class FollowRecommendationsServicer(follows_pb2_grpc.FollowsServicer):
RECOMMENDERS = {
'surprise': SurpriseRecommender,
'cn': CNRecommender,
'graphdist': GraphDistanceRecommender,
}
DEFAULT_RECOMMENDER = 'graphdist'
ENV_VAR = 'FOLLOW_RECOMMENDER_METHOD'
DEFAULT_IMAGE = "https://upload.wikimedia.org/wikipedia/commons/8/89/Portrait_Placeholder.png"
def __init__(self, logger, users_util, db_stub):
self._logger = logger
self._users_util = users_util
self._db_stub = db_stub
self._recommender_util = RecommendersUtil(
logger, db_stub, self.DEFAULT_RECOMMENDER, self.ENV_VAR, self.RECOMMENDERS)
# self.active_recommenders contains one or more recommender system
# objects (out of the constructors in self.RECOMMENDERS).
self.active_recommenders = self._recommender_util._get_active_recommenders()
def _get_recommendations(self, user_id):
'''Get recommendations for users for the given user_id to follow, using
the one or more systems in self.active_recommenders. Could return empty
list if there are no good recommendations.'''
# TODO(iandioch): Allow for combining the results of multiple systems
# in a smarter way than just concatenation.
for r in self.active_recommenders:
yield from r.get_recommendations(user_id)
def GetFollowRecommendations(self, request, context):
self._logger.debug('GetFollowRecommendations, user_id = %s',
request.user_id)
resp = recommend_follows_pb2.FollowRecommendationResponse()
user = self._users_util.get_user_from_db(global_id=request.user_id)
if user is None:
resp.result_type = \
general_pb2.ResultType.ERROR
resp.error = "Could not find the given user_id."
return resp
if not (user.host is None or user.host == ""):
resp.result_type = \
general_pb2.ResultType.ERROR
resp.error = "Can only give recommendations for local users."
return resp
resp.result_type = general_pb2.ResultType.OK
# Get the recommendations and package them into proto.
for p in self._get_recommendations(user.global_id):
a = self._users_util.get_or_create_user_from_db(global_id=p[0])
user_obj = resp.results.add()
user_obj.handle = a.handle
user_obj.host = a.host
user_obj.display_name = a.display_name
user_obj.bio = a.bio
user_obj.image = self.DEFAULT_IMAGE
user_obj.global_id = a.global_id
return resp
def UpdateFollowRecommendations(self, request, context):
self._logger.debug('UpdateFollowRecommendations, %d following %d: %s',
request.follower,
request.followed,
request.following)
resp = recommend_follows_pb2.UpdateFollowRecommendationsResponse()
for r in self.active_recommenders:
r.update_recommendations(request.follower,
request.followed,
request.following)
return resp
class PostRecommendationsServicer(recommend_posts_pb2_grpc.PostRecommendationsServicer):
RECOMMENDERS = {
'random': RandomRecommender,
'cosine': CosineRecommender,
}
DEFAULT_RECOMMENDER = 'random'
ENV_VAR = 'POSTS_RECOMMENDER_METHOD'
MAX_RECOMMENDATIONS = 50
DEFAULT_IMAGE = "https://upload.wikimedia.org/wikipedia/commons/8/89/Portrait_Placeholder.png"
def __init__(self, users_util, logger, db_stub):
self._logger = logger
self._db_stub = db_stub
self._users_util = users_util
self._activ_util = ActivitiesUtil(logger, db_stub)
self._recommender_util = RecommendersUtil(
logger, db_stub, self.DEFAULT_RECOMMENDER, self.ENV_VAR, self.RECOMMENDERS)
# self.active_recommenders contains one or more recommender system
# objects (out of the constructors in self.RECOMMENDERS).
self.active_recommenders = self._recommender_util._get_active_recommenders()
def Get(self, request, context):
self._logger.debug('Get PostRecommendations, user_id = %s',
request.user_id)
resp = recommend_posts_pb2.PostRecommendationsResponse()
recommended_posts = []
post_ids = set()
max_posts_per_r = self.MAX_RECOMMENDATIONS // len(
self.active_recommenders)
for r in self.active_recommenders:
r_posts, error = r.get_recommendations(
request.user_id, max_posts_per_r)
if error:
resp.result_type = \
recommend_posts_pb2.PostRecommendationsResponse.ERROR
resp.message = error
return resp
recommended_posts.append(r_posts)
# Join recommendations together, with the highest recommended first
posts = []
for i in range(max_posts_per_r + 1):
for r_p in recommended_posts:
# See proto/Feed.Post and proto/database.PostsEntry
if i < len(r_p):
author = self._users_util.get_user_from_db(
global_id=r_p[i].author_id)
if author == None:
resp.result_type = \
recommend_posts_pb2.PostRecommendationsResponse.ERROR
resp.message = "Post Author could not be found"
return resp
post_obj = resp.results.add()
post_obj.global_id = r_p[i].global_id
post_obj.author = author.handle
post_obj.author_host = author.host
post_obj.author_id = r_p[i].author_id
post_obj.title = r_p[i].title
post_obj.body = r_p[i].body
post_obj.published = self._activ_util.timestamp_to_rfc(
r_p[i].creation_datetime)
post_obj.likes_count = r_p[i].likes_count
post_obj.bio = author.bio
post_obj.image = self.DEFAULT_IMAGE
post_obj.is_liked = r_p[i].is_liked
post_obj.is_followed = r_p[i].is_followed
post_obj.shares_count = r_p[i].shares_count
post_obj.summary = r_p[i].summary
tags = self._recommender_util.split_tags(r_p[i].tags)
post_obj.tags.extend(tags)
resp.result_type = \
recommend_posts_pb2.PostRecommendationsResponse.OK
return resp
def UpdateModel(self, request, context):
self._logger.debug('UpdateModel PostRecommendations, user_id = %s',
request.user_id)
resp = recommend_posts_pb2.PostRecommendationsResponse()
for r in self.active_recommenders:
error = r.update_model(request.user_id, request.article_id)
if error:
resp.result_type = \
recommend_posts_pb2.PostRecommendationsResponse.ERROR
resp.message = error
return resp
resp.result_type = \
recommend_posts_pb2.PostRecommendationsResponse.OK
return resp
def AddPost(self, request, context):
self._logger.debug('UpdateModel PostRecommendations, user_id = %s',
request.author_id)
resp = recommend_posts_pb2.PostRecommendationsResponse()
for r in self.active_recommenders:
error = r.add_post(request)
if error:
resp.result_type = \
recommend_posts_pb2.PostRecommendationsResponse.ERROR
resp.message = error
return resp
resp.result_type = \
recommend_posts_pb2.PostRecommendationsResponse.OK
return resp