Long story short: this is not trivial.

Disqus is a popular service that provides commenting functionality. All you need to do for your HTML page to have embedded discussion is to add a bit of javascript.

They have awesome importers from various blog engines. This blog was originally hosted on Blogspot, migration to static blog generated by Octopress required me to search for alternative commenting facilities and I decided to use disqus (is there anything else, really?) Now I switched to WordPress and I wanted my comments back.

Disqus does provide the ability to export all the comments in a XML file. Quick Google search told me that it was possible to get the comments quite easily into WordPress by converting the disqus dump into WXR, but it is not really that easy. WordPress will ignore the post if it is already there and will not import comments. There’s a plugin that imports disqus comments, but I wanted full support of nested comments and little to no PHP coding.

I dumped all the wordpress database locally and hacked up a script that reads the comments.xml file and puts the necessary data into the database. The script needs access to some sort of a database in order to figure out the post_id for each post and generate the comment identifiers for correct nesting.

#!/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])

...
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'])
...

And the script itself runs on an uncompressed disqus XML. The script will skip all pages that it could not find the URLs for:

$ python wp-import-disqus.py comments.xml
Skipping comment for http://rtg.in.ua/app/acer-exif-fixup/index.html

After script finished I dumped the comments table and uploaded it via the phpmyadmin interface.

$ mysqldump -h lab rtginua6_wp1 wp_comments > wp_comments.sql

This resulted in all 140 comments being correctly imported in a correct encoding and properly nested.

If you happen to know a better way to import comments, feel free to provide the links to alternative solutions.

while not keypressed

Importing disqus comments into WordPress