterface
{
   static
   {
      // Register with QQQ's module system
      QBackendModuleDispatcher.register(new MyNewModule());
   }
   
   // Implementation...
}

Metadata Integration

New metadata types must integrate with QQQ's metadata system:

// ✅ CORRECT - Metadata producer for new types
public class MyMetaDataProducer implements MetaDataProducerInterface
{
   @Override
   public void produce(QInstance instance)
   {
      // Add new metadata to QInstance
      instance.addMetaData(new MyMetaData());
   }
}

Testing Framework Extensions

Unit Testing

Test new framework capabilities in isolation:

@Test
public void testNewActionType()
{
   // Test new action type
   StreamingAction action = new StreamingAction();
   StreamingInput input = new StreamingInput();
   StreamingOutput output = action.execute(input);
   
   // Verify behavior
   assertThat(output).isNotNull();
}

Integration Testing

Test new capabilities with existing QQQ systems:

@Test
public void testNewModuleIntegration()
{
   // Test new module with QQQ core
   QInstance instance = TestUtils.defineInstance();
   instance.addBackend(new MyNewBackend());
   
   // Verify integration
   assertThat(instance.getBackends()).hasSize(1);
}

Performance and Scalability

Performance Considerations

• Memory Usage: Monitor memory consumption of new features
• Execution Time: Profile performance impact on existing operations
• Resource Management: Ensure proper cleanup and resource handling

Scalability Testing

• Load Testing: Test new features under load
• Concurrency: Verify thread safety and concurrent access
• Resource Limits: Test behavior under resource constraints

Documentation and Examples

Code Documentation

• Javadoc: Document all public APIs and interfaces
• Implementation Notes: Document design decisions and trade-offs
• Usage Examples: Provide clear examples of how to use new features

User Documentation

• Feature Guides: Document how to use new capabilities
• Migration Guides: Help users adopt new features
• Best Practices: Share recommended usage patterns

Release and Distribution

Version Management

• Backward Compatibility: Ensure new features don't break existing code
• Feature Flags: Consider feature flags for gradual rollout
• Deprecation Policy: Follow QQQ's deprecation timeline

Distribution

• Maven Central: New modules published to Maven Central
• Documentation: Update wiki and user guides
• Migration Support: Help users adopt new features

See Also

• Developer Onboarding - Development setup
• Testing - Testing strategy
• Contribution Guidelines - PR process