fix(logging): honor MAX_BASE64_LENGTH_FOR_LOGGING in error_information

Base64 data URIs echoed back by provider errors made error_information.error_message and its traceback grow to the size of the uploaded file, which then blew past the DB query size once written to LiteLLM_SpendLogs.metadata

litellm/litellm_core_utils/litellm_logging.py

@@ -69,7 +69,10 @@ from litellm.litellm_core_utils.get_litellm_params import get_litellm_params
 from litellm.litellm_core_utils.llm_cost_calc.tool_call_cost_tracking import (
     StandardBuiltInToolCostTracking,
 )
-from litellm.litellm_core_utils.logging_utils import truncate_base64_in_messages
+from litellm.litellm_core_utils.logging_utils import (
+    truncate_base64_data_uris,
+    truncate_base64_in_messages,
+)
 from litellm.litellm_core_utils.model_param_helper import ModelParamHelper
 from litellm.litellm_core_utils.redact_messages import (
     redact_message_input_output_from_custom_logger,
@@ -5014,8 +5017,8 @@ class StandardLoggingPayloadSetup:
             error_code=error_status,
             error_class=error_class,
             llm_provider=_llm_provider_in_exception,
-            traceback=traceback_info,
-            error_message=error_message,
+            traceback=truncate_base64_data_uris(traceback_info),
+            error_message=truncate_base64_data_uris(error_message),
             error_rate_limit_category=rate_limit_category,
             error_rate_limit_type=rate_limit_type,
             error_budget_entity_type=budget_error.entity_type if budget_error else None,

litellm/litellm_core_utils/logging_utils.py

@@ -68,7 +68,7 @@ def _base64_data_uri_replacer(match: re.Match) -> str:
     return f"data:{mime_type};base64,[base64_data truncated: {size_str}]"
 
 
-def _truncate_base64_in_string(value: str) -> str:
+def truncate_base64_data_uris(value: str) -> str:
     """Replace long base64 data-URI payloads in a string with a size placeholder."""
     if MAX_BASE64_LENGTH_FOR_LOGGING <= 0:
         return value
@@ -84,7 +84,7 @@ def _truncate_base64_in_value(value: Any) -> Any:
     # Stack entries: (source_value, depth, parent_container, key_or_index)
     # We mutate *copies* of dicts/lists in-place via parent references.
     if isinstance(value, str):
-        return _truncate_base64_in_string(value)
+        return truncate_base64_data_uris(value)
     if not isinstance(value, (dict, list)):
         return value
 
@@ -99,7 +99,7 @@ def _truncate_base64_in_value(value: Any) -> Any:
         if isinstance(container, dict):
             for k, v in container.items():
                 if isinstance(v, str):
-                    container[k] = _truncate_base64_in_string(v)
+                    container[k] = truncate_base64_data_uris(v)
                 elif isinstance(v, dict):
                     copy: Union[dict, list] = {ck: cv for ck, cv in v.items()}
                     container[k] = copy
@@ -111,7 +111,7 @@ def _truncate_base64_in_value(value: Any) -> Any:
         elif isinstance(container, list):
             for i, v in enumerate(container):
                 if isinstance(v, str):
-                    container[i] = _truncate_base64_in_string(v)
+                    container[i] = truncate_base64_data_uris(v)
                 elif isinstance(v, dict):
                     copy = {ck: cv for ck, cv in v.items()}
                     container[i] = copy

tests/test_litellm/litellm_core_utils/test_litellm_logging.py

@@ -2594,6 +2594,39 @@ def test_get_error_information_falls_back_to_str_when_no_message_attr():
     assert result["error_class"] == "ValueError"
 
 
+def test_get_error_information_truncates_base64_data_uris():
+    """
+    Regression for #34753: a failed request carrying a file upload echoed the
+    whole base64 payload back through the provider error string, so
+    error_information.error_message (and its traceback) grew to megabytes and
+    blew past the DB query size once written to LiteLLM_SpendLogs.metadata.
+
+    MAX_BASE64_LENGTH_FOR_LOGGING must bound base64 data URIs here too, while
+    keeping the surrounding human-readable error text intact.
+    """
+    from litellm.litellm_core_utils.litellm_logging import StandardLoggingPayloadSetup
+
+    payload = "A" * 3_000_000
+    message = (
+        "litellm.ContextWindowExceededError: OpenAIException - This model's maximum "
+        "context length is 128000 tokens. Request body: {'messages': [{'role': 'user', "
+        f"'content': [{{'type': 'file', 'file_data': 'data:application/pdf;base64,{payload}'}}]}}]}}"
+    )
+
+    exc = ValueError(message)
+    result = StandardLoggingPayloadSetup.get_error_information(
+        exc, traceback_str=f"Traceback: data:application/pdf;base64,{payload}"
+    )
+
+    assert payload not in result["error_message"]
+    assert payload not in (result["traceback"] or "")
+    assert len(result["error_message"]) < 1000
+    assert "base64_data truncated" in result["error_message"]
+    assert "base64_data truncated" in (result["traceback"] or "")
+    assert "maximum context length is 128000 tokens" in result["error_message"]
+    assert "data:application/pdf;base64," in result["error_message"]
+
+
 # ──────────────────────────────────────────────────────────────────────
 # Tests for _get_assembled_streaming_response non-streaming early return
 # ──────────────────────────────────────────────────────────────────────

tests/test_litellm/litellm_core_utils/test_logging_utils.py

@@ -6,7 +6,7 @@ import pytest
 
 from litellm.litellm_core_utils.logging_utils import (
     _format_base64_size,
-    _truncate_base64_in_string,
+    truncate_base64_data_uris,
     truncate_base64_in_messages,
 )
 
@@ -30,19 +30,19 @@ class TestFormatBase64Size:
 
 
 # ---------------------------------------------------------------------------
-# _truncate_base64_in_string
+# truncate_base64_data_uris
 # ---------------------------------------------------------------------------
 
 
 class TestTruncateBase64InString:
     def test_short_data_uri_not_truncated(self):
         uri = "data:image/png;base64,AAAA"
-        assert _truncate_base64_in_string(uri) == uri
+        assert truncate_base64_data_uris(uri) == uri
 
     def test_long_data_uri_truncated(self):
         payload = "A" * 200
         uri = f"data:application/pdf;base64,{payload}"
-        result = _truncate_base64_in_string(uri)
+        result = truncate_base64_data_uris(uri)
         assert "base64_data truncated" in result
         assert "application/pdf" in result
         assert payload not in result
@@ -50,12 +50,12 @@ class TestTruncateBase64InString:
     def test_multiple_data_uris(self):
         payload = "B" * 200
         text = f"first: data:image/png;base64,{payload} second: data:image/jpeg;base64,{payload}"
-        result = _truncate_base64_in_string(text)
+        result = truncate_base64_data_uris(text)
         assert result.count("base64_data truncated") == 2
 
     def test_no_data_uri(self):
         text = "hello world, no base64 here"
-        assert _truncate_base64_in_string(text) == text
+        assert truncate_base64_data_uris(text) == text
 
 
 # ---------------------------------------------------------------------------