How to use external PHP library in Joomla! CLI application - Class not found

Question

I'm working on a custom Joomla! CLI application and would like to rely on an external PHP library to reuse some functionality.

// Set flag that this is a parent file.
const _JEXEC = 1;

error_reporting(E_ALL | E_NOTICE);
//error_reporting(E_ALL & ~E_NOTICE);
ini_set('display_errors', 1);

// Load system defines
if (file_exists(dirname(__DIR__) . '/defines.php'))
{
    require_once dirname(__DIR__) . '/defines.php';
}

if (!defined('_JDEFINES'))
{
    define('JPATH_BASE', dirname(__DIR__));
    require_once JPATH_BASE . '/includes/defines.php';
}

require_once JPATH_LIBRARIES . '/import.legacy.php';
require_once JPATH_LIBRARIES . '/cms.php';

// Load the configuration
require_once JPATH_CONFIGURATION . '/configuration.php';

require_once JPATH_SITE . '/modules/gng/gng_shared.php';

$myApp = JApplicationCli::getInstance('GNGEmailToGuideDownloader');
$hostname = GNGParam::getParam('email', 'hostname');
$username = GNGParam::getParam('email_account_guides', 'username');
$password = GNGParam::getParam('email_account_guides', 'password');
$myApp->initStream($hostname, $username, $password);
$myApp->execute();

The CLI application is based on the GNGEmailToGuideDownloader class that is stored in the gng_shared.php file. This class should use the functionalities of the external library.

I copied the directory structure of the source code of the library in the same folder where the gng_shared.php file is stored:

Finally I tried to use the JLoader::register mechanism to load the classes in the library, so that I can instantiate and use them:

//retrieves new guides@ email from the server, saves it in the DB and notifies the guide
class GNGEmailToGuideDownloader extends GNGEmailDownloader  
{
    //downloads the emails from the stream and assigns them to a tour or inquiry
    public function loadEmails() {

        $filepath = JPATH_SITE . '/modules/gng/EmailReplyParser/Parser/EmailParser.php';
        if (file_exists($filepath)) {
            JLoader::register('EmailParser', $filepath);
            $parser = new EmailParser();
        } 

In the EmailParser.php there is the appropriate class:

namespace EmailReplyParser\Parser;

use EmailReplyParser\Email;
use EmailReplyParser\Fragment;

/**
 * @author William Durand <[email protected]>
 */
class EmailParser
{
    const QUOTE_REGEX = '/>+$/s';

However on the line where I'm trying to create the parser object I get the following error message when I'm running the CLI app:

Fatal error: Class 'EmailParser' not found in /home/gonative/public_html/dev/modules/gng/gng_shared.php on line 1737

What am I doing wrong?

Answer 1

Use JLoader::registerNamespace() to register this library's namespace. This should work for you current folder structure:

JLoader::registerNamespace('EmailReplyParser\\Parser', __DIR__, false, false, 'psr0');

Or you can use the included autoloader:

require_once __DIR__ . '/autoload.php';

Then add import statements before using the classes:

use EmailReplyParser\Parser\EmailParser;

$parser = new EmailParser;

Or use full classnames:

$parser = new EmailReplyParser\Parser\EmailParser;