logic behind creating bookmark checksum in google chrome

Question

How i can add a new bookmark entry in chrome bookmarkfile?. My requirement is, i need to add a bookmark entry through my application. Please specify the logic behind creating checksum(MD5).

Answer 1

Regardless of the safety/hackishness of doing it, here's how:

1. Make sure Chrome is closed.
2. Delete (or rename) Bookmarks.bak
3. Remove the checksum entry entirely from Bookmarks
4. Edit the Bookmarks JSON to your hearts content
5. Reopen Chrome

When presented with no backups and no checksum, Chrome will use the new JSON and generate a new checksum.

If you would like to do this more seamlessly / less aggressively, you can just look at how they generate the checksum in the original source code and implement the same algorithm (see here, on line 57).

Of course, keep in mind that Google can change things that could break compatibility. However, this does work, I just did it in a Java app I wrote.

Answer 2

Obviously this is hackish and only meant for people who know what they are doing, but, since Chrome Mobile does not let the user export/import their own bookmarks (not exactly user-friendly!), sometimes there's no choice - imagine having to clean up a Bookmarks file with thousands of entries by hand.

Anyway, here's a working Python implementation:

roots = ['bookmark_bar', 'other', 'synced']

def checksum_bookmarks(bookmarks):
    md5 = hashlib.md5()

    def checksum_node(node):
        md5.update(node['id'].encode())
        md5.update(node['name'].encode('utf-16le'))
        if node['type'] == 'url':
            md5.update(b'url')
            md5.update(node['url'].encode())
        else:
            md5.update(b'folder')
            if 'children' in node:
                for c in node['children']:
                    checksum_node(c)

    for root in roots:
        checksum_node(bookmarks['roots'][root])
    return md5.hexdigest()

As long as you're only adding bookmarks, you're probably fine, but for anything more complex (e.g. doing major cleanups, editing and deleting bookmarks, especially when multiple devices are involved), be sure to reset "Chrome Sync", or it will give you back all the deleted stuff, and an extra copy of each altered bookmark: Settings -> Sync -> Manage synced data -> Reset Sync