Simple YouTube API Crawler class for Wordpress

youtube-crawler.php

<?php

use Illuminate\Support\Arr;
use Illuminate\Support\Str;
use Illuminate\Database\Capsule\Manager as Capsule;

/**
 * Simple YouTube Crawler class for Worpress
 *
 * @author Mike van Veenhuijzen <mikevv@gmail.com>
 *
 **/ 

class YoutubeCrawler {

    const MAX_RESULTS = 50;

    const VIDEO_STATUS_SUCCESS = 'success';
    const VIDEO_STATUS_FAILED = 'failure';
    const VIDEO_STATUS_SKIPPED = 'skipped';

    /**
     * YouTube API 
     * @var Google_Service_YouTube $api 
     */
    protected $api = null;

    /**
     * Write to log
     * @var bool $log 
     **/
    protected $log = true;
    
    /**
     * YouTube API items criteria
     * @var $title_match array 
     **/
    protected $criteria = array(
        'playlistItem' => array(
            'snippet.title' => array(
                'compare' => 'contains',
                'value' => array('VR', 'Virtual reality', '360')
            ),
            'status.embeddable' => array(
                'compare' => '=',
                'value' => true
            ),
            'status.privacyStatus' => array(
                'compare' => '=',
                'value' => 'public'
            )
        ),
        'video' => array(
            'statistics.viewCount' => array(
                'compare' => '>=',
                'value' => 500
            )
        ),
        'channel' => array(
            'contentDetails.relatedPlaylists' => array(
                'compare' => 'has',
                'value' => array('uploads')
            )
        )
    );

    /**
     * Initialize class
     **/
    public function __construct()
    {
        $this->setup();
    }

    /**
     * Execute crawler functionality
     * @return array
     **/
    public function run()
    {
        // Get least updated channel
        $channel = Channel::orderBy('updated_at', 'ASC')->first();

        // Fail if none found
        if ($channel === null) {
            throw new Exeception('No channel found');
        }

        // Get playlist ID if it's missing
        if (empty($channel->playlist_id)) {
            $channel->playlist_id = $this->youtube_playlist_id($channel->url, 'uploads');
            $channel->timestamps = false;
            $channel->save();
        }

        // Fail if still nothing found
        if (empty($channel->playlist_id)) {
            throw new Exeception('No playlist found');
        }

        // Get playlist items
        $videos = $this->youtube_playlist_items(array(
            'playlistId' => $channel->playlist_id
        ));

        // Update video items with supplemented parts
        if (! empty($videos)) {
            $videos = $this->supplement($videos, array('statistics'));
        }

        // Save videos
        $statistics = $this->save($videos);

        // Log statistics
        $this->log(strtr('Latest API call resulted in %total% videos from which %success% were saved, %skipped% were skipped and %failed% failed.', array(
            '%total%'       => count($videos),
            '%success%'     => count(array_keys($statistics, self::VIDEO_STATUS_SUCCESS, true)),
            '%failed%'      => count(array_keys($statistics, self::VIDEO_STATUS_FAILED, true)),
            '%skipped%'     => count(array_keys($statistics, self::VIDEO_STATUS_SKIPPED, true)),
        )));

        // Update channel statistics
        $channel->timestamps = true;
        $channel->increment('video_count', count($videos)); // Estimation because we save API returned video count (and not Wordpress posts)
        $channel->touch();
        $channel->save();

        return true;
    }

    /**
     * Write log to file
     * @param mixed $data
     * @return bool
     */
    public function log($data)
    {
        if (! $this->log) {
            return null;
        }
        $time = date('Y-m-d H:i:s');
        $message = is_string($data) ? $data : print_r($data, true);
        return file_put_contents(YTC_PLUGIN_DIR . 'log.txt', sprintf('[%s] %s', $time, $message) . PHP_EOL, FILE_APPEND) !== false;
    }

    /**
     * Supplement videos with extra parts
     * @param array $videos
     * @param array $parts
     * @param array
     **/
    protected function supplement($videos, $parts)
    {
        // Remove already present videos form API call
        $videos_filtered = array_filter($videos, function($video) {
            return ! $this->video_exists($video);
        });

