chore: add SQLALCHEMY_POOL_USE_LIFO option and missing SQLALCHEMY_POOL_PRE_PING env default value. (#22371)

api/configs/middleware/__init__.py

@@ -162,6 +162,11 @@ class DatabaseConfig(BaseSettings):
         default=3600,
     )
 
+    SQLALCHEMY_POOL_USE_LIFO: bool = Field(
+        description="If True, SQLAlchemy will use last-in-first-out way to retrieve connections from pool.",
+        default=False,
+    )
+
     SQLALCHEMY_POOL_PRE_PING: bool = Field(
         description="If True, enables connection pool pre-ping feature to check connections.",
         default=False,
@@ -199,6 +204,7 @@ class DatabaseConfig(BaseSettings):
             "pool_recycle": self.SQLALCHEMY_POOL_RECYCLE,
             "pool_pre_ping": self.SQLALCHEMY_POOL_PRE_PING,
             "connect_args": connect_args,
+            "pool_use_lifo": self.SQLALCHEMY_POOL_USE_LIFO,
         }
 
 

api/tests/unit_tests/configs/test_dify_config.py

@@ -88,6 +88,7 @@ def test_flask_configs(monkeypatch):
         "pool_pre_ping": False,
         "pool_recycle": 3600,
         "pool_size": 30,
+        "pool_use_lifo": False,
     }
 
     assert config["CONSOLE_WEB_URL"] == "https://example.com"

docker/.env.example

@@ -214,6 +214,10 @@ SQLALCHEMY_POOL_SIZE=30
 SQLALCHEMY_POOL_RECYCLE=3600
 # Whether to print SQL, default is false.
 SQLALCHEMY_ECHO=false
+# If True, will test connections for liveness upon each checkout
+SQLALCHEMY_POOL_PRE_PING=false
+# Whether to enable the Last in first out option or use default FIFO queue if is false
+SQLALCHEMY_POOL_USE_LIFO=false
 
 # Maximum number of connections to the database
 # Default is 100

docker/docker-compose.yaml

@@ -56,6 +56,8 @@ x-shared-env: &shared-api-worker-env
   SQLALCHEMY_POOL_SIZE: ${SQLALCHEMY_POOL_SIZE:-30}
   SQLALCHEMY_POOL_RECYCLE: ${SQLALCHEMY_POOL_RECYCLE:-3600}
   SQLALCHEMY_ECHO: ${SQLALCHEMY_ECHO:-false}
+  SQLALCHEMY_POOL_PRE_PING: ${SQLALCHEMY_POOL_PRE_PING:-false}
+  SQLALCHEMY_POOL_USE_LIFO: ${SQLALCHEMY_POOL_USE_LIFO:-false}
   POSTGRES_MAX_CONNECTIONS: ${POSTGRES_MAX_CONNECTIONS:-100}
   POSTGRES_SHARED_BUFFERS: ${POSTGRES_SHARED_BUFFERS:-128MB}
   POSTGRES_WORK_MEM: ${POSTGRES_WORK_MEM:-4MB}