🎨 add redis feature

app/usecases/item_usecase.py

@@ -2,12 +2,28 @@
 
 from app.repositories import item_repository
 from app.schemas import item_schema
+import redis
+import json
+from app.utils.db_utils import AlchemyEncoder
 
 def get_items(db: Session, skip: int = 0, limit: int = 100):
     return item_repository.get_items(db, skip=skip, limit=limit)
 
 def get_item(db: Session, item_id: int):
-    return item_repository.get_item(db, item_id=item_id)
+    r = redis.Redis()
+    redis_val = r.hgetall(f"item:{item_id}")
+    print(len(redis_val))
+    if (redis_val is None or len(redis_val) < 1):
+        print('fetching data from database')
+        item = item_repository.get_item(db, item_id=item_id)
+
+        itemdetail = {f"data":json.dumps(item, cls=AlchemyEncoder)}
+        r.hmset(f"item:{item.id}", itemdetail)
+        return item
+    else:
+        print('fetching data from redis')
+        item = json.loads(r.hget(f"item:{item_id}", "data"))
+        return item
 
 def create_user_item(db: Session, item: item_schema.ItemCreate, user_id: int):
     return item_repository.create_user_item(db=db, item=item, user_id=user_id)

app/utils/db_utils.py

@@ -0,0 +1,20 @@
+import json
+from sqlalchemy.ext.declarative import DeclarativeMeta
+
+class AlchemyEncoder(json.JSONEncoder):
+
+    def default(self, obj):
+        if isinstance(obj.__class__, DeclarativeMeta):
+            # an SQLAlchemy class
+            fields = {}
+            for field in [x for x in dir(obj) if not x.startswith('_') and x != 'metadata']:
+                data = obj.__getattribute__(field)
+                try:
+                    json.dumps(data) # this will fail on non-encodable values, like other classes
+                    fields[field] = data
+                except TypeError:
+                    fields[field] = None
+            # a json-encodable dict
+            return fields
+
+        return json.JSONEncoder.default(self, obj)

requirements.txt

@@ -8,4 +8,5 @@ pymysql
 pytest
 pytest-cov
 uvicorn
-faker
+faker
+redis