"""Asynchronous webscraping.
 """

 import asyncio

 import aiohttp

 from get_synchronous import LanguageInfluences
 from parse_html import parse


 class AsyncLanguageInfluences(LanguageInfluences):
     """Asynchronous version.
     """
     @asyncio.coroutine
     def get_url_content(self, url, name):
         """Get and parse the content of the URL.
         """
         if not url.startswith('/wiki/'):
             print('Skipping URL:', url)
             return None
         full_url = self.url_base + url
         print('fetching', full_url)
         http_response = yield from aiohttp.request('GET', full_url)
         html = (yield from http_response.read_and_close())
         return (yield from self.parse(html, url, name))

     @asyncio.coroutine
     def parse(self, html, url, name):
         """Parse and store in DB.
         """
         if html:
             content = parse(html)
             data = {'name': name, 'content': content}
             self.db[url] = data
             return content

     @asyncio.coroutine
     def work(self, content=None):
         """Process urls recursively.
         """
         if not content and self.start_url not in self.db:
             content = yield from self.get_url_content(self.start_url,
                                             self.start_name)
         if content and len(self.db) <= self.limit:
             for category in self.categories:
                 for url, names in content[category].items():
                     if not url or url == 'None':
                         continue
                     name = next(iter(names))
                     if url not in self.db:
                         content = yield from self.get_url_content(url, name)
                         yield from self.work(content)

 if __name__ == '__main__':

     def test():
         """Run and measure the runtime.
         """
         import timeit
         start = timeit.default_timer()
         langs = AsyncLanguageInfluences()
         loop = asyncio.get_event_loop()
         loop.run_until_complete(langs.work())
         duration = timeit.default_timer() - start
         print(duration)

     test()