Function shortest_paths_route

sdow/server.py:84–153

Endpoint which returns a list of shortest paths between two Wikipedia pages. Args: source: The title of the page at which to start the search. target: The title of the page at which to end the search. Returns: dict: A JSON-ified dictionary containing the shortest paths (r

()

@app.route('/paths', methods=['POST'])
def shortest_paths_route():
  """Endpoint which returns a list of shortest paths between two Wikipedia pages.

    Args:
      source: The title of the page at which to start the search.
      target: The title of the page at which to end the search.

    Returns:
      dict: A JSON-ified dictionary containing the shortest paths (represented by a list of lists of
            page IDs) and the corresponding pages data (represented by a dictionary of page IDs).

    Raises:
      InvalidRequest: If either of the provided titles correspond to pages which do not exist.
  """
  start_time = time.time()

  # Look up the IDs for each page.
  try:
    (source_page_id, source_page_title,
     is_source_redirected) = database.fetch_page(request.json['source'])
  except ValueError:
    raise InvalidRequest(
        'Start page "{0}" does not exist. Please try another search.'.format(request.json['source']))

  try:
    (target_page_id, target_page_title,
     is_target_redirected) = database.fetch_page(request.json['target'])
  except ValueError:
    raise InvalidRequest(
        'End page "{0}" does not exist. Please try another search.'.format(request.json['target']))

  # Compute the shortest paths.
  paths = database.compute_shortest_paths(source_page_id, target_page_id)

  response = {
      'sourcePageTitle': source_page_title,
      'targetPageTitle': target_page_title,
      'isSourceRedirected': is_source_redirected,
      'isTargetRedirected': is_target_redirected,
  }

  # No paths found.
  if len(paths) == 0:
    logging.info('No paths found from {0} to {1}'.format(source_page_id, target_page_id))
    response['paths'] = []
    response['pages'] = []
  # Paths found
  else:
    # Get a list of all IDs.
    page_ids_set = set()
    for path in paths:
      for page_id in path:
        page_ids_set.add(str(page_id))

    response['paths'] = paths
    response['pages'] = fetch_wikipedia_pages_info(list(page_ids_set), database)