fix(token_counter): address review comments by distinguishing URL fetch failures and adding type annotations

litellm/litellm_core_utils/token_counter.py

@@ -233,18 +233,20 @@ def get_image_dimensions(
         try:
             client: Final = _get_httpx_client()
             response: Final[httpx.Response] = safe_get(client, data)
+            response.raise_for_status()
             max_bytes: Final = int(MAX_IMAGE_URL_DOWNLOAD_SIZE_MB * 1024 * 1024)
             content_length: Final[str | None] = response.headers.get("Content-Length")
             if content_length is not None and int(content_length) > max_bytes:
-                pass  # skip download; img_data stays None
+                raise ValueError(f"Image at {data} exceeds maximum allowed size of {MAX_IMAGE_URL_DOWNLOAD_SIZE_MB}MB")
+            body: Final = response.read()
+            if len(body) <= max_bytes:
+                img_data = body
             else:
-                body: Final = response.read()
-                if len(body) <= max_bytes:
-                    img_data = body
-        except Exception:
-            pass
-    if img_data is None:
-        # Not a URL or fetch failed — assume base64
+                raise ValueError(f"Image at {data} exceeds maximum allowed size of {MAX_IMAGE_URL_DOWNLOAD_SIZE_MB}MB")
+        except Exception as e:
+            raise ValueError(f"Failed to fetch image from URL {data}: {e}") from e
+    else:
+        # Base64 string (with or without data URI header)
         if "," in data:
             _header, encoded = data.split(",", 1)
         else:

tests/unit/litellm_core_utils/test_token_counter.py

@@ -728,10 +728,10 @@ def test_get_image_dimensions_raw_base64():
     assert h == 1
 
 
-def test_get_image_dimensions_failed_url_raises_valueerror(monkeypatch):
+def test_get_image_dimensions_failed_url_raises_valueerror(monkeypatch: pytest.MonkeyPatch) -> None:
     from litellm.litellm_core_utils.token_counter import get_image_dimensions
 
-    def _failing_get(client, url, **kw):
+    def _failing_get(client: object, url: str, **kw: object) -> object:
         raise Exception("Connection timeout")
 
     monkeypatch.setattr(
@@ -739,7 +739,7 @@ def test_get_image_dimensions_failed_url_raises_valueerror(monkeypatch):
         _failing_get,
     )
 
-    with pytest.raises(ValueError, match="Unable to parse or decode image data"):
+    with pytest.raises(ValueError, match="Failed to fetch image from URL"):
         get_image_dimensions(data="https://unreachable-endpoint.com/test.png")