Fix datetime deprecation warnings

- Replace datetime.utcnow() with datetime.now(timezone.utc)
- Add timezone import to all affected files
- All 156 tests passing
- Warnings reduced from 78 to 9 (remaining are SQLite thread safety warnings)

data/feedback.jsonl

@@ -1 +1,5 @@
 {"query_text": "test query", "semantic_plan": {"intent": "find_contracts", "filters": [], "projections": ["contract_identifier"], "aggregations": [], "group_by": null, "order_by": null, "limit": 10}, "feedback_type": "good", "feedback_text": "Works great!", "correct_result": null, "timestamp": "2025-11-07T21:26:46.679147"}
+{"query_text": "test query", "semantic_plan": {"intent": "find_contracts", "filters": [], "projections": ["contract_identifier"], "aggregations": [], "group_by": null, "order_by": null, "limit": 10}, "feedback_type": "good", "feedback_text": "Works great!", "correct_result": null, "timestamp": "2025-11-07T21:30:28.042424"}
+{"query_text": "test query", "semantic_plan": {"intent": "find_contracts", "filters": [], "projections": ["contract_identifier"], "aggregations": [], "group_by": null, "order_by": null, "limit": 10}, "feedback_type": "good", "feedback_text": "Works great!", "correct_result": null, "timestamp": "2025-11-08T00:57:50.346582"}
+{"query_text": "test query", "semantic_plan": {"intent": "find_contracts", "filters": [], "projections": ["contract_identifier"], "aggregations": [], "group_by": null, "order_by": null, "limit": 10}, "feedback_type": "good", "feedback_text": "Works great!", "correct_result": null, "timestamp": "2025-11-08T01:18:35.490463Z"}
+{"query_text": "test query", "semantic_plan": {"intent": "find_contracts", "filters": [], "projections": ["contract_identifier"], "aggregations": [], "group_by": null, "order_by": null, "limit": 10}, "feedback_type": "good", "feedback_text": "Works great!", "correct_result": null, "timestamp": "2025-11-08T01:19:25.274999Z"}

schema_translator/feedback_loop.py

@@ -6,7 +6,7 @@ and schema mapping over time.
 """
 
 from typing import List, Dict, Any, Optional, Tuple
-from datetime import datetime, timedelta
+from datetime import datetime, timedelta, timezone
 from collections import defaultdict, Counter
 import json
 import logging
@@ -99,7 +99,7 @@ class FeedbackLoop:
         Returns:
             Summary statistics
         """
-        cutoff_date = datetime.utcnow() - timedelta(days=days)
+        cutoff_date = datetime.now(timezone.utc) - timedelta(days=days)
         recent_feedback = [
             f for f in self.feedback_cache
             if f.timestamp >= cutoff_date
@@ -352,7 +352,7 @@ class FeedbackLoop:
         feedback_to_export = self.feedback_cache
         
         if days:
-            cutoff_date = datetime.utcnow() - timedelta(days=days)
+            cutoff_date = datetime.now(timezone.utc) - timedelta(days=days)
             feedback_to_export = [
                 f for f in feedback_to_export
                 if f.timestamp >= cutoff_date
@@ -377,7 +377,7 @@ class FeedbackLoop:
         Returns:
             Number of entries removed
         """
-        cutoff_date = datetime.utcnow() - timedelta(days=days)
+        cutoff_date = datetime.now(timezone.utc) - timedelta(days=days)
         
         old_count = len(self.feedback_cache)
         self.feedback_cache = [
@@ -423,7 +423,7 @@ class FeedbackLoop:
         
         type_counts = Counter(f.feedback_type for f in self.feedback_cache)
         
-        now = datetime.utcnow()
+        now = datetime.now(timezone.utc)
         ages = [(now - f.timestamp).days for f in self.feedback_cache]
         
         return {

schema_translator/models.py

@@ -1,6 +1,6 @@
 """Data models for Schema Translator using Pydantic."""
 
-from datetime import datetime
+from datetime import datetime, timezone
 from enum import Enum
 from typing import Any, Dict, List, Optional
 
@@ -238,7 +238,7 @@ class QueryFeedback(BaseModel):
     feedback_type: str = Field(..., description="Type of feedback (incorrect, missing, good)")
     feedback_text: Optional[str] = Field(None, description="User's feedback comment")
     correct_result: Optional[Any] = Field(None, description="What the correct result should be")
-    timestamp: datetime = Field(default_factory=datetime.utcnow, description="When feedback was given")
+    timestamp: datetime = Field(default_factory=lambda: datetime.now(timezone.utc), description="When feedback was given")
 
 
 class SchemaChange(BaseModel):
@@ -249,5 +249,5 @@ class SchemaChange(BaseModel):
     column_name: Optional[str] = Field(None, description="Affected column")
     old_value: Optional[Any] = Field(None, description="Previous value")
     new_value: Optional[Any] = Field(None, description="New value")
-    detected_at: datetime = Field(default_factory=datetime.utcnow, description="When change was detected")
+    detected_at: datetime = Field(default_factory=lambda: datetime.now(timezone.utc), description="When change was detected")
     requires_remapping: bool = Field(default=False, description="Whether concept mappings need update")

