🐛 fix(flow.py): make description field nullable with a default value of None to allow empty descriptions

🐛 fix(user.py): make last_login_at field nullable to handle cases where user has not logged in yet
🐛 fix(user.py): set default values for optional fields in UserUpdate model to None to avoid unexpected behavior

src/backend/langflow/services/database/models/flow/flow.py

@@ -13,7 +13,7 @@ if TYPE_CHECKING:
 
 class FlowBase(SQLModelSerializable):
     name: str = Field(index=True)
-    description: Optional[str] = Field(index=True)
+    description: Optional[str] = Field(index=True, nullable=True, default=None)
     data: Optional[Dict] = Field(default=None, nullable=True)
 
     @validator("data")

src/backend/langflow/services/database/models/user/user.py

@@ -20,7 +20,7 @@ class User(SQLModelSerializable, table=True):
     is_superuser: bool = Field(default=False)
     create_at: datetime = Field(default_factory=datetime.utcnow)
     updated_at: datetime = Field(default_factory=datetime.utcnow)
-    last_login_at: Optional[datetime] = Field()
+    last_login_at: Optional[datetime] = Field(nullable=True)
     api_keys: list["ApiKey"] = Relationship(
         back_populates="user",
         sa_relationship_kwargs={"cascade": "delete"},
@@ -41,13 +41,13 @@ class UserRead(SQLModel):
     is_superuser: bool = Field()
     create_at: datetime = Field()
     updated_at: datetime = Field()
-    last_login_at: Optional[datetime] = Field()
+    last_login_at: Optional[datetime] = Field(nullable=True)
 
 
 class UserUpdate(SQLModel):
-    username: Optional[str]
-    profile_image: Optional[str]
-    password: Optional[str]
-    is_active: Optional[bool]
-    is_superuser: Optional[bool]
-    last_login_at: Optional[datetime]
+    username: Optional[str] = None
+    profile_image: Optional[str] = None
+    password: Optional[str] = None
+    is_active: Optional[bool] = None
+    is_superuser: Optional[bool] = None
+    last_login_at: Optional[datetime] = None