Fix: Replace streaming with chained events to resolve ProtocolError

app.py

@@ -239,15 +239,14 @@ def generate_table_html(rows):
     </div>
     """
 
+def show_loader():
+    return LOADER_HTML
+
 def run_benchmark(query):
     print(f"DEBUG: Starting benchmark for query: {query}")
     
-    # 1. Yield Loader
-    yield LOADER_HTML
-    time.sleep(0.2) # Ensure loader renders before heavy processing
-    
     try:
-        # 2. Perform Search (Live)
+        # Perform Search (Live)
         start_total = time.time()
         
         # Generate Embedding
@@ -272,7 +271,7 @@ def run_benchmark(query):
         end_total = time.time()
         latency_ms = (end_total - start_total) * 1000
         
-        # 3. Construct Data Rows
+        # Construct Data Rows
         
         # Live Row (MiniLM + LightGBM)
         # Mocking shards searched based on confidence for demo visual
@@ -320,17 +319,16 @@ def run_benchmark(query):
         
         all_rows = [live_row] + ref_rows
         
-        print("DEBUG: Yielding final HTML.")
-        # 4. Yield Final HTML
-        yield generate_table_html(all_rows)
+        print("DEBUG: Returning final HTML.")
+        return generate_table_html(all_rows)
 
     except Exception as e:
         import traceback
         error_msg = traceback.format_exc()
         print(f"CRITICAL ERROR in run_benchmark: {error_msg}")
         
-        # Yield Error HTML
-        yield f"""
+        # Return Error HTML
+        return f"""
         <div class="bg-red-50 border border-red-200 rounded-2xl p-6 text-red-800">
             <h3 class="font-bold text-lg mb-2 flex items-center gap-2">
                 <span class="material-symbols-outlined">error</span>
@@ -373,10 +371,29 @@ with gr.Blocks(theme=gr.themes.Base(), css=None, head=HEAD_HTML) as demo:
         # Footer Info
         gr.HTML(FOOTER_INFO_HTML)
 
-    # Interactions
-    submit_btn.click(run_benchmark, inputs=[query_input], outputs=[results_area])
-    query_input.submit(run_benchmark, inputs=[query_input], outputs=[results_area])
+    # Interactions: Chained Events
+    # 1. Show Loader immediately
+    # 2. Run Benchmark and show results
+    
+    submit_btn.click(
+        show_loader, 
+        inputs=None, 
+        outputs=[results_area]
+    ).then(
+        run_benchmark, 
+        inputs=[query_input], 
+        outputs=[results_area]
+    )
+    
+    query_input.submit(
+        show_loader, 
+        inputs=None, 
+        outputs=[results_area]
+    ).then(
+        run_benchmark, 
+        inputs=[query_input], 
+        outputs=[results_area]
+    )
 
 if __name__ == "__main__":
-    # Disable queue to prevent h11 LocalProtocolError on HF Spaces
-    demo.launch()
+    demo.queue().launch()