def name_has_prefix(name, prefix):
prefixes = prefix.split()
for name_part in search_namify(name).split():
check_prefixes = prefixes
for prefix in check_prefixes:
if name_part.startswith(prefix):
prefixes.remove(prefix)
if len(prefixes) == 0:
return True
break
return False
def autocomplete(cls, prefix):
prefix = prefix.lower().strip()
# Go into memory and grab all (some?) of the caches for this
# prefix and earlier
cache_list = [SetQueryCache.fetch(cls.COMPLETE %prefix[:i+1]) for
i in range(len(prefix))]
best_data = set()
for prelen, cached_query in enumerate(cache_list):
if len(cached_query) > 0:
best_data = cached_query.results
else:
best_data = set(
filter(lambda an: ArtistName.name_has_prefix(an, prefix[:prelen+1]),
best_data))
cached_query.set(best_data)
cached_query.save()
cached = cache_list.pop() # Get the cache for the relevant prefix
if cached.need_fetch(cls.AC_FETCH_NUM):
# We have to fetch some keys from the datastore
if cached.cursor is None:
cached.cursor = {'lower': None, 'search': None}
# Prep the queries
lower_query = RawArtistName.query().filter(
ndb.AND(RawArtistName.lowercase_name >= prefix,
RawArtistName.lowercase_name < (prefix + u"\ufffd")))
search_query = RawArtistName.query().filter(
ndb.AND(RawArtistName.search_name >= prefix,
RawArtistName.search_name < (prefix + u"\ufffd")))
try:
# Try to continue an older query
num = cls.AC_FETCH_NUM - len(cached)
lower_raw_artists, lower_cursor, l_more = lower_query.fetch_page(
num, start_cursor=cached.cursor['lower'],
projection=[RawArtistName.artist_name])
search_raw_artists, search_cursor, s_more = search_query.fetch_page(
num, start_cursor=cached.cursor['search'],
projection=[RawArtistName.artist_name])
cache_results = cached.results
except db.BadRequestError:
# Unable to continue the older query. Run a new one.
lower_raw_artists, lower_cursor, l_more = lower_query.fetch_page(
num,
projection=[RawArtistName.artist_name])
search_raw_artists, search_cursor, s_more = search_query.fetch_page(
num,
projection=[RawArtistName.artist_name])
cache_results = set()
add_artists = (set(a.artist_name for a in search_raw_artists) |
set(a.artist_name for a in lower_raw_artists))
artist_names = cached.results | add_artists
# We've got a bunch of artistnames for this prefix, so let's
# update all of our cached queries: this one, and all supqueries
cached.extend_by(add_artists,
{'lower': lower_cursor, 'search': search_cursor},
l_more or s_more)
cached.save()
for cached_query in reversed(cache_list):
cached_query.extend(add_artists)
cached_query.save()
else:
# We don't have to fetch anything!
artist_names = cached.results
return sorted(artist_names, key=lambda x: search_namify(x))
