JsonStrategy.php 3.43 KB
Newer Older
Ketan's avatar
Ketan committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140
<?php
/**
 * Zend Framework (http://framework.zend.com/)
 *
 * @link      http://github.com/zendframework/zf2 for the canonical source repository
 * @copyright Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
 * @license   http://framework.zend.com/license/new-bsd New BSD License
 */

namespace Zend\View\Strategy;

use Zend\EventManager\AbstractListenerAggregate;
use Zend\EventManager\EventManagerInterface;
use Zend\View\Model;
use Zend\View\Renderer\JsonRenderer;
use Zend\View\ViewEvent;

class JsonStrategy extends AbstractListenerAggregate
{
    /**
     * Character set for associated content-type
     *
     * @var string
     */
    protected $charset = 'utf-8';

    /**
     * Multibyte character sets that will trigger a binary content-transfer-encoding
     *
     * @var array
     */
    protected $multibyteCharsets = [
        'UTF-16',
        'UTF-32',
    ];

    /**
     * @var JsonRenderer
     */
    protected $renderer;

    /**
     * Constructor
     *
     * @param  JsonRenderer $renderer
     */
    public function __construct(JsonRenderer $renderer)
    {
        $this->renderer = $renderer;
    }

    /**
     * {@inheritDoc}
     */
    public function attach(EventManagerInterface $events, $priority = 1)
    {
        $this->listeners[] = $events->attach(ViewEvent::EVENT_RENDERER, [$this, 'selectRenderer'], $priority);
        $this->listeners[] = $events->attach(ViewEvent::EVENT_RESPONSE, [$this, 'injectResponse'], $priority);
    }

    /**
     * Set the content-type character set
     *
     * @param  string $charset
     * @return JsonStrategy
     */
    public function setCharset($charset)
    {
        $this->charset = (string) $charset;
        return $this;
    }

    /**
     * Retrieve the current character set
     *
     * @return string
     */
    public function getCharset()
    {
        return $this->charset;
    }

    /**
     * Detect if we should use the JsonRenderer based on model type
     *
     * @param  ViewEvent $e
     * @return null|JsonRenderer
     */
    public function selectRenderer(ViewEvent $e)
    {
        $model = $e->getModel();

        if (! $model instanceof Model\JsonModel) {
            // no JsonModel; do nothing
            return;
        }

        // JsonModel found
        return $this->renderer;
    }

    /**
     * Inject the response with the JSON payload and appropriate Content-Type header
     *
     * @param  ViewEvent $e
     * @return void
     */
    public function injectResponse(ViewEvent $e)
    {
        $renderer = $e->getRenderer();
        if ($renderer !== $this->renderer) {
            // Discovered renderer is not ours; do nothing
            return;
        }

        $result   = $e->getResult();
        if (! is_string($result)) {
            // We don't have a string, and thus, no JSON
            return;
        }

        // Populate response
        $response = $e->getResponse();
        $response->setContent($result);
        $headers = $response->getHeaders();

        if ($this->renderer->hasJsonpCallback()) {
            $contentType = 'application/javascript';
        } else {
            $contentType = 'application/json';
        }

        $contentType .= '; charset=' . $this->charset;
        $headers->addHeaderLine('content-type', $contentType);

        if (in_array(strtoupper($this->charset), $this->multibyteCharsets)) {
            $headers->addHeaderLine('content-transfer-encoding', 'BINARY');
        }
    }
}