Wordpress Export: Parse the WP exported xml file

WpParser.php

<?php

namespace App\Helpers\Import;

/**
 * WordPress exported XML Parser class for managing parsing of XML files.
 * This class is cloned from the link below with partially modified.
 * https://github.com/wecodemore/wp-importer
 */
class WpParser
{
    function parse($file)
    {
        try {
            // Attempt to use proper XML parsers first
            if (extension_loaded('simplexml')) {
                $result = $this->simpleXMLparser($file);
                return $result;
            } else if (extension_loaded('xml')) {
                $parser = new XMLParser;
                $result = $parser->parse($file);
                return $result;
            }

            // use regular expressions if nothing else available or this is bad XML
            $parser = new RegexParser;
            return $parser->parse($file);
        } catch (\Exception $e) {
            return null;
        }
    }

    function simpleXMLparser($file)
    {
        $authors = $posts = $categories = $tags = $terms = array();


        $dom = new \DOMDocument;
        $success = $dom->loadXML(file_get_contents($file));
        if (!$success || isset($dom->doctype)) {
            return new \Exception('SimpleXML_parse_error: ' .  libxml_get_errors());
        }

        $xml = simplexml_import_dom($dom);
        unset($dom);

        // halt if loading produces an error
        if (!$xml)
            return new \Exception('SimpleXML_parse_error: ' .  libxml_get_errors());

        $wxr_version = $xml->xpath('/rss/channel/wp:wxr_version');
        if (!$wxr_version)
            return new \Exception('WXR_parse_error');

        $wxr_version = (string) trim($wxr_version[0]);
        // confirm that we are dealing with the correct file format
        if (!preg_match('/^\d+\.\d+$/', $wxr_version))
            return new \Exception('WXR_parse_error ' . $wxr_version);

        $base_url = $xml->xpath('/rss/channel/wp:base_site_url');
        $base_url = (string) trim($base_url[0]);

        $namespaces = $xml->getDocNamespaces();
        if (!isset($namespaces['wp']))
        $namespaces['wp'] = 'http://wordpress.org/export/1.1/';
        if (!isset($namespaces['excerpt']))
        $namespaces['excerpt'] = 'http://wordpress.org/export/1.1/excerpt/';

        // grab authors
        foreach ($xml->xpath('/rss/channel/wp:author') as $author_arr) {
            $a = $author_arr->children($namespaces['wp']);
            $login = (string) $a->author_login;
            $authors[$login] = array(
                'author_id' => (int) $a->author_id,
                'author_login' => $login,
                'author_email' => (string) $a->author_email,
                'author_display_name' => (string) $a->author_display_name,
                'author_first_name' => (string) $a->author_first_name,
                'author_last_name' => (string) $a->author_last_name
            );
        }

        // grab cats, tags and terms
        foreach ($xml->xpath('/rss/channel/wp:category') as $term_arr) {
            $t = $term_arr->children($namespaces['wp']);
            $categories[] = array(
                'term_id' => (int) $t->term_id,
                'category_nicename' => (string) $t->category_nicename,
                'category_parent' => (string) $t->category_parent,
                'cat_name' => (string) $t->cat_name,
                'category_description' => (string) $t->category_description
            );
        }

        foreach ($xml->xpath('/rss/channel/wp:tag') as $term_arr) {
            $t = $term_arr->children($namespaces['wp']);
            $tags[] = array(
                'term_id' => (int) $t->term_id,
                'tag_slug' => (string) $t->tag_slug,
                'tag_name' => (string) $t->tag_name,
                'tag_description' => (string) $t->tag_description
            );
        }

        foreach ($xml->xpath('/rss/channel/wp:term') as $term_arr) {
            $t = $term_arr->children($namespaces['wp']);
            $terms[] = array(
                'term_id' => (int) $t->term_id,
                'term_taxonomy' => (string) $t->term_taxonomy,
                'slug' => (string) $t->term_slug,
                'term_parent' => (string) $t->term_parent,
                'term_name' => (string) $t->term_name,
                'term_description' => (string) $t->term_description
            );
        }

