Disqus importer to WordPress

wp-import-disqus.py

#!/usr/bin/python
"""Quick and dirty hack to get disqus comments into WordPress DB"""

import sys
from datetime import datetime
from xml.etree import ElementTree as ET
import MySQLdb

ANONYMOUS_EMAIL = 'nobody@example.net'

# Database configuration
DATABASE = {
    'host': 'lab.lappyfamily.net',
    'user': 'rtg',
    'name': 'rtginua6_wp1',
}

# Admin information
ADMIN_INFO = {
    'comment_author': 'Roman Yepishev',
    'comment_author_email': 'roman.yepishev@yandex.ua',
    'user_id': 1
}

# Names used in disqus that represent administrator
ADMIN_ALIASES = set(['rtg', 'Roman', 'rye'])

class DisqusImporter(object):
    """
    Imports Disqus XML into MySQL database for WordPress
    """
    def __init__(self):
        self.wpdb = MySQLdb.connect(host=DATABASE['host'],
                                    user=DATABASE['user'],
                                    db=DATABASE['name'],
                                    charset='utf8')

        self.wp_post_url_to_id = {}

    def make_wordpress_url_map(self):
        """Creates URL->ID map for WordPress URLS"""
        cursor = self.wpdb.cursor()

        cursor.execute("""
            SELECT 
                guid, id
            FROM
                wp_posts
            WHERE
                post_type = 'post'
        """)

        for row in cursor:
            self.wp_post_url_to_id[row[0]] = row[1]

    def parse_disqus_comments(self, path):
        """Parse comments creating WP-like structure"""

        NS = '{http://disqus.com}'
        NS_DI = '{http://disqus.com/disqus-internals}'

        tree = ET.parse(path)
        root = tree.getroot()

        comments = {}
        thread_id_to_url = {}

        # Gathering post threads identifiers.
        # Each thread corresponds to a blog post
        for thread in root.findall(NS + 'thread'):
            dsq_id =  thread.attrib[NS_DI + 'id']
            link = thread.find(NS + 'link')

            thread_id_to_url[dsq_id] = link.text

        # Parsing posts
        for post in root.findall(NS + 'post'):
            dsq_id = post.attrib[NS_DI + 'id']

            thread_id = post.find(NS + 'thread').attrib[NS_DI + 'id']

            # If we don't have the mapping from post to
            # WordPress post ID, we can't # proceed with this comment
            thread_url = thread_id_to_url[thread_id]

            if thread_url not in self.wp_post_url_to_id:
                print "Skipping comment for {}".format(thread_url)
                continue

            created_at = post.find(NS + 'createdAt').text

            author = post.find(NS + 'author')
            email = author.find(NS + 'email').text
            name = author.find(NS + 'name').text

            parent = post.find(NS + 'parent')
            if parent is not None:
                parent_id = parent.attrib[NS_DI + 'id']
            else:
                parent_id = None

            # MySQL issues a warning if we stuff data in YYY-mm-ddTHH:MM:SSZ
            comment_date = datetime.strptime(created_at, '%Y-%m-%dT%H:%M:%SZ'
                                          ).strftime('%Y-%m-%d %H:%M:%S')

            
            comment_post_id = self.wp_post_url_to_id[thread_url]

            post_data = {
                'comment_post_ID': comment_post_id,
                'comment_content': post.find(NS + 'message').text,
                'comment_date': comment_date,
                'comment_date_gmt': comment_date,
                'comment_author': name,
                'comment_author_IP': post.find(NS + 'ipAddress').text,
                'comment_author_email': email if email else ANONYMOUS_EMAIL,
                'user_id': 0,
                'parent_id': parent_id,
                'children': []
            }

            # Fixup for my own comments
            if name in ADMIN_ALIASES:
                post_data.update(ADMIN_INFO)

            comments[dsq_id] = post_data

        # First pass - creating comment tree
        for comment in comments.values():
            if comment['parent_id']:
                parent_comment = comments[comment['parent_id']]
                parent_comment['children'].append(comment)

        # Second pass - dropping posts that are not toplevel
        # They are already in 'children'
        for comment_id in comments.keys():
            # If it is still here (we could have deleted it)
            if comment_id in comments:
                comment = comments[comment_id]
            else:
                continue

            if comment['parent_id']:
                del comments[comment_id]

        return comments

    def add_comment(self, comment, parent_id):
        """Add comment and all the child comments to the DB"""

        cursor = self.wpdb.cursor()

        comment['comment_parent'] = parent_id

        cursor.execute("""
                    INSERT INTO wp_comments (
                        comment_post_ID,      comment_author,
                        comment_author_email, comment_author_IP,
                        comment_date,         comment_date_gmt,
                        comment_content,      comment_parent,
                        user_id)
                    VALUES (
                        %(comment_post_ID)s, %(comment_author)s,
                        %(comment_author_email)s, %(comment_author_IP)s,
                        %(comment_date)s, %(comment_date_gmt)s,
                        %(comment_content)s, %(comment_parent)s,
                        %(user_id)s)
            """, comment
        )

        parent_id = cursor.lastrowid

        for item in comment['children']:
            self.add_comment(item, parent_id)

    def update_comment_count(self):
        """
        Synchronizes cached comment count with the actual number of
        comments
        """
        cursor = self.wpdb.cursor()
        # Update post counts
        cursor.execute("""
                UPDATE 
                    wp_posts AS p
                    LEFT JOIN (
                        SELECT 
                            comment_post_ID,
                            count(comment_post_ID) as comment_count
                        FROM
                            wp_comments
                        WHERE
                            comment_approved = '1'
                        GROUP BY comment_post_ID
                    ) as c 
                ON 
                    p.id = c.comment_post_ID
                SET
                    p.comment_count = c.comment_count
                WHERE
                    p.id = c.comment_post_ID
        """)

    def main(self, path):
        """Entry point"""
        self.make_wordpress_url_map()
        comments = self.parse_disqus_comments(path)

        for item in comments.values():
            self.add_comment(item, 0)

        self.update_comment_count()

if __name__ == "__main__":
    importer = DisqusImporter()
    importer.main(sys.argv[1])