Yii2 Tactician Command Bus

This is a Yii Framework 2 Wrapper/Adapter for Tactician Command Bus Library. It provides an easy way to use the command bus pattern in Yii2 Based apps.

When should I use Command Bus?

Tactician is a great fit if you’ve got a service layer. If you’re not sure what a service layer is, Martin Fowler’s PoEAA is a good starting point. Tactician’s author also did a talk on the subject.

Commands really help capture user intent. They’re also a great stand-in for the models when it comes to forms or serializer libraries that expect getter/setter objects.

The command bus itself is really easy to decorate with extra behaviors, like locking or database transactions so it’s very easy to extend with plugins.

By: tactician.thephpleague.com

When should I NOT use it?

If you’ve got a very small app that doesn’t need a service layer, then Tactician won’t offer much to you.

If you’re already using a tool that provides a command bus (like Broadway), you’re probably okay there too.

By: tactician.thephpleague.com

Installation

$ composer require dersonsena/yii2-tactician

Setup

First you must have configure your Yii Dependency Injection Container to be able to use Command and Handler classes within it.

You should have something like this in your config/web.php:

$config = [
    'id' => 'your-app-id',
    //...
    'container' => [
        'definitions' => [
            MyClassCommand::class => MyClassHandler::class 
        ]
    ],
    'components' => [
        //...
    ]
];

IMPORTANT: you must follow the conventions below:

• Your Command class must be suffixed by Command;
• Your Handler class must be: Same Command Class Name + Without Command Suffix + Handler.

The last one is register Yii2TacticianCommandBus component in your config/web.php file, as below:

$config = [
    'id' => 'your-app-id',
    //...
    'container' => [
        'definitions' => [
            MyClassCommand::class => MyClassHandler::class 
        ]
    ],
    'components' => [
        'commandBus' => [
            'class' => DersonSena\Yii2Tactician\Yii2TacticianCommandBus::class
        ],
        // other components...
    ]
];

How to Use

Mapping Command and Handler Classes

Define a Command class somewhere in your application, for example:

class MyClassCommand
{
    public $someParam;
    public $someOtherParam;

    public function __construct($someParam, $someOtherParam = 'defaultValue')
    {
    	$this->someParam = $someParam;
        $this->someOtherParam = $someOtherParam;
    }
}

Define your Handler class should be something like:

class MyClassHandler
{
    public function handle(MyClassCommand $command)
    {
    	// do command stuff here!
        // we can use $command->someParam and $this->someOtherParam
    }
}

Now we can use this command in controllers or wherever you want:

public function actionDoSomething()
{
    $queryParam = Yii::$app->getRequest()->get('some_param');
    
    // Here the magic happens! =)
    $result = Yii::$app->commandBus->handle(new MyClassCommand($queryParam));

    if ($result === true) {
    	return $this->redirect(['go/to/some/place']);
    }

    return $this->render('some-awesome-view');
}

Using String Path

You can use a command class as String Path instead of concrete object. For this case, just do:

$config = [
    'id' => 'your-app-id',
    //...
    'container' => [
        'definitions' => [
            // you can use any string here.
            'awesome.alias.to.be.called.anywhere' => MyClassHandler::class 
        ]
    ],
    'components' => [
        //...
    ]
];

Your Handle Class should be as follows:

class MyClassHandler implements \DersonSena\Yii2Tactician\Handler
{
    public function handle(MyClassCommand $command)
    {
    	// do command stuff here!
        // we can use $command->someParam and $this->someOtherParam
    }
    
    public function commandClassName(): string
    {
        return MyClassCommand::class;
    }
}

IMPORTANT: in this way your Handler Class MUST implements the DersonSena\Yii2Tactician\Handler interface and your Command Class MUST implements DersonSena\Yii2Tactician\Command.

Your controller action or anywhere else:

public function actionDoSomething()
{
    $result = Yii::$app->commandBus->handle('awesome.alias.to.be.called.anywhere', [
        'someParam' => 'abc',
        'someOtherParam' => 'def'
    ]);
    
    // .. other logics
}

Under the hood the Command Bus System will call:

MyClassHandler::handle($command);

where $command argument is created inside that like:

MyClassCommand::create([someParam' => 'abc', 'someOtherParam' => 'def']);

Enjoy =).

Authors

• Kilderson Sena - Owner - Yii Academy

See also the list of contributors who participated in this project.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

Licence

This package is released under the MIT License. See the bundled LICENSE for details.

References

• thephpleague/tactician
• pavelmics/YiiTactician