        // grab posts
        foreach ($xml->channel->item as $item) {
            $post = array(
                'post_title' => (string) $item->title,
                'guid' => (string) $item->guid,
            );

            $dc = $item->children('http://purl.org/dc/elements/1.1/');
            $post['post_author'] = (string) $dc->creator;

            $content = $item->children('http://purl.org/rss/1.0/modules/content/');
            $excerpt = $item->children($namespaces['excerpt']);
            $post['post_content'] = (string) $content->encoded;
            $post['post_excerpt'] = (string) $excerpt->encoded;

            $wp = $item->children($namespaces['wp']);
            $post['post_id'] = (int) $wp->post_id;
            $post['post_date'] = (string) $wp->post_date;
            $post['post_date_gmt'] = (string) $wp->post_date_gmt;
            $post['comment_status'] = (string) $wp->comment_status;
            $post['ping_status'] = (string) $wp->ping_status;
            $post['post_name'] = (string) $wp->post_name;
            $post['status'] = (string) $wp->status;
            $post['post_parent'] = (int) $wp->post_parent;
            $post['menu_order'] = (int) $wp->menu_order;
            $post['post_type'] = (string) $wp->post_type;
            $post['post_password'] = (string) $wp->post_password;
            $post['is_sticky'] = (int) $wp->is_sticky;

            if (isset($wp->attachment_url))
                $post['attachment_url'] = (string) $wp->attachment_url;

            foreach ($item->category as $c) {
                $att = $c->attributes();
                if (isset($att['nicename']))
                $post['terms'][] = array(
                    'name' => (string) $c,
                    'slug' => (string) $att['nicename'],
                    'domain' => (string) $att['domain']
                );
            }

            foreach ($wp->postmeta as $meta) {
                $post['postmeta'][] = array(
                    'key' => (string) $meta->meta_key,
                    'value' => (string) $meta->meta_value
                );
            }

            foreach ($wp->comment as $comment) {
                $meta = array();
                if (isset($comment->commentmeta)) {
                    foreach ($comment->commentmeta as $m) {
                        $meta[] = array(
                            'key' => (string) $m->meta_key,
                            'value' => (string) $m->meta_value
                        );
                    }
                }

                $post['comments'][] = array(
                    'comment_id' => (int) $comment->comment_id,
                    'comment_author' => (string) $comment->comment_author,
                    'comment_author_email' => (string) $comment->comment_author_email,
                    'comment_author_IP' => (string) $comment->comment_author_IP,
                    'comment_author_url' => (string) $comment->comment_author_url,
                    'comment_date' => (string) $comment->comment_date,
                    'comment_date_gmt' => (string) $comment->comment_date_gmt,
                    'comment_content' => (string) $comment->comment_content,
                    'comment_approved' => (string) $comment->comment_approved,
                    'comment_type' => (string) $comment->comment_type,
                    'comment_parent' => (string) $comment->comment_parent,
                    'comment_user_id' => (int) $comment->comment_user_id,
                    'commentmeta' => $meta,
                );
            }

            $posts[] = $post;
        }

        return array(
            'authors' => $authors,
            'posts' => $posts,
            'categories' => $categories,
            'tags' => $tags,
            'terms' => $terms,
            'base_url' => $base_url,
            'version' => $wxr_version
        );
    }
}


/**
 * Parser that makes use of the XML Parser PHP extension.
 */
class XMLParser
{
    var $wp_tags = array(
        'wp:post_id', 'wp:post_date', 'wp:post_date_gmt', 'wp:comment_status', 'wp:ping_status', 'wp:attachment_url',
        'wp:status', 'wp:post_name', 'wp:post_parent', 'wp:menu_order', 'wp:post_type', 'wp:post_password',
        'wp:is_sticky', 'wp:term_id', 'wp:category_nicename', 'wp:category_parent', 'wp:cat_name', 'wp:category_description',
        'wp:tag_slug', 'wp:tag_name', 'wp:tag_description', 'wp:term_taxonomy', 'wp:term_parent',
        'wp:term_name', 'wp:term_description', 'wp:author_id', 'wp:author_login', 'wp:author_email', 'wp:author_display_name',
        'wp:author_first_name', 'wp:author_last_name',
    );
    var $wp_sub_tags = array(
        'wp:comment_id', 'wp:comment_author', 'wp:comment_author_email', 'wp:comment_author_url',
        'wp:comment_author_IP',    'wp:comment_date', 'wp:comment_date_gmt', 'wp:comment_content',
        'wp:comment_approved', 'wp:comment_type', 'wp:comment_parent', 'wp:comment_user_id',
    );