        // Return original array if supplementing is unneeded
        if (empty($videos_filtered)) {
            return $videos;
        }

        // Collect video IDs
        $video_ids = array_map(function($video) {
            return $video->snippet->resourceId->videoId;
        }, $videos_filtered);

        // Get videos with supplemented parts
        $videos_with_supplemented_data = $this->youtube_videos(array(
            'part' => implode(',', $parts),
            'id' => implode(',', $video_ids)
        ));

        return array_merge_recursive($videos, $videos_with_supplemented_data);
    }

    /**
     * YouTube videos API call
     * @link https://developers.google.com/youtube/v3/docs/videos/list
     * @param array $parameters
     * @return array Video collection matching search criteria
     **/
    protected function youtube_videos(array $parameters)
    {

        $defaults = array(
            'maxResults' => self::MAX_RESULTS,
            'userIp' => $_SERVER['REMOTE_ADDR']
        );

        $parameters = array_merge($defaults, $parameters);

        $this->log('Fire API call: ' . http_build_query($parameters));

        $response = $this->api->videos->listVideos(null, $parameters);

        return $this->parse_response($response);
    }

    /**
     * YouTube PlaylistItems API call
     * @link https://developers.google.com/youtube/v3/docs/playlistItems/list
     * @param array $parameters
     * @return array Video collection matching search criteria
     **/
    protected function youtube_playlist_items(array $parameters)
    {

        if ( ! isset($parameters['playlistId'])) {
            throw new Exeception('Required playlistId parameter is missing');
        }

        $parts = array(
            'id',
            'snippet',
            'status'
        );

        $defaults = array(
            'part' => implode(',', $parts),
            'maxResults' => self::MAX_RESULTS,
            'userIp' => $_SERVER['REMOTE_ADDR']
        );

        $parameters = array_merge($defaults, $parameters);

        $this->log('Fire API call: ' . http_build_query($parameters));

        $response = $this->api->playlistItems->listPlaylistItems(null, $parameters);

        return $this->parse_response($response);
    }

    /**
     * YouTube Search API call
     * @link https://developers.google.com/youtube/v3/docs/search/list
     * @param array $parameters
     * @return array Video collection matching search criteria
     **/
    protected function youtube_search(array $parameters)
    {
        if ( ! isset($parameters['channelId'])) {
            //throw new Exeception('Required channelId parameter is missing');
        }

        $parts = array(
            'id',
            'snippet',
        );

        $defaults = array(
            'part' => implode(',', $parts),
            'maxResults' => self::MAX_RESULTS,
            'safeSearch' => 'none',
            'order' => 'date',
            'type' => 'video',
            'videoEmbeddable' => 'true',
            'videoSyndicated' => 'true',
            'userIp' => $_SERVER['REMOTE_ADDR']
        );

        $parameters = array_merge($defaults, $parameters);

        $this->log('Fire API call: ' . http_build_query($parameters));

        $response = $this->api->search->listSearch(null, $parameters);

        return $this->parse_response($response);

    }

    /**
     * Get Youtube channel ID fomr URL
     * @param string $url
     * @param string $playlist uploads, favorites, likes etc.
     * @return string|null
     **/
    public function youtube_playlist_id($url, $playlist)
    {
        $parameters = array();

        //@todo use regex
        if (strpos($url, 'youtube.com/user/') !== false) {
            $username = explode('youtube.com/user/', $url)[1];
            $parameters['forUsername'] = trim($username);
            $this->log("Try to get playlist_id for {$username} with playlist {$playlist}");
        }

        if (empty($parameters)) {
            return null;
        }

        $response = $this->api->channels->listChannels('contentDetails', $parameters);
        $items = $this->parse_response($response);

        return Arr::get($items, '0.contentDetails.relatedPlaylists.' . $playlist);
    }

    /**
     * Parse Youtube API response
     * @param Google_Collection $response
     * @return array
     **/
    protected function parse_response(Google_Collection $response)
    {
        //@todo capture errors defined in https://developers.google.com/youtube/v3/docs/errors

        $items = array();

        foreach ($response->items as $item) {
            $kind = str_replace('youtube#', '', $item->getKind());
            $model = (array) $item->toSimpleObject();
            $tests = array();
            $results = array();
            $passes = 0;

