Bus

The bus dispatches commands to their respective handlers. The interface exposes the following methods, execute, resolveHandler and handlersNamespace.

execute(...)

Expects CommandInterface $command. Its job is to resolve the handler for this command, execute it and return the result of the operation.

return $this
    ->resolveHandler($command->serial())
    ->execute($command);

resolveHandler(...)

Expects a command $serial. Its job is to resolve the handler for the given command and return it.

$class = $this->getClassNameFromSerial($serial);
if (class_exists($class)) {
    return new $class();
}

throw new NoSupportedHandlerFoundException($serial);

handlersNamespace()

Returns the namespace where the command handlers are located.

return 'App\Lib\Commands\Handlers';

Command

A command is simply a container for data that will be used by its handler to perform a given task, the interface exposes one method serial

example container

public $digit;

public function __construct($digit)
{
    $this->digit = $digit;
}

// Initialized as $command = new GetDigitPlusOneCommand(7);

serial()

The serial should return a snake_case string that uniquely identifies this command.

return 'get_digit_plus_one';

Handler

The handlers job is to take a command, optionally extract its data and perform a task on it. It will then return the result back to the Bus. The interface exposes one method execute.

execute(...)

Expects a CommandInterface $command and returns the result of an operation.

$digit = $command->digit;
return (int) $digit + 1;