def found_in_intersect(status: Status, history: History,
rev_root_path: str) -> bool:
"""Whether wiki race end path was found in newly discovered links.
If the wiki race end path was discovered through a page both searches found (an intersection)
Results traversed path: path of current search + (path of reverse search).reversed()
This is because one computes forward based on links and the other backwards based on links_to
Finalize results: by sending the finalized results traversed path to status of the search & reverse search
Args:
status: Status of current search.
history: History of current search.
rev_root_path: The root_path of the same search going in reverse.
"""
status_rev = Status(status_db, rev_root_path)
intersection = history.traversed_intersection(status.root_path,
rev_root_path)
if intersection:
path_to_goal = history.intersection_path(status.root_path,
rev_root_path)
status.finalize_results(path_to_goal)
path_to_goal_rev = path_to_goal.copy()
path_to_goal_rev.reverse()
# also set results in the reverse search db
status_rev.finalize_results(path_to_goal_rev)
logger.info(
f"Intersection End link found!! path traversed and time to complete: {path_to_goal} or {path_to_goal_rev}"
)
return True
return False
def found_in_page(status: Status, history: History, all_links: List[str],
rev_root_path: str) -> bool:
"""Whether wiki race end path was found in newly discovered links.
If the wiki race end path was discovered on current page:
Results traversed path: end path appended to the current query page's traversed path.
Finalize results: by sending the finalized results traversed path to status of the search & reverse search
Args:
status: Status of current search.
history: History of current search.
all_links: List of new links discovered on current query page.
rev_root_path: The root_path of the same search going in reverse.
"""
status_rev = Status(status_db, rev_root_path)
if status.end_path in all_links:
path = history.traversed_path.copy()
path.append(status.end_path)
status.finalize_results(path)
path_rev = path.copy()
path_rev.reverse()
# also set results in the reverse search db
status_rev.finalize_results(path_rev)
logger.info(
f"End link found!! path traversed and time to complete: {path} or {path_rev}"
)
return True
return False
def find(root_path: str, start_path: str, rev_root_path: str, rev=False):
"""Celery task that plays wiki racer game.
This task only kicks off if the search is still active.
Sets history: Based on search status and current page bering queried.
Keeps track of visited: If a node is already visited do not visit again (prevent cycles)
Upon discovery of a new page: Scrape page for new links.
When new links obtained: Score links based on similarity to wiki race end path.
Track game completion: When wiki game end path is found in newly discovered links end the game.
If wiki page end game not found, send another task to find with:
start_path/query: [highest scoring page discovered so far].
Args:
root_path: Search key composed of wiki racer start page and end page.
start_path: Page being queried.
rev_root_path: The path reversed of this one.
rev: are we going in reverse?
"""
# Weird edge cases:
if not root_path or not start_path or not rev_root_path:
raise ValueError(
f"You need to specify root_path, start_path, and rev_root_path")
status = Status(status_db, root_path)
# Dont start find if task is done
if not status.is_active():
return
# Weird edge cases:
if status.start_path == status.end_path:
result = [start_path]
status.finalize_results(result)
status_rev = Status(status_db, rev_root_path)
status_rev.finalize_results(result)
return
# Populates history
history = History(
status,
visited_db,
scores_db,
traversed_db,
start_path,
)
if start_path == status.start_path:
history.traversed_path = [status.start_path]
if not history.is_visited(start_path):
history.add_to_visited(start_path)
# links from wikipedia
all_links = Wikipedia(status, start_path, rev).scrape_page()
# return if found in links on current page before bothering to score them
if found_in_page(status, history, all_links, rev_root_path):
return
# score found links
nlp_scores = NLP(status, history).score_links(all_links)
# set their new traversed paths
history.bulk_add_to_new_links_traversed_paths(all_links)
# add them onto scores set
history.bulk_add_to_scores(nlp_scores)
# return if found in the intersection between forward and reverse search
if found_in_intersect(status, history, rev_root_path):
return
# Dont kick off next find find if task is done or no more pages left to search
if not status.is_active() or len(history.scores) < 1:
return
# kick off another find task with highest scoring page found so far
app.send_task(
"tasks.find",
kwargs=dict(
root_path=root_path,
start_path=history.next_highest_score(),
rev_root_path=rev_root_path,
rev=rev,
),
queue="find_rev" if rev else "find",
)