lean/src/Response/FileDownloadResponse.php

<?php declare(strict_types=1);

namespace Lean\Response;

use function get_class, gettype, is_object, is_string, sprintfm, pathinfo, PATHINFO_EXTENSION;

use Psr\Http\Message\StreamInterface;

use Laminas\Diactoros\Exception,
    Laminas\Diactoros\Response,
    Laminas\Diactoros\Stream,
    Laminas\Diactoros\Response\InjectContentTypeTrait;

/**
 * PDF Response
 *
 * Allows creating a response by passing a string to the constructor;
 * by default, sets a status code of 200 and sets the Content-Type header to
 * application/pdf.
 */
class FileDownloadResponse extends Response
{
    use InjectContentTypeTrait;

    /**
     * Create a PDF response
     *
     * Produces a pdf response with a Content-Type of application/json and a default
     * status of 200.
     *
     * @param string|StreamInterface $filepath String or stream for the message body.
     * @param int $status Integer status code for the response; 200 by default.
     * @param array $headers Array of headers to use at initialization.
     * @throws Exception\InvalidArgumentException if $filepath is neither a string or stream.
     */
    public function __construct($filepath, int $status = 200, array $headers = [])
    {
        $body = $this->createBody($filepath);

        if (class_exists(\Mimey\MimeTypes::class)) {
            $mime = (new \Mimey\MimeTypes())->getMimeType(pathinfo($filepath, PATHINFO_EXTENSION));
        }
        else {
            $finfo = finfo_open(FILEINFO_MIME_TYPE);
            $mime = finfo_file($finfo, $filepath);
            finfo_close($finfo);
        }

        parent::__construct(
            $body,
            $status,
            $this->injectContentType($mime, $headers)
        );
    }

    /**
     * Create the message body.
     *
     * @param string|StreamInterface $filepath
     * @throws Exception\InvalidArgumentException if $filepath is neither a string or stream.
     */
    private function createBody($filepath) : StreamInterface
    {
        if ($filepath instanceof StreamInterface) {
            return $filepath;
        }

        if (! is_string($filepath)) {
            throw new Exception\InvalidArgumentException(sprintf(
                'Invalid content (%s) provided to %s',
                (is_object($filepath) ? get_class($filepath) : gettype($filepath)),
                __CLASS__
            ));
        }
        
        if ( ! file_exists($filepath) ) {
            throw new Exception\InvalidArgumentException("Given file (%s) do not look like a valid file path.", $filepath);
        }

        if ( ! is_readable($filepath) ) {
            throw new Exception\InvalidArgumentException("Given file (%s) do not seem to be readable. This could indicate a permission problem", $filepath);
        }
        
        return new Stream(fopen($filepath, "r"), 'r');
    }
}