Interface CommandBus

Service for registering and executing commands using the command pattern.

The CommandBus is the central hub for the command pattern implementation. It manages command registration, handler lookup, and command execution. Commands are decoupled from their handlers, allowing for flexible middleware chains and cross-cutting concerns like logging, validation, and authorization.

Key responsibilities:

• Register commands with their handlers
• Execute commands through their registered handlers
• Support middleware for command pipeline
• Dispatch command lifecycle events
• Provide command metadata and discovery

Example

// Register and execute a command
const commandBus = platform.get(PlatformServiceName.CommandBus);

if (commandBus.isSupported(SendEmailCommand)) {
    const command = new SendEmailCommand(context, 'Subject', 'Body');
    await commandBus.handle(command);
}

Example

// Register a custom command handler
const commandBus = platform.get(PlatformServiceName.CommandBus);

const handler = {
    handle: async (command: GenerateReportCommand) => {
        console.log('Generating report...');
        return { success: true, reportUrl: '/reports/123.pdf' };
    }
};

commandBus.register(
    GenerateReportCommand,
    handler,
    {
        title: 'Generate Report',
        description: 'Creates a PDF report',
        icon: 'file-pdf'
    }
);

See

• AnyCommand for base command interface
• CommandHandler for handler interface
• CommandMiddleware for middleware implementation