From fac25ab4f4e8fd19b45c5571414248750f4a1c69 Mon Sep 17 00:00:00 2001
From: Untone <anton.rewin@gmail.com>
Date: Tue, 7 May 2024 00:02:15 +0300
Subject: [PATCH] followers-fix

---
 resolvers/author.py  |  4 ++--
 services/cache.py    | 43 ++++++++++++++++++++++++++-----------------
 services/triggers.py |  7 +++----
 3 files changed, 31 insertions(+), 23 deletions(-)

diff --git a/resolvers/author.py b/resolvers/author.py
index da131bc3..8c2eebbd 100644
--- a/resolvers/author.py
+++ b/resolvers/author.py
@@ -9,7 +9,7 @@ from orm.shout import ShoutAuthor, ShoutTopic
 from orm.topic import Topic
 from resolvers.stat import author_follows_authors, author_follows_topics, get_with_stat
 from services.auth import login_required
-from services.cache import cache_author, cache_follower
+from services.cache import cache_author, cache_follow_author_change
 from services.db import local_session
 from services.encoders import CustomJSONEncoder
 from services.logger import root_logger as logger
@@ -332,7 +332,7 @@ async def get_author_followers(_, _info, slug: str):
         results = get_with_stat(q)
         if isinstance(results, list):
             for follower in results:
-                await cache_follower(follower.dict(), author.dict())
+                await cache_follow_author_change(follower.dict(), author.dict())
             logger.debug(f"@{slug} cache updated with {len(results)} followers")
         return results
     except Exception as exc:
diff --git a/services/cache.py b/services/cache.py
index 50a8d1bc..273b666b 100644
--- a/services/cache.py
+++ b/services/cache.py
@@ -94,15 +94,15 @@ async def cache_follows(follower: dict, entity_type: str, entity: dict, is_inser
         await redis.execute("SET", redis_key, payload)
 
         # update follower's stats everywhere
-        author_str = await redis.execute("GET", f"author:{follower_id}")
-        if isinstance(author_str, str):
-            author = json.loads(author_str)
-            author["stat"][f"{entity_type}s"] = len(follows)
-            await cache_author(author)
+        follower_str = await redis.execute("GET", f"author:{follower_id}")
+        if isinstance(follower_str, str):
+            follower = json.loads(follower_str)
+            follower["stat"][f"{entity_type}s"] = len(follows)
+            await cache_author(follower)
     return follows
 
 
-async def cache_follower(follower: dict, author: dict, is_insert=True):
+async def cache_follow_author_change(follower: dict, author: dict, is_insert=True):
     author_id = author.get("id")
     follower_id = follower.get("id")
     followers = []
@@ -110,26 +110,35 @@ async def cache_follower(follower: dict, author: dict, is_insert=True):
         redis_key = f"author:{author_id}:followers"
         followers_str = await redis.execute("GET", redis_key)
         followers = json.loads(followers_str) if isinstance(followers_str, str) else []
-        if is_insert and not any([int(f["id"]) == author_id for f in followers]):
+
+        # Remove the author from the list of followers, if present
+        followers = [f for f in followers if f["id"] != author_id]
+
+        # If inserting, add the new follower to the list if not already present
+        if is_insert and not any(f["id"] == follower_id for f in followers):
             followers.append(follower)
+
+        # Remove the follower from the list if not inserting and present
         else:
-            followers = [e for e in followers if int(e["id"]) != author_id]
+            followers = [f for f in followers if f["id"] != follower_id]
 
-        followers = [
-            dict(d)
-            for d in set(tuple(tuple(k, v) for k, v in d.items()) for d in followers)
-        ]
+        # Ensure followers are unique based on their 'id' field
+        followers = list({f["id"]: f for f in followers}.values())
+
+        # Update follower's stats everywhere
+        follower_str = await redis.execute("GET", f"author:{follower_id}")
+        if isinstance(follower_str, str):
+            follower = json.loads(follower_str)
+            follower["stat"]["followers"] = len(followers)
+            await cache_author(follower)
 
-        author_str = await redis.execute("GET", f"author:{follower_id}")
-        if isinstance(author_str, str):
-            author = json.loads(author_str)
-            author["stat"]["followers"] = len(followers)
-            await cache_author(author)
         payload = json.dumps(followers, cls=CustomJSONEncoder)
         await redis.execute("SET", redis_key, payload)
+
     return followers
 
 
+
 async def cache_topic(topic_dict: dict):
     # update stat all field for followers' caches in <topics> list
     followers = (
diff --git a/services/triggers.py b/services/triggers.py
index e7c27039..0eace99a 100644
--- a/services/triggers.py
+++ b/services/triggers.py
@@ -8,7 +8,7 @@ from orm.reaction import Reaction
 from orm.shout import Shout, ShoutAuthor
 from orm.topic import Topic, TopicFollower
 from resolvers.stat import get_with_stat
-from services.cache import cache_author, cache_follower, cache_follows
+from services.cache import cache_author, cache_follow_author_change, cache_follows
 from services.encoders import CustomJSONEncoder
 from services.logger import root_logger as logger
 from services.rediscache import redis
@@ -30,9 +30,8 @@ async def handle_author_follower_change(
     [follower] = get_with_stat(follower_query)
     if follower and author:
         await cache_author(author.dict())
-        await cache_author(follower.dict())
-        await cache_follows(follower.dict(), "author", author.dict(), is_insert)
-        await cache_follower(follower.dict(), author.dict(), is_insert)
+        await cache_follows(follower.dict(), "author", author.dict(), is_insert) # cache_author(follower_dict) inside
+        await cache_follow_author_change(follower.dict(), author.dict(), is_insert) # cache_author(follower_dict) inside
 
 
 async def handle_topic_follower_change(