    function parse($file)
    {
        $this->wxr_version = $this->in_post = $this->cdata = $this->data = $this->sub_data = $this->in_tag = $this->in_sub_tag = false;
        $this->authors = $this->posts = $this->term = $this->category = $this->tag = array();

        $xml = xml_parser_create('UTF-8');
        xml_parser_set_option($xml, XML_OPTION_SKIP_WHITE, 1);
        xml_parser_set_option($xml, XML_OPTION_CASE_FOLDING, 0);
        xml_set_object($xml, $this);
        xml_set_character_data_handler($xml, 'cdata');
        xml_set_element_handler($xml, 'tag_open', 'tag_close');

        if (!xml_parse($xml, file_get_contents($file), true)) {
            $current_line = xml_get_current_line_number($xml);
            $current_column = xml_get_current_column_number($xml);
            $error_code = xml_get_error_code($xml);
            $error_string = xml_error_string($error_code);
            return new \Exception('XML_parse_error: ' . $error_string);
        }
        xml_parser_free($xml);

        if (!preg_match('/^\d+\.\d+$/', $this->wxr_version))
            return new \Exception('WXR_parse_error - invalid version number: ' . $this->wxr_version);

        return array(
            'authors' => $this->authors,
            'posts' => $this->posts,
            'categories' => $this->category,
            'tags' => $this->tag,
            'terms' => $this->term,
            'base_url' => $this->base_url,
            'version' => $this->wxr_version
        );
    }

    function tag_open($parse, $tag, $attr)
    {
        if (in_array($tag, $this->wp_tags)) {
            $this->in_tag = substr($tag, 3);
            return;
        }

        if (in_array($tag, $this->wp_sub_tags)) {
            $this->in_sub_tag = substr($tag, 3);
            return;
        }

        switch ($tag) {
            case 'category':
                if (isset($attr['domain'], $attr['nicename'])) {
                    $this->sub_data['domain'] = $attr['domain'];
                    $this->sub_data['slug'] = $attr['nicename'];
                }
                break;
            case 'item':
                $this->in_post = true;
            case 'title':
                if ($this->in_post) $this->in_tag = 'post_title';
                break;
            case 'guid':
                $this->in_tag = 'guid';
                break;
            case 'dc:creator':
                $this->in_tag = 'post_author';
                break;
            case 'content:encoded':
                $this->in_tag = 'post_content';
                break;
            case 'excerpt:encoded':
                $this->in_tag = 'post_excerpt';
                break;

            case 'wp:term_slug':
                $this->in_tag = 'slug';
                break;
            case 'wp:meta_key':
                $this->in_sub_tag = 'key';
                break;
            case 'wp:meta_value':
                $this->in_sub_tag = 'value';
                break;
        }
    }

    function cdata($parser, $cdata)
    {
        if (!trim($cdata))
            return;

