Fix example loading issue (#10038)

* fix

* Add code

* add changeset

* Fix bug

* lint

* add changeset

* fix both cache examples=False,True

* format

---------

Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Abubakar Abid <abubakar@huggingface.co>

.changeset/real-words-listen.md

@@ -0,0 +1,5 @@
+---
+"gradio": patch
+---
+
+fix:Fix example loading issue

gradio/helpers.py

@@ -295,11 +295,25 @@ class Examples:
                 )
 
     def _get_processed_example(self, example):
+        """
+        This function is used to get the post-processed example values, ready to be used
+        in the frontend for each input component. For example, if the input components are
+        image components, the post-processed example values will be the a list of ImageData dictionaries
+        with the path, url, size, mime_type, orig_name, and is_stream keys. For any input components
+        that should be skipped (b/c they are None for all samples), they will simply be absent
+        from the returned list
+
+        Parameters:
+            example: a list of example values for each input component, excluding those components
+            that have all None values
+        """
         if example in self.non_none_processed_examples:
             return self.non_none_processed_examples[example]
         with utils.set_directory(self.working_directory):
             sub = []
-            for component, sample in zip(self.inputs, example, strict=False):
+            for component, sample in zip(
+                self.inputs_with_examples, example, strict=False
+            ):
                 prediction_value = component.postprocess(sample)
                 if isinstance(prediction_value, (GradioRootModel, GradioModel)):
                     prediction_value = prediction_value.model_dump()
@@ -309,9 +323,7 @@ class Examples:
                     postprocess=True,
                 )
                 sub.append(prediction_value)
-        return [
-            ex for (ex, keep) in zip(sub, self.input_has_examples, strict=False) if keep
-        ]
+        return sub
 
     def create(self) -> None:
         """Creates the Dataset component to hold the examples"""
@@ -332,7 +344,7 @@ class Examples:
                 self.cache_event = self.load_input_event = self.dataset.click(
                     load_example_with_output,
                     inputs=[self.dataset],
-                    outputs=self.inputs_with_examples + self.outputs,  # type: ignore
+                    outputs=self.inputs + self.outputs,  # type: ignore
                     show_progress="hidden",
                     postprocess=False,
                     queue=False,
@@ -360,7 +372,7 @@ class Examples:
                 self.load_input_event = self.dataset.click(
                     load_example,
                     inputs=[self.dataset],
-                    outputs=self.inputs_with_examples,  # type: ignore
+                    outputs=self.inputs_with_examples,
                     show_progress="hidden",
                     postprocess=False,
                     queue=False,
@@ -378,8 +390,8 @@ class Examples:
                         )
                     self.load_input_event.then(
                         self.fn,
-                        inputs=self.inputs,  # type: ignore
-                        outputs=self.outputs,  # type: ignore
+                        inputs=self.inputs,
+                        outputs=self.outputs,
                         show_api=False,
                     )
         else:
@@ -546,8 +558,8 @@ class Examples:
             _, fn_index = self.root_block.default_config.set_event_trigger(
                 [EventListenerMethod(Context.root_block, "load")],
                 fn=fn,
-                inputs=self.inputs_with_examples,  # type: ignore
-                outputs=self.outputs,  # type: ignore
+                inputs=self.inputs,
+                outputs=self.outputs,
                 preprocess=self.preprocess and not self._api_mode,
                 postprocess=self.postprocess and not self._api_mode,
                 batch=self.batch,
@@ -555,11 +567,13 @@ class Examples:
 
             if self.outputs is None:
                 raise ValueError("self.outputs is missing")
-            for i, example in enumerate(self.examples):
+            for i, example in enumerate(self.non_none_examples):
                 if example_id is not None and i != example_id:
                     continue
-                print(f"Caching example {i + 1}/{len(self.examples)}")
                 processed_input = self._get_processed_example(example)
+                for index, keep in enumerate(self.input_has_examples):
+                    if not keep:
+                        processed_input.insert(index, None)
                 if self.batch:
                     processed_input = [[value] for value in processed_input]
                 with utils.MatplotlibBackendMananger():

test/test_helpers.py

@@ -932,3 +932,35 @@ def test_check_event_data_in_cache():
                 },
             ),
         )
+
+
+def test_examples_no_cache_optional_inputs():
+    def foo(a, b, c, d):
+        return {"a": a, "b": b, "c": c, "d": d}
+
+    io = gr.Interface(
+        foo,
+        ["text", "text", "text", "text"],
+        "json",
+        cache_examples=False,
+        examples=[["a", "b", None, "d"], ["a", "b", None, "de"]],
+    )
+
+    try:
+        app, _, _ = io.launch(prevent_thread_lock=True)
+
+        client = TestClient(app)
+        with client as c:
+            for i in range(2):
+                response = c.post(
+                    f"{API_PREFIX}/run/predict/",
+                    json={
+                        "data": [i],
+                        "fn_index": 6,
+                        "trigger_id": 19,
+                        "session_hash": "test",
+                    },
+                )
+                assert response.status_code == 200
+    finally:
+        io.close()