feat(litellm_logging.py): refactor standard_logging_payload function … (#6388)

* feat(litellm_logging.py): refactor standard_logging_payload function to be <50 LOC

fixes issue where usage information was not following typed values

* fix(litellm_logging.py): fix completion start time handling

tests/logging_callback_tests/test_standard_logging_payload.py

@@ -0,0 +1,67 @@
+"""
+Unit tests for StandardLoggingPayloadSetup
+"""
+
+import json
+import os
+import sys
+from datetime import datetime
+from unittest.mock import AsyncMock
+
+from pydantic.main import Model
+
+sys.path.insert(
+    0, os.path.abspath("../..")
+)  # Adds the parent directory to the system-path
+
+import pytest
+import litellm
+from litellm.types.utils import Usage
+from litellm.litellm_core_utils.litellm_logging import StandardLoggingPayloadSetup
+
+
+@pytest.mark.parametrize(
+    "response_obj,expected_values",
+    [
+        # Test None input
+        (None, (0, 0, 0)),
+        # Test empty dict
+        ({}, (0, 0, 0)),
+        # Test valid usage dict
+        (
+            {
+                "usage": {
+                    "prompt_tokens": 10,
+                    "completion_tokens": 20,
+                    "total_tokens": 30,
+                }
+            },
+            (10, 20, 30),
+        ),
+        # Test with litellm.Usage object
+        (
+            {"usage": Usage(prompt_tokens=15, completion_tokens=25, total_tokens=40)},
+            (15, 25, 40),
+        ),
+        # Test invalid usage type
+        ({"usage": "invalid"}, (0, 0, 0)),
+        # Test None usage
+        ({"usage": None}, (0, 0, 0)),
+    ],
+)
+def test_get_usage(response_obj, expected_values):
+    """
+    Make sure values returned from get_usage are always integers
+    """
+
+    usage = StandardLoggingPayloadSetup.get_usage_from_response_obj(response_obj)
+
+    # Check types
+    assert isinstance(usage.prompt_tokens, int)
+    assert isinstance(usage.completion_tokens, int)
+    assert isinstance(usage.total_tokens, int)
+
+    # Check values
+    assert usage.prompt_tokens == expected_values[0]
+    assert usage.completion_tokens == expected_values[1]
+    assert usage.total_tokens == expected_values[2]