Update app.py

app.py

@@ -14,13 +14,16 @@ from backend.main import app as fastapi_app
 # Get base URLs from environment
 # Auto-detect HF Spaces environment
 FASTAPI_INTERNAL = "http://localhost:8000"  # Always use localhost for internal calls
-if os.getenv("SPACE_ID"):
-    # Running on HF Spaces - use the public Space URL for iframe/external access
+IS_HF_SPACES = bool(os.getenv("SPACE_ID"))
+if IS_HF_SPACES:
+    # Running on HF Spaces
+    # Use relative URLs for iframe (browser will resolve against current origin)
+    # This avoids CORS/auth issues with cross-origin requests
+    FASTAPI_URL = ""  # Empty = relative URLs like "/view/scene/welcome"
     space_host = os.getenv("SPACE_HOST", "")
-    FASTAPI_URL = f"https://{space_host}" if space_host else FASTAPI_INTERNAL
-    SPACE_URL = FASTAPI_URL
+    SPACE_URL = f"https://{space_host}" if space_host else ""
     print(f"🌐 HF Spaces detected: SPACE_ID={os.getenv('SPACE_ID')}, SPACE_HOST={space_host}")
-    print(f"   FASTAPI_URL (external)={FASTAPI_URL}")
+    print(f"   Using relative URLs for iframe")
     print(f"   FASTAPI_INTERNAL={FASTAPI_INTERNAL}")
 else:
     # Local development - FastAPI on 8000, Gradio on 7860
@@ -85,18 +88,20 @@ def wait_for_fastapi(max_retries=30, retry_interval=1):
     return False
 
 
-# Start FastAPI/MCP server in background
-def start_fastapi():
-    print("\n" + "="*60)
-    print("Starting FastAPI/MCP server on port 8000...")
-    print("="*60 + "\n")
-    uvicorn.run(fastapi_app, host="0.0.0.0", port=8000, log_level="info")
+# Start FastAPI/MCP server in background (only for local dev)
+# On HF Spaces, FastAPI will be mounted on Gradio's port
+if not IS_HF_SPACES:
+    def start_fastapi():
+        print("\n" + "="*60)
+        print("Starting FastAPI/MCP server on port 8000...")
+        print("="*60 + "\n")
+        uvicorn.run(fastapi_app, host="0.0.0.0", port=8000, log_level="info")
 
-fastapi_thread = threading.Thread(target=start_fastapi, daemon=True)
-fastapi_thread.start()
+    fastapi_thread = threading.Thread(target=start_fastapi, daemon=True)
+    fastapi_thread.start()
 
-# Wait for FastAPI to be ready
-wait_for_fastapi()
+    # Wait for FastAPI to be ready
+    wait_for_fastapi()
 
 
 def create_default_scene():
@@ -504,5 +509,14 @@ with gr.Blocks(
 if __name__ == "__main__":
     # Enable queue for handling multiple concurrent users (important for HF Spaces)
     demo.queue()
-    # Gradio 6: theme and css moved from gr.Blocks() to launch()
-    demo.launch(server_name="0.0.0.0", server_port=7860, theme=gr.themes.Soft(), css=APP_CSS)
+
+    if IS_HF_SPACES:
+        # On HF Spaces: Mount Gradio onto FastAPI so everything runs on port 7860
+        # This is required because HF Spaces only exposes one port
+        fastapi_app.mount("/", gr.mount_gradio_app(fastapi_app, demo, path="/", app_kwargs={"theme": gr.themes.Soft(), "css": APP_CSS}))
+        print("🚀 Starting combined FastAPI + Gradio on port 7860")
+        uvicorn.run(fastapi_app, host="0.0.0.0", port=7860, log_level="info")
+    else:
+        # Local dev: FastAPI already running on 8000, just launch Gradio on 7860
+        # Gradio 6: theme and css moved from gr.Blocks() to launch()
+        demo.launch(server_name="0.0.0.0", server_port=7860, theme=gr.themes.Soft(), css=APP_CSS)