Refactor datetime handling to include timezone

awareness

Updated the datetime usage in multiple models to include timezone
awareness by importing 'UTC' and applying it to the default_factory.

Author: Mithun Thomas

src/app/models/post.py

@@ -1,5 +1,5 @@
 import uuid as uuid_pkg
-from datetime import datetime
+from datetime import datetime, UTC
 
 from sqlalchemy import String, DateTime, ForeignKey
 from sqlalchemy.orm import Mapped, mapped_column
@@ -21,7 +21,7 @@ class Post(Base):
     media_url: Mapped[str | None] = mapped_column(String, default=None)
 
     created_at: Mapped[datetime] = mapped_column(
-        DateTime, default_factory=datetime.utcnow
+        DateTime(timezone=True), default_factory=lambda:  datetime.now(UTC)
     )
     updated_at: Mapped[datetime | None] = mapped_column(default=None)
     deleted_at: Mapped[datetime | None] = mapped_column(default=None)

src/app/models/rate_limit.py

@@ -1,5 +1,5 @@
 from typing import Optional
-from datetime import datetime
+from datetime import datetime, UTC
 
 from sqlalchemy import String, DateTime, ForeignKey, Integer
 from sqlalchemy.orm import Mapped, mapped_column
@@ -19,6 +19,6 @@ class RateLimit(Base):
     period: Mapped[int] = mapped_column(Integer, nullable=False)
 
     created_at: Mapped[datetime] = mapped_column(
-        DateTime, default_factory=datetime.utcnow
+        DateTime(timezone=True), default_factory=lambda:  datetime.now(UTC)
     )
     updated_at: Mapped[Optional[datetime]] = mapped_column(default=None)

src/app/models/tier.py

@@ -15,6 +15,6 @@ class Tier(Base):
     name: Mapped[str] = mapped_column(String, nullable=False, unique=True)
 
     created_at: Mapped[datetime] = mapped_column(
-        DateTime, default_factory=lambda:  datetime.now(UTC).replace(tzinfo=None)
+        DateTime(timezone=True), default_factory=lambda:  datetime.now(UTC)
     )
     updated_at: Mapped[Optional[datetime]] = mapped_column(default=None)

src/app/models/user.py

@@ -24,7 +24,7 @@ class User(Base):
         default_factory=uuid_pkg.uuid4, primary_key=True, unique=True
     )
     created_at: Mapped[datetime] = mapped_column(
-        DateTime, default_factory=lambda:  datetime.now(UTC).replace(tzinfo=None)
+        DateTime(timezone=True), default_factory=lambda:  datetime.now(UTC)
     )
     updated_at: Mapped[Optional[datetime]] = mapped_column(default=None)
     deleted_at: Mapped[Optional[datetime]] = mapped_column(default=None)