Sample MIK metadata manipulator

gistfile1.txt

<?php

namespace mik\metadatamanipulators;
use \Monolog\Logger;

/**
 * MJTest - Example metadata manipulator. 
 *
 * The mappings file must contain a row that adds the following
 * element to your MODS:
 * nullN,<extension><foo></foo></extension>.
 *
 * If the value of the current object's Caroonist metadata property
 * is 'Krieger, Bob', add the element.
 *
 * This metadata manipulator takes no configuration parameters.
 */
class MJTest extends MetadataManipulator
{
    /**
     * Create a new metadata manipulator Instance.
     */
    public function __construct($settings = null, $paramsArray, $record_key)
    {
        parent::__construct($settings, $paramsArray, $record_key);
        $this->record_key = $record_key;
        // Set up logger.
        $this->pathToLog = $this->settings['LOGGING']['path_to_manipulator_log'];
        $this->log = new \Monolog\Logger('config');
        $this->logStreamHandler = new \Monolog\Handler\StreamHandler($this->pathToLog,
            Logger::INFO);
        $this->log->pushHandler($this->logStreamHandler);
    }

    /**
     * General manipulate wrapper method.
     *
     *  @param string $input The XML fragment to be manipulated. We are only
     *     interested in the <extension><foo> fragment added in the
     *     MIK mappings file.
     *
     * @return string
     *     One of the manipulated XML fragment, the original input XML if the
     *     input is not the fragment we are interested in, or an empty string
     *     if we don't want to add the fragment to our MODS.xml.
     */
    public function manipulate($input)
    {
        $dom = new \DomDocument();
        $dom->loadxml($input, LIBXML_NSCLEAN);

        // Test to see if the current fragment is <extension><foo>.
        $xpath = new \DOMXPath($dom);
        $foos = $xpath->query("//extension/foo");
        if ($foos->length === 1) {
            $foo = $foos->item(0);
            // Get the raw metadata (in the CSV toolchain, it will be a serialized object) so
            // we can make decisions based on any value in it.
            $raw_metadata_cache_path = $this->settings['FETCHER']['temp_directory'] . DIRECTORY_SEPARATOR .
                $this->record_key . '.metadata';
            $raw_metadata_cache = file_get_contents($raw_metadata_cache_path);
            $metadata = unserialize($raw_metadata_cache);
            // In this example, we want to know if this is a Krieger cartoon.
            if ($metadata->Cartoonist == 'Krieger, Bob') {
                // If it is, add our snippet.
                $foo->nodeValue = "This cartoon is by Bob Krieger.";
                return $dom->saveXML($dom->documentElement);
            }
            else {
                return '';
            }
        }
        else {
            // If current fragment is not <extension><foo>, just return it.
            return $input;
        }
    }
}