        $this->cdata .= trim($cdata);
    }

    function tag_close($parser, $tag)
    {
        switch ($tag) {
            case 'wp:comment':
                unset($this->sub_data['key'], $this->sub_data['value']); // remove meta sub_data
                if (!empty($this->sub_data))
                    $this->data['comments'][] = $this->sub_data;
                $this->sub_data = false;
                break;
            case 'wp:commentmeta':
                $this->sub_data['commentmeta'][] = array(
                    'key' => $this->sub_data['key'],
                    'value' => $this->sub_data['value']
                );
                break;
            case 'category':
                if (!empty($this->sub_data)) {
                    $this->sub_data['name'] = $this->cdata;
                    $this->data['terms'][] = $this->sub_data;
                }
                $this->sub_data = false;
                break;
            case 'wp:postmeta':
                if (!empty($this->sub_data))
                    $this->data['postmeta'][] = $this->sub_data;
                $this->sub_data = false;
                break;
            case 'item':
                $this->posts[] = $this->data;
                $this->data = false;
                break;
            case 'wp:category':
            case 'wp:tag':
            case 'wp:term':
                $n = substr($tag, 3);
                array_push($this->$n, $this->data);
                $this->data = false;
                break;
            case 'wp:author':
                if (!empty($this->data['author_login']))
                    $this->authors[$this->data['author_login']] = $this->data;
                $this->data = false;
                break;
            case 'wp:base_site_url':
                $this->base_url = $this->cdata;
                break;
            case 'wp:wxr_version':
                $this->wxr_version = $this->cdata;
                break;

            default:
                if ($this->in_sub_tag) {
                    $this->sub_data[$this->in_sub_tag] = !empty($this->cdata) ? $this->cdata : '';
                    $this->in_sub_tag = false;
                } else if ($this->in_tag) {
                    $this->data[$this->in_tag] = !empty($this->cdata) ? $this->cdata : '';
                    $this->in_tag = false;
                }
        }

        $this->cdata = false;
    }
}

/**
 * Parser that uses regular expressions. 
 * Fallback for installs without an XML parser.
 */
class RegexParser
{
    var $authors = array();
    var $posts = array();
    var $categories = array();
    var $tags = array();
    var $terms = array();
    var $base_url = '';

    function __construct()
    {
        $this->has_gzip = is_callable('gzopen');
    }

    function parse($file)
    {
        $wxr_version = $in_post = false;
        $post = '';

        $fp = $this->fopen($file, 'r');
        if ($fp) {
            while (!$this->feof($fp)) {
                $importline = rtrim($this->fgets($fp));

                if (!$wxr_version && preg_match('|<wp:wxr_version>(\d+\.\d+)</wp:wxr_version>|', $importline, $version))
                    $wxr_version = $version[1];

                if (false !== strpos($importline, '<wp:base_site_url>')) {
                    preg_match('|<wp:base_site_url>(.*?)</wp:base_site_url>|is', $importline, $url);
                    $this->base_url = $url[1];
                    continue;
                }
                if (false !== strpos($importline, '<wp:category>')) {
                    preg_match('|<wp:category>(.*?)</wp:category>|is', $importline, $category);
                    $this->categories[] = $this->process_category($category[1]);
                    continue;
                }
                if (false !== strpos($importline, '<wp:tag>')) {
                    preg_match('|<wp:tag>(.*?)</wp:tag>|is', $importline, $tag);
                    $this->tags[] = $this->process_tag($tag[1]);
                    continue;
                }
                if (false !== strpos($importline, '<wp:term>')) {
                    preg_match('|<wp:term>(.*?)</wp:term>|is', $importline, $term);
                    $this->terms[] = $this->process_term($term[1]);
                    continue;
                }
                if (false !== strpos($importline, '<wp:author>')) {
                    preg_match('|<wp:author>(.*?)</wp:author>|is', $importline, $author);
                    $a = $this->process_author($author[1]);
                    $this->authors[$a['author_login']] = $a;
                    continue;
                }
                if (false !== strpos($importline, '<item>')) {
                    $post = '';
                    $in_post = true;
                    continue;
                }
                if (false !== strpos($importline, '</item>')) {
                    $in_post = false;
                    $this->posts[] = $this->process_post($post);
                    continue;
                }
                if ($in_post) {
                    $post .= $importline . "\n";
                }
            }