            // Override tests
            if (isset($this->criteria[$kind])) {
                $tests = $this->criteria[$kind];
            }

            // When no criteria if found for resource. It passes successfully
            if (empty($tests)) {
                $results[] = "{$key} PASSED the test because {$kind} doesn't have any criteria";
            }

            // Loop through required criteria and count passes
            foreach ($tests as $key => $condition) {
                $value = Arr::get($model, $key);
                if (is_null($value)) {
                    $results[] = "{$key} PASSED the '{$condition['compare']}' test because a value was missing or incomplete";
                    $passes++;
                } else if($this->test($condition, $value, $item)) {
                    $results[] = "{$key} PASSED the '{$condition['compare']}' test with value --> {$value}";
                    $passes++;
                } else {
                    $results[] = "{$key} FAILED the '{$condition['compare']}' test with value --> {$value}";
                }
            }

            // Append to array if all passed successfully
            if ($passes === count($tests)) {
                $items[] = $item;
                $this->log('A MATCH is found with the following passes ' . print_r($results, true));
            }

        }

        return $items;
    }

    /**
     * Execute critrium on $value
     * @param array $condition
     * @param mixed $value
     * @param Google_Model $model
     * @return bool
     **/
    protected function test($condition, $value, Google_Model $model = null)
    {
        if (! isset($condition['compare'])) {
            throw new Exeception('Condition compare value is required');
        }

        if (! isset($condition['value'])) {
            throw new Exeception('Condition value is required for comparison');
        }

        // Detection settings
        $strict = isset($condition['strict']) ? $condition['strict'] : false;
        $inverse = isset($condition['inverse']) ? $condition['inverse'] : false;

        // Execute test
        switch(strtolower($condition['compare'])) {
            case '>=' :
                $result = $value >= $condition['value'];
                break;
            case '>' :
                $result = $value > $condition['value'];
                break;
            case '<=' :
                $result = $value <= $condition['value'];
                break;
            case '<' :
                $result = $value < $condition['value'];
                break;
            case '<>' :
            case '!=' :
                $result = $strict ? ($value !== $condition['value']) : ($value != $condition['value']);
                break;
            case '=' :
            case '==' :
                $result = $strict ? ($value === $condition['value']) : ($value == $condition['value']);
                break;
            case 'between' :
                list($minimum, $maximum) = $condition['value'];
                $result = ($value >= $minimum && $value <= $maximum);
                break;
            case 'in' :
                $result = in_array($value, $condition['value'], $strict);
                break;
            case 'has' :
                $result = Arr::has($value, $condition['value']);
                break;
            case 'startswith' :
                $result = Str::startsWith($value, $condition['value']);
                break;
            case 'endswith' :
                $result = Str::endsWith($value, $condition['value']);
                break;
            case 'is' :
            case 'regex' :
                $result = Str::is($condition['value'], $value);
                break;
            case 'contains' :
                if (!$strict) {
                    // Case-insensitive string matching
                    $value = strtolower($value);
                    $values = array_map('strtolower', (array) $condition['value']);
                    $condition['value'] = is_string($condition['value']) ? $values[0] : $values;
                }
                if (empty($condition['value'])) {
                    $result = true;
                    break;
                }
                $result = Str::contains($value, $condition['value']);
                break;
            default:
                throw new Exception('Unknown condition compare value'); 
        }

        return $inverse ? !$result : $result;
    }

    /**
     * Save video as Wordpress post
     * @param array|object $video
     * @return string
     **/
    public function save($video)
    {
        // Walk through collection if it's an array
        if (is_array($video)) {
            return array_map(array($this, 'save'), $video);
        }

        // Skip already existing videos
        if ($this->video_exists($video)) {
            return self::VIDEO_STATUS_SKIPPED;
        }

        // Define post and meta data
        $post = array();
        $meta = array();

        // Default post data
        $post['post_title'] = $video->id;
        $post['post_type'] = 'post';
        $post['post_status'] = 'draft';

        // Default meta data
        $meta['ytc_video_id'] = $video->id;

