View

In different framework, the concept of view varies from html itself, the template engine, to the adapter of the template engine, or the response itself. In lit, the view is responsible to generate http response (with render method)

Headers

render is not limited to body, HTTP headers is a part of response, too. Thus, you may populate response headers in view class.

class RestfulView extends AbstractView
{
    public function render(array $data = []): ResponseInterface
    {
        $this->getEmptyBody()->write(json_encode($data['body']));
        if (!empty($data['link'])) {
            $headerline = implode(', ', array_map(function($link){
                return sprintf('<%s; rel="%s">', $link['url'], $link['rel'])
            }, $data['link']));
            $this->response = $this->response
                ->withHeader('Link', $headerline);
        }

        return $this->response
            ->withHeader('Content-Type', 'application/json');
    }
}

Pass values

render accept an array of data, but sometime you might want have type hint, signature, or code completion for some kind of data or metadata, or dependency. We recommend you pass these data by either constructor parameter, or dedicated setter function.

class PlateView extends AbstractView
{
    protected $plate;
    protected $templateName;

    public function __construct(League\Plates\Engine $plate)
    {
        $this->plate = plate;
    }
    
    public function setTemplateName(string $name): self
    {
        $this->templateName = $name;
        return $this;
    }
    
    public function render(array $data = []): ResponseInterface
    {
        $this->getEmptyBody()->write($this->plate->render($this->templateName, $data));
        
        return $this->response;
    }
}

Creating response

ViewInterface requires a setResponse method. Implementation (see ViewTrait) should receive the response instance and use it as the response prototype in render method. By this way, view leaves constructor to have no any requirement, and no need to care about the response / responseFactory.