fix: correct image size limit enforcement and vertex_location None passthrough

token_counter.py: the previous size-limit raises were inside except Exception: pass,
so they were silently swallowed. The post-read raise was worse — img_data was already
assigned the full body before the raise, so the oversized value was used downstream.
Restructured to only assign img_data when the body is within bounds.

vertex_ai/common_utils.py and llm_passthrough_endpoints.py: the is-not-None guard
skipped validation for None, falling through to produce "https://None-aiplatform..."
Added explicit None check that raises before the regex guard.

litellm/litellm_core_utils/token_counter.py

@@ -219,10 +219,11 @@ def get_image_dimensions(
             max_bytes = int(MAX_IMAGE_URL_DOWNLOAD_SIZE_MB * 1024 * 1024)
             content_length = response.headers.get("Content-Length")
             if content_length is not None and int(content_length) > max_bytes:
-                raise ValueError("Image response exceeds size limit")
-            img_data = response.read()
-            if len(img_data) > max_bytes:
-                raise ValueError("Image response exceeds size limit")
+                pass  # skip download; img_data stays None
+            else:
+                body = response.read()
+                if len(body) <= max_bytes:
+                    img_data = body
         except Exception:
             pass
     if img_data is None:

litellm/llms/vertex_ai/common_utils.py

@@ -232,9 +232,9 @@ def get_vertex_base_url(
     """
     if vertex_location == "global":
         return "https://aiplatform.googleapis.com"
-    if vertex_location is not None and not re.match(
-        r"^[a-z][a-z0-9-]*$", vertex_location
-    ):
+    if vertex_location is None:
+        raise ValueError("vertex_location is required")
+    if not re.match(r"^[a-z][a-z0-9-]*$", vertex_location):
         raise ValueError("Invalid vertex_location format")
     return f"https://{vertex_location}-aiplatform.googleapis.com"
 

litellm/proxy/pass_through_endpoints/llm_passthrough_endpoints.py

@@ -1501,9 +1501,9 @@ def get_vertex_base_url(vertex_location: Optional[str]) -> str:
     """
     if vertex_location == "global":
         return "https://aiplatform.googleapis.com/"
-    if vertex_location is not None and not re.match(
-        r"^[a-z][a-z0-9-]*$", vertex_location
-    ):
+    if vertex_location is None:
+        raise ValueError("vertex_location is required")
+    if not re.match(r"^[a-z][a-z0-9-]*$", vertex_location):
         raise ValueError("Invalid vertex_location format")
     return f"https://{vertex_location}-aiplatform.googleapis.com/"