Improved server_logic WebSocket Handling

Refined the server_logic function to better manage WebSocket disruptions:

- Integrated `handle_websocket_failure()` directly into `server_logic` to capture and inform about unexpected disconnection scenarios.
- Added conditionals to reset the `latest_image` when the WebSocket connection is deemed inactive.
- Ensured that the error handling mechanism is more resilient to abrupt connection terminations, especially in the context of receiving messages.

tsc_utils.py

@@ -524,7 +524,7 @@ import base64
 from io import BytesIO
 from torchvision import transforms
 
-latest_image = None
+latest_image = list()
 connected_client = None
 websocket_status = True
 
@@ -538,17 +538,26 @@ def handle_websocket_failure():
               f"preview is enabled and vae decoding is set to 'true`.")
 
 async def server_logic(websocket, path):
-    global latest_image, connected_client
+    global latest_image, connected_client, websocket_status
+
+    # If websocket_status is False, set latest_image to an empty list
+    if not websocket_status:
+        latest_image