fix encoding condition

src/huggingface_hub/inference/_common.py

@@ -286,10 +286,10 @@ def _prepare_payload(
 
     json: Dict[str, Any] = {}
     # If inputs is a bytes-like object, encode it to base64
-    if isinstance(inputs, (bytes, Path)) or (isinstance(inputs, str) and inputs.startswith(("http://", "https://"))):
-        json["inputs"] = _b64_encode(inputs)
-    # If inputs is a string or a dict, send it as is
-    elif isinstance(inputs, (dict, str)):
+    if expect_binary:
+        json["inputs"] = _b64_encode(inputs)  # type: ignore
+    # Otherwise (string, dict, list) send it as is
+    else:
         json["inputs"] = inputs
     # Add parameters to the json payload if any
     if has_parameters:

tests/test_inference_client.py

@@ -1173,7 +1173,17 @@ def test_resolve_chat_completion_url(
             None,
             "http://example.com",
         ),
-        # Case 10: inputs is a URL string with parameters
+        # Case 10: inputs is a URL string without parameters but expect_binary is False
+        (
+            "http://example.com",
+            None,
+            False,
+            {
+                "inputs": "http://example.com",
+            },
+            None,
+        ),
+        # Case 11: inputs is a URL string with parameters
         (
             "http://example.com",
             {"param1": "value1"},
@@ -1184,7 +1194,18 @@ def test_resolve_chat_completion_url(
             },
             None,
         ),
-        # Case 11: parameters contain None values
+        # Case 12: inputs is a URL string with parameters but expect_binary is False
+        (
+            "http://example.com",
+            {"param1": "value1"},
+            False,
+            {
+                "inputs": "http://example.com",
+                "parameters": {"param1": "value1"},
+            },
+            None,
+        ),
+        # Case 13: parameters contain None values
         (
             "simple text",
             {"param1": None, "param2": "value2"},