def remove_tags_with_commas()

in pulseapi/tags/helpers.py [0:0]

• 15 lines of code
• 5 McCabe index (conditional complexity)

def remove_tags_with_commas(app, schema_editor):
    """
    This function analyses any tag for whether it contains
    commas. If it does, it splits on comma, trims the result,
    and then either creates a new tag, or uses an existing tag,
    to retag any entry that had a comma-encumbered tag (or tags).
    """

    tags_with_commas = Tag.objects.filter(name__contains=',')

    for tag in tags_with_commas:
        # Get all entries that use this tag right now, because
        # we're going to need to change what it points to.
        entries = Entry.objects.filter(tags__name=tag.name)

        # Create a list of plain string "tags" that we get by
        # resolving the comma(s) in our comma-laden tag.
        trimmed = tag.name.strip()
        splitlist = re.split(r'\s*,\s*', trimmed)
        filtered = list(filter(None, splitlist))

        # For each tag string we now have, update the entries that
        # used this tag so that they're tagged with the right thing
        # instead of our comma-encumbered tag.
        for tag_string in filtered:
            (retag, created) = Tag.objects.get_or_create(name=tag_string)
            for entry in entries:
                if retag in entry.tags.all():
                    continue
                else:
                    entry.tags.add(retag)

        # After updating all entries to use the new (set of) tag(s),
        # we can safely delete this offending comma-encumbered tag.
        tag.delete()