        // Extend with video snippet data
        if (isset($video->snippet)) {
            $post['post_title'] = $video->snippet->title;
            $post['post_name'] = sanitize_title($video->snippet->title);
            $post['post_content'] = $video->snippet->description;
            $post['post_content'] .= "\n\nhttps://www.youtube.com/watch?v=" . $video->snippet->resourceId->videoId; // Append YouTube video URL
            //$post['post_date'] => $video->snippet->publishedAt;

            $meta['ytc_video_id'] = $video->snippet->resourceId->videoId;
            $meta['ytc_published_at'] = $video->snippet->publishedAt;
            $meta['ytc_channel_id'] = $video->snippet->channelId;
            $meta['ytc_channel_title'] = $video->snippet->channelTitle;
        }

        // Extend with video statistics data
        if (isset($video->statistics)) {
            $meta['ytc_view_count'] = $video->statistics->viewCount;
            $meta['ytc_like_count'] = $video->statistics->likeCount;
        }

        // Save post
        $post_id = wp_insert_post($post);

        // Failed because of unknown reason
        if (empty($post_id)) {
            return self::VIDEO_STATUS_FAILED;
        }

        // Save meta data
        foreach ($meta as $key => $value) {
            if (! is_null($value)) {
                update_post_meta($post_id, $key, $value);
            }   
        }

        return self::VIDEO_STATUS_SUCCESS;
    }

    /**
     * Check if video already exists in database
     * @param Google_Model $video
     * @return bool
     **/
    public function video_exists(Google_Model $video)
    {
        // Or check video ID presence in post description??
        //$post_query = Capsule::table('posts')->where('post_content', 'like', '%' . $video->id . '%');

        $postmeta_query = Capsule::table('postmeta')->where(array(
            'meta_key' => 'ytc_video_id',
            'meta_value' => $video->id
        ));

        if (isset($video->snippet)) {
            $postmeta_query->orWhere(array(
                'meta_key' => 'ytc_video_id',
                'meta_value' => $video->snippet->resourceId->videoId
            ));
        }

        return $postmeta_query->exists();
    }

    /**
     * Setup requirements such as database and API connection
     * @global $wpdb
     * @return void
     */
    public function setup()
    {
        global $wpdb;

        // Database settings
        $db = array(
            'driver'    => 'mysql',
            'host'      => DB_HOST,
            'database'  => DB_NAME,
            'username'  => DB_USER,
            'password'  => DB_PASSWORD,
            'charset'   => 'utf8',
            'collation' => 'utf8_general_ci',
            'prefix'    => $wpdb->prefix,
        );

        // Fix for port within hostname
        if (strpos($db['host'], ':') !== false) {
            list($host, $port) = explode(':', $db['host']);
            $db['host'] = $host;
            $db['port'] = $port;
        }

        // Set timezone same as Wordpress
        date_default_timezone_set(get_option('timezone_string', 'UTC'));

        // Connect to database
        $capsule = new Capsule;
        $capsule->addConnection($db);
        $capsule->setAsGlobal();
        $capsule->bootEloquent();

        // Setup YouTube API
        if (! defined('YOUTUBE_API_KEY')) {
            throw new Exception('YOUTUBE_API_KEY should be defined within wp-config.php or somewhere else');
        }

        $client = new Google_Client();
        $client->setDeveloperKey(YOUTUBE_API_KEY);

        // Circumvent SSL errors (non-secure but works)
        if (empty($_SERVER['HTTPS']) || $_SERVER['HTTPS'] === 'off') {
            $httpClient = new GuzzleHttp\Client([
                'verify' => false, // otherwise HTTPS requests will fail.
            ]);
            $client->setHttpClient($httpClient);
        }

        $this->api = new Google_Service_YouTube($client);

    }
    
    /**
     * Plugin activation procedure
     * @return void
     **/
    public static function plugin_activation()
    {
        Channel::initialize();
    }

    /**
     * Plugin deactivation procedure
     * @return void
     **/
    public static function plugin_deactivation()
    {
        //nothing needed here.
    }
}

?>

I just pasted this here to hopefully inspire others to continue this work :)
This class has more dependencies then are pasted in this gist. If somebody is interested in it, please let me know.