ref: Add ruff rules for datetime (DTZ) (#4003)

Add ruff rules for datetime (DTZ)

src/backend/base/langflow/api/v1/files.py

@@ -1,5 +1,5 @@
 import hashlib
-from datetime import datetime
+from datetime import datetime, timezone
 from http import HTTPStatus
 from io import BytesIO
 from pathlib import Path
@@ -57,7 +57,7 @@ async def upload_file(
             raise HTTPException(status_code=403, detail="You don't have access to this flow")
 
         file_content = await file.read()
-        timestamp = datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
+        timestamp = datetime.now(tz=timezone.utc).astimezone().strftime("%Y-%m-%d_%H-%M-%S")
         file_name = file.filename or hashlib.sha256(file_content).hexdigest()
         full_file_name = f"{timestamp}_{file_name}"
         folder = flow_id_str

src/backend/base/langflow/api/v1/flows.py

@@ -390,7 +390,7 @@ async def download_multiple_file(
         zip_stream.seek(0)
 
         # Generate the filename with the current datetime
-        current_time = datetime.now().strftime("%Y%m%d_%H%M%S")
+        current_time = datetime.now(tz=timezone.utc).astimezone().strftime("%Y%m%d_%H%M%S")
         filename = f"{current_time}_langflow_flows.zip"
 
         return StreamingResponse(

src/backend/base/langflow/initial_setup/setup.py

@@ -390,10 +390,9 @@ def get_project_data(project):
     project_is_component = project.get("is_component")
     project_updated_at = project.get("updated_at")
     if not project_updated_at:
-        project_updated_at = datetime.now(tz=timezone.utc).isoformat()
+        updated_at_datetime = datetime.now(tz=timezone.utc)
-        updated_at_datetime = datetime.strptime(project_updated_at, "%Y-%m-%dT%H:%M:%S.%f%z")
     else:
-        updated_at_datetime = datetime.strptime(project_updated_at, "%Y-%m-%dT%H:%M:%S.%f")
+        updated_at_datetime = datetime.fromisoformat(project_updated_at)
     project_data = project.get("data")
     project_icon = project.get("icon")
     project_icon = demojize(project_icon) if project_icon and purely_emoji(project_icon) else ""
@@ -528,14 +527,14 @@ def load_flows_from_directory():
                         if hasattr(existing, key):
                             # flow dict from json and db representation are not 100% the same
                             setattr(existing, key, value)
-                    existing.updated_at = datetime.utcnow()
+                    existing.updated_at = datetime.now(tz=timezone.utc).astimezone()
                     existing.user_id = user_id
                     session.add(existing)
                 else:
                     logger.info(f"Creating new flow: {flow_id} with endpoint name {flow_endpoint_name}")
                     flow["user_id"] = user_id
                     flow = Flow.model_validate(flow, from_attributes=True)
-                    flow.updated_at = datetime.utcnow()
+                    flow.updated_at = datetime.now(tz=timezone.utc).astimezone()
                     session.add(flow)
 
 

src/backend/base/langflow/schema/message.py

@@ -29,7 +29,7 @@ def _timestamp_to_str(timestamp: datetime | str) -> str:
     if isinstance(timestamp, str):
         # Just check if the string is a valid datetime
         try:
-            datetime.strptime(timestamp, "%Y-%m-%d %H:%M:%S")
+            datetime.strptime(timestamp, "%Y-%m-%d %H:%M:%S")  # noqa: DTZ007
             return timestamp
         except ValueError as e:
             msg = f"Invalid timestamp: {timestamp}"

src/backend/base/langflow/services/database/service.py

@@ -2,7 +2,7 @@ from __future__ import annotations
 
 import time
 from contextlib import contextmanager
-from datetime import datetime
+from datetime import datetime, timezone
 from pathlib import Path
 from typing import TYPE_CHECKING
 
@@ -206,7 +206,7 @@ class DatabaseService(Service):
             logger.info(f"Running DB migrations in {self.script_location}")
 
             try:
-                buffer.write(f"{datetime.now().isoformat()}: Checking migrations\n")
+                buffer.write(f"{datetime.now(tz=timezone.utc).astimezone().isoformat()}: Checking migrations\n")
                 command.check(alembic_cfg)
             except Exception as exc:
                 if isinstance(exc, util.exc.CommandError | util.exc.AutogenerateDiffsDetected):
@@ -214,7 +214,7 @@ class DatabaseService(Service):
                     time.sleep(3)
 
             try:
-                buffer.write(f"{datetime.now().isoformat()}: Checking migrations\n")
+                buffer.write(f"{datetime.now(tz=timezone.utc).astimezone()}: Checking migrations\n")
                 command.check(alembic_cfg)
             except util.exc.AutogenerateDiffsDetected as exc:
                 logger.error(f"AutogenerateDiffsDetected: {exc}")

src/backend/base/langflow/services/tracing/langfuse.py

@@ -2,7 +2,7 @@ from __future__ import annotations
 
 import os
 from collections.abc import Sequence
-from datetime import datetime
+from datetime import datetime, timezone
 from typing import TYPE_CHECKING, Any
 from uuid import UUID
 
@@ -74,7 +74,7 @@ class LangFuseTracer(BaseTracer):
         metadata: dict[str, Any] | None = None,
         vertex: Vertex | None = None,
     ):
-        start_time = datetime.utcnow()
+        start_time = datetime.now(tz=timezone.utc)
         if not self._ready:
             return
 
@@ -103,7 +103,7 @@ class LangFuseTracer(BaseTracer):
         error: Exception | None = None,
         logs: Sequence[Log | dict] = (),
     ):
-        end_time = datetime.utcnow()
+        end_time = datetime.now(tz=timezone.utc)
         if not self._ready:
             return
 

src/backend/base/pyproject.toml

@@ -162,6 +162,7 @@ select = [
     "C4",
     "COM",
     "DJ",
+    "DTZ",
     "E",
     "EM",
     "F",