            $this->fclose($fp);
        }

        if (!$wxr_version)
            return new \Exception('WXR_parse_error');

        return array(
            'authors' => $this->authors,
            'posts' => $this->posts,
            'categories' => $this->categories,
            'tags' => $this->tags,
            'terms' => $this->terms,
            'base_url' => $this->base_url,
            'version' => $wxr_version
        );
    }

    function get_tag($string, $tag)
    {
        preg_match("|<$tag.*?>(.*?)</$tag>|is", $string, $return);
        if (isset($return[1])) {
            if (substr($return[1], 0, 9) == '<![CDATA[') {
                if (strpos($return[1], ']]]]><![CDATA[>') !== false) {
                    preg_match_all('|<!\[CDATA\[(.*?)\]\]>|s', $return[1], $matches);
                    $return = '';
                    foreach ($matches[1] as $match)
                        $return .= $match;
                } else {
                    $return = preg_replace('|^<!\[CDATA\[(.*)\]\]>$|s', '$1', $return[1]);
                }
            } else {
                $return = $return[1];
            }
        } else {
            $return = '';
        }
        return $return;
    }

    function process_category($c)
    {
        return array(
            'term_id' => $this->get_tag($c, 'wp:term_id'),
            'cat_name' => $this->get_tag($c, 'wp:cat_name'),
            'category_nicename'    => $this->get_tag($c, 'wp:category_nicename'),
            'category_parent' => $this->get_tag($c, 'wp:category_parent'),
            'category_description' => $this->get_tag($c, 'wp:category_description'),
        );
    }

    function process_tag($t)
    {
        return array(
            'term_id' => $this->get_tag($t, 'wp:term_id'),
            'tag_name' => $this->get_tag($t, 'wp:tag_name'),
            'tag_slug' => $this->get_tag($t, 'wp:tag_slug'),
            'tag_description' => $this->get_tag($t, 'wp:tag_description'),
        );
    }

    function process_term($t)
    {
        return array(
            'term_id' => $this->get_tag($t, 'wp:term_id'),
            'term_taxonomy' => $this->get_tag($t, 'wp:term_taxonomy'),
            'slug' => $this->get_tag($t, 'wp:term_slug'),
            'term_parent' => $this->get_tag($t, 'wp:term_parent'),
            'term_name' => $this->get_tag($t, 'wp:term_name'),
            'term_description' => $this->get_tag($t, 'wp:term_description'),
        );
    }

    function process_author($a)
    {
        return array(
            'author_id' => $this->get_tag($a, 'wp:author_id'),
            'author_login' => $this->get_tag($a, 'wp:author_login'),
            'author_email' => $this->get_tag($a, 'wp:author_email'),
            'author_display_name' => $this->get_tag($a, 'wp:author_display_name'),
            'author_first_name' => $this->get_tag($a, 'wp:author_first_name'),
            'author_last_name' => $this->get_tag($a, 'wp:author_last_name'),
        );
    }

    function process_post($post)
    {
        $post_id        = $this->get_tag($post, 'wp:post_id');
        $post_title     = $this->get_tag($post, 'title');
        $post_date      = $this->get_tag($post, 'wp:post_date');
        $post_date_gmt  = $this->get_tag($post, 'wp:post_date_gmt');
        $comment_status = $this->get_tag($post, 'wp:comment_status');
        $ping_status    = $this->get_tag($post, 'wp:ping_status');
        $status         = $this->get_tag($post, 'wp:status');
        $post_name      = $this->get_tag($post, 'wp:post_name');
        $post_parent    = $this->get_tag($post, 'wp:post_parent');
        $menu_order     = $this->get_tag($post, 'wp:menu_order');
        $post_type      = $this->get_tag($post, 'wp:post_type');
        $post_password  = $this->get_tag($post, 'wp:post_password');
        $is_sticky      = $this->get_tag($post, 'wp:is_sticky');
        $guid           = $this->get_tag($post, 'guid');
        $post_author    = $this->get_tag($post, 'dc:creator');

        $post_excerpt = $this->get_tag($post, 'excerpt:encoded');
        $post_excerpt = preg_replace_callback('|<(/?[A-Z]+)|', array(&$this, '_normalize_tag'), $post_excerpt);
        $post_excerpt = str_replace('<br>', '<br />', $post_excerpt);
        $post_excerpt = str_replace('<hr>', '<hr />', $post_excerpt);

        $post_content = $this->get_tag($post, 'content:encoded');
        $post_content = preg_replace_callback('|<(/?[A-Z]+)|', array(&$this, '_normalize_tag'), $post_content);
        $post_content = str_replace('<br>', '<br />', $post_content);
        $post_content = str_replace('<hr>', '<hr />', $post_content);

