Fix issues 3

services/training/app/services/training_service.py

@@ -6,7 +6,8 @@ Main training service that uses the repository pattern for data access
 from typing import Dict, List, Any, Optional
 import uuid
 import structlog
-from datetime import datetime
+from datetime import datetime, date, timezone
+from decimal import Decimal
 from sqlalchemy.ext.asyncio import AsyncSession
 import json
 import numpy as np
@@ -37,10 +38,26 @@ logger = structlog.get_logger()
 
 def make_json_serializable(obj):
     """Convert numpy/pandas types, datetime, and UUID objects to JSON-serializable Python types"""
-    import uuid
-    from decimal import Decimal
-    from datetime import datetime, date
     
+    # Handle None values
+    if obj is None:
+        return None
+    
+    # Handle basic datetime types first (most common)
+    if isinstance(obj, datetime):
+        return obj.isoformat()
+    elif isinstance(obj, date):
+        return obj.isoformat()
+    
+    # Handle pandas timestamp types
+    if hasattr(pd, 'Timestamp') and isinstance(obj, pd.Timestamp):
+        return obj.isoformat()
+    
+    # Handle numpy datetime types
+    if hasattr(np, 'datetime64') and isinstance(obj, np.datetime64):
+        return pd.Timestamp(obj).isoformat()
+    
+    # Handle numeric types
     if isinstance(obj, (np.integer, pd.Int64Dtype)):
         return int(obj)
     elif isinstance(obj, (np.floating, pd.Float64Dtype)):
@@ -51,19 +68,36 @@ def make_json_serializable(obj):
         return obj.tolist()
     elif isinstance(obj, pd.DataFrame):
         return obj.to_dict('records')
+    elif isinstance(obj, Decimal):
+        return float(obj)
+    
+    # Handle UUID types
     elif isinstance(obj, uuid.UUID):
         return str(obj)
     elif hasattr(obj, '__class__') and 'UUID' in str(obj.__class__):
         # Handle any UUID-like objects (including asyncpg.pgproto.pgproto.UUID)
         return str(obj)
-    elif isinstance(obj, Decimal):
-        return float(obj)
+    
+    # Handle collections recursively
     elif isinstance(obj, dict):
         return {k: make_json_serializable(v) for k, v in obj.items()}
-    elif isinstance(obj, list):
+    elif isinstance(obj, (list, tuple)):
         return [make_json_serializable(item) for item in obj]
-    else:
+    elif isinstance(obj, set):
+        return [make_json_serializable(item) for item in obj]
+    
+    # Handle other common types
+    elif isinstance(obj, (str, int, float, bool)):
         return obj
+    
+    # Last resort: try to convert to string
+    else:
+        try:
+            # For any other object, try to convert to string
+            return str(obj)
+        except Exception:
+            # If all else fails, return None
+            return None
 
 
 class EnhancedTrainingService: