Enable External Event Loop Integration for ComfyUI [refactor] (#6114)

* Refactor main.py to support external event loop integration

* added optional "asyncio_loop" argument to allow using existing event loop

---------

Signed-off-by: bigcat88 <bigcat88@icloud.com>

main.py

@@ -150,9 +150,10 @@ def cuda_malloc_warning():
         if cuda_malloc_warning:
             logging.warning("\nWARNING: this card most likely does not support cuda-malloc, if you get \"CUDA error\" please run ComfyUI with: --disable-cuda-malloc\n")
 
-def prompt_worker(q, server):
+
+def prompt_worker(q, server_instance):
     current_time: float = 0.0
-    e = execution.PromptExecutor(server, lru_size=args.cache_lru)
+    e = execution.PromptExecutor(server_instance, lru_size=args.cache_lru)
     last_gc_collect = 0
     need_gc = False
     gc_collect_interval = 10.0
@@ -167,7 +168,7 @@ def prompt_worker(q, server):
             item, item_id = queue_item
             execution_start_time = time.perf_counter()
             prompt_id = item[1]
-            server.last_prompt_id = prompt_id
+            server_instance.last_prompt_id = prompt_id
 
             e.execute(item[2], prompt_id, item[3], item[4])
             need_gc = True
@@ -177,8 +178,8 @@ def prompt_worker(q, server):
                             status_str='success' if e.success else 'error',
                             completed=e.success,
                             messages=e.status_messages))
-            if server.client_id is not None:
-                server.send_sync("executing", { "node": None, "prompt_id": prompt_id }, server.client_id)
+            if server_instance.client_id is not None:
+                server_instance.send_sync("executing", {"node": None, "prompt_id": prompt_id}, server_instance.client_id)
 
             current_time = time.perf_counter()
             execution_time = current_time - execution_start_time
@@ -205,21 +206,23 @@ def prompt_worker(q, server):
                 last_gc_collect = current_time
                 need_gc = False
 
-async def run(server, address='', port=8188, verbose=True, call_on_start=None):
+
+async def run(server_instance, address='', port=8188, verbose=True, call_on_start=None):
     addresses = []
     for addr in address.split(","):
         addresses.append((addr, port))
-    await asyncio.gather(server.start_multi_address(addresses, call_on_start), server.publish_loop())
+    await asyncio.gather(server_instance.start_multi_address(addresses, call_on_start), server_instance.publish_loop())
 
 
-def hijack_progress(server):
+def hijack_progress(server_instance):
     def hook(value, total, preview_image):
         comfy.model_management.throw_exception_if_processing_interrupted()
-        progress = {"value": value, "max": total, "prompt_id": server.last_prompt_id, "node": server.last_node_id}
+        progress = {"value": value, "max": total, "prompt_id": server_instance.last_prompt_id, "node": server_instance.last_node_id}
 
-        server.send_sync("progress", progress, server.client_id)
+        server_instance.send_sync("progress", progress, server_instance.client_id)
         if preview_image is not None:
-            server.send_sync(BinaryEventTypes.UNENCODED_PREVIEW_IMAGE, preview_image, server.client_id)
+            server_instance.send_sync(BinaryEventTypes.UNENCODED_PREVIEW_IMAGE, preview_image, server_instance.client_id)
+
     comfy.utils.set_progress_bar_global_hook(hook)
 
 
@@ -229,7 +232,11 @@ def cleanup_temp():
         shutil.rmtree(temp_dir, ignore_errors=True)
 
 
-if __name__ == "__main__":
+def start_comfyui(asyncio_loop=None):
+    """
+    Starts the ComfyUI server using the provided asyncio event loop or creates a new one.
+    Returns the event loop, server instance, and a function to start the server asynchronously.
+    """
     if args.temp_directory:
         temp_dir = os.path.join(os.path.abspath(args.temp_directory), "temp")
         logging.info(f"Setting temp directory to: {temp_dir}")
@@ -243,19 +250,20 @@ def cleanup_temp():
         except:
             pass
 
-    loop = asyncio.new_event_loop()
-    asyncio.set_event_loop(loop)
-    server = server.PromptServer(loop)
-    q = execution.PromptQueue(server)
+    if not asyncio_loop:
+        asyncio_loop = asyncio.new_event_loop()
+        asyncio.set_event_loop(asyncio_loop)
+    prompt_server = server.PromptServer(asyncio_loop)
+    q = execution.PromptQueue(prompt_server)
 
     nodes.init_extra_nodes(init_custom_nodes=not args.disable_all_custom_nodes)
 
     cuda_malloc_warning()
 
-    server.add_routes()
-    hijack_progress(server)
+    prompt_server.add_routes()
+    hijack_progress(prompt_server)
 
-    threading.Thread(target=prompt_worker, daemon=True, args=(q, server,)).start()
+    threading.Thread(target=prompt_worker, daemon=True, args=(q, prompt_server,)).start()
 
     if args.quick_test_for_ci:
         exit(0)
@@ -272,9 +280,19 @@ def startup_server(scheme, address, port):
             webbrowser.open(f"{scheme}://{address}:{port}")
         call_on_start = startup_server
 
+    async def start_all():
+        await prompt_server.setup()
+        await run(prompt_server, address=args.listen, port=args.port, verbose=not args.dont_print_server, call_on_start=call_on_start)
+
+    # Returning these so that other code can integrate with the ComfyUI loop and server
+    return asyncio_loop, prompt_server, start_all
+
+
+if __name__ == "__main__":
+    # Running directly, just start ComfyUI.
+    event_loop, _, start_all_func = start_comfyui()
     try:
-        loop.run_until_complete(server.setup())
-        loop.run_until_complete(run(server, address=args.listen, port=args.port, verbose=not args.dont_print_server, call_on_start=call_on_start))
+        event_loop.run_until_complete(start_all_func())
     except KeyboardInterrupt:
         logging.info("\nStopped server")