def _filter_link_tag_data(self, source, soup, data, url):
link = FILTER_MAPS['<STR_LIT>'][source]<EOL>html = soup.find_all('<STR_LIT>', {link['<STR_LIT:key>']: link['<STR_LIT>']})<EOL>if link['<STR_LIT:type>'] == '<STR_LIT:url>':<EOL><INDENT>for line in html:<EOL><INDENT>data['<STR_LIT:url>'] = line.get('<STR_LIT>')<EOL><DEDENT><DEDENT>else:<EOL><INDENT>for line in html:<EOL><INDENT>data['<STR_LIT>'].append({<EOL>'<STR_LIT:src>': urljoin(url, line.get('<STR_LIT>')),<EOL>'<STR_LIT:type>': link['<STR_LIT:type>'],<EOL>})<EOL><DEDENT><DEDENT>
This method filters the web page content for link tags that match patterns given in the ``FILTER_MAPS``

        :param source: The key of the meta dictionary in ``FILTER_MAPS['link']``
        :type source: string
        :param soup: BeautifulSoup instance to find meta tags
        :type soup: instance
        :param data: The response dictionary to manipulate
        :type data: (dict)
        :param url: URL used for making an absolute url
        :type url: string