        $postdata = compact(
            'post_id',
            'post_author',
            'post_date',
            'post_date_gmt',
            'post_content',
            'post_excerpt',
            'post_title',
            'status',
            'post_name',
            'comment_status',
            'ping_status',
            'guid',
            'post_parent',
            'menu_order',
            'post_type',
            'post_password',
            'is_sticky'
        );

        $attachment_url = $this->get_tag($post, 'wp:attachment_url');
        if ($attachment_url)
            $postdata['attachment_url'] = $attachment_url;

        preg_match_all('|<category domain="([^"]+?)" nicename="([^"]+?)">(.+?)</category>|is', $post, $terms, PREG_SET_ORDER);
        foreach ($terms as $t) {
            $post_terms[] = array(
                'slug' => $t[2],
                'domain' => $t[1],
                'name' => str_replace(array('<![CDATA[', ']]>'), '', $t[3]),
            );
        }
        if (!empty($post_terms)) $postdata['terms'] = $post_terms;

        preg_match_all('|<wp:comment>(.+?)</wp:comment>|is', $post, $comments);
        $comments = $comments[1];
        if ($comments) {
            foreach ($comments as $comment) {
                preg_match_all('|<wp:commentmeta>(.+?)</wp:commentmeta>|is', $comment, $commentmeta);
                $commentmeta = $commentmeta[1];
                $c_meta = array();
                foreach ($commentmeta as $m) {
                    $c_meta[] = array(
                        'key' => $this->get_tag($m, 'wp:meta_key'),
                        'value' => $this->get_tag($m, 'wp:meta_value'),
                    );
                }

                $post_comments[] = array(
                    'comment_id' => $this->get_tag($comment, 'wp:comment_id'),
                    'comment_author' => $this->get_tag($comment, 'wp:comment_author'),
                    'comment_author_email' => $this->get_tag($comment, 'wp:comment_author_email'),
                    'comment_author_IP' => $this->get_tag($comment, 'wp:comment_author_IP'),
                    'comment_author_url' => $this->get_tag($comment, 'wp:comment_author_url'),
                    'comment_date' => $this->get_tag($comment, 'wp:comment_date'),
                    'comment_date_gmt' => $this->get_tag($comment, 'wp:comment_date_gmt'),
                    'comment_content' => $this->get_tag($comment, 'wp:comment_content'),
                    'comment_approved' => $this->get_tag($comment, 'wp:comment_approved'),
                    'comment_type' => $this->get_tag($comment, 'wp:comment_type'),
                    'comment_parent' => $this->get_tag($comment, 'wp:comment_parent'),
                    'comment_user_id' => $this->get_tag($comment, 'wp:comment_user_id'),
                    'commentmeta' => $c_meta,
                );
            }
        }
        if (!empty($post_comments)) $postdata['comments'] = $post_comments;

        preg_match_all('|<wp:postmeta>(.+?)</wp:postmeta>|is', $post, $postmeta);
        $postmeta = $postmeta[1];
        if ($postmeta) {
            foreach ($postmeta as $p) {
                $post_postmeta[] = array(
                    'key' => $this->get_tag($p, 'wp:meta_key'),
                    'value' => $this->get_tag($p, 'wp:meta_value'),
                );
            }
        }
        if (!empty($post_postmeta)) $postdata['postmeta'] = $post_postmeta;

        return $postdata;
    }

    function _normalize_tag($matches)
    {
        return '<' . strtolower($matches[1]);
    }

    function fopen($filename, $mode = 'r')
    {
        if ($this->has_gzip)
            return gzopen($filename, $mode);
        return fopen($filename, $mode);
    }

    function feof($fp)
    {
        if ($this->has_gzip)
            return gzeof($fp);
        return feof($fp);
    }

    function fgets($fp, $len = 8192)
    {
        if ($this->has_gzip)
            return gzgets($fp, $len);
        return fgets($fp, $len);
    }

    function fclose($fp)
    {
        if ($this->has_gzip)
            return gzclose($fp);
        return fclose($fp);
    }
}