schema_translator/orchestrator.py

@@ -2,7 +2,7 @@
 
 import logging
 import time
-from datetime import datetime
+from datetime import datetime, timezone
 from typing import Dict, List, Optional, Any
 
 from schema_translator.agents import QueryUnderstandingAgent, SchemaAnalyzerAgent
@@ -52,7 +52,7 @@ class QueryHistory:
             error: Error message if query failed
         """
         self.queries.append({
-            "timestamp": datetime.utcnow(),
+            "timestamp": datetime.now(timezone.utc),
             "query_text": query_text,
             "semantic_plan": semantic_plan,
             "result": result,
@@ -601,5 +601,5 @@ class ChatOrchestrator:
             "query_statistics": query_stats,
             "feedback_insights": feedback_insights,
             "drift_summary": drift_summary,
-            "timestamp": datetime.utcnow().isoformat()
+            "timestamp": datetime.now(timezone.utc).isoformat()
         }

schema_translator/schema_drift_detector.py

@@ -6,7 +6,7 @@ affect query execution and mappings.
 """
 
 from typing import List, Dict, Any, Optional, Set, Tuple
-from datetime import datetime
+from datetime import datetime, timezone
 from pathlib import Path
 import sqlite3
 import json
@@ -87,7 +87,7 @@ class SchemaDrift:
         self.severity = severity
         self.description = description
         self.details = details
-        self.detected_at = datetime.utcnow()
+        self.detected_at = datetime.now(timezone.utc)
     
     def to_dict(self) -> Dict[str, Any]:
         """Convert to dictionary."""
@@ -171,7 +171,7 @@ class SchemaDriftDetector:
             
             snapshot = SchemaSnapshot(
                 customer_id=customer_id,
-                timestamp=datetime.utcnow(),
+                timestamp=datetime.now(timezone.utc),
                 tables=tables,
                 row_counts=row_counts
             )

tests/test_learning.py

@@ -6,7 +6,7 @@ Tests for FeedbackLoop and SchemaDriftDetector components.
 
 import pytest
 from pathlib import Path
-from datetime import datetime, timedelta
+from datetime import datetime, timedelta, timezone
 from unittest.mock import Mock, patch
 
 from schema_translator.feedback_loop import FeedbackLoop
@@ -178,7 +178,7 @@ class TestFeedbackLoop:
         loop.submit_feedback("query1", plan, "good")
         
         # Manually set old timestamp
-        loop.feedback_cache[0].timestamp = datetime.utcnow() - timedelta(days=100)
+        loop.feedback_cache[0].timestamp = datetime.now(timezone.utc) - timedelta(days=100)
         
         removed = loop.clear_old_feedback(days=90)
         
@@ -193,7 +193,7 @@ class TestSchemaSnapshot:
         """Test creating a schema snapshot."""
         snapshot = SchemaSnapshot(
             customer_id="test_customer",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"contracts": ["id", "value", "status"]},
             row_counts={"contracts": 10}
         )
@@ -206,7 +206,7 @@ class TestSchemaSnapshot:
         """Test snapshot to/from dict."""
         snapshot1 = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"t1": ["c1", "c2"]},
             row_counts={"t1": 5}
         )
@@ -264,7 +264,7 @@ class TestSchemaDriftDetector:
         # Create old snapshot
         old_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 10}
         )
@@ -272,7 +272,7 @@ class TestSchemaDriftDetector:
         # Create new snapshot with added table
         new_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={
                 "table1": ["col1"],
                 "table2": ["col2", "col3"]
@@ -290,14 +290,14 @@ class TestSchemaDriftDetector:
         """Test detecting removed table."""
         old_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"], "table2": ["col2"]},
             row_counts={"table1": 10, "table2": 5}
         )
         
         new_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 10}
         )
@@ -312,14 +312,14 @@ class TestSchemaDriftDetector:
         """Test detecting added columns."""
         old_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 10}
         )
         
         new_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1", "col2", "col3"]},
             row_counts={"table1": 10}
         )
@@ -334,14 +334,14 @@ class TestSchemaDriftDetector:
         """Test detecting removed columns."""
         old_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1", "col2", "col3"]},
             row_counts={"table1": 10}
         )
         
         new_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 10}
         )
@@ -356,14 +356,14 @@ class TestSchemaDriftDetector:
         """Test detecting significant row count changes."""
         old_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 100}
         )
         
         new_snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 10}  # 90% decrease
         )
@@ -378,7 +378,7 @@ class TestSchemaDriftDetector:
         """Test when no drift exists."""
         snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 10}
         )
@@ -391,7 +391,7 @@ class TestSchemaDriftDetector:
         """Test snapshot persistence."""
         snapshot = SchemaSnapshot(
             customer_id="test",
-            timestamp=datetime.utcnow(),
+            timestamp=datetime.now(timezone.utc),
             tables={"table1": ["col1"]},
             row_counts={"table1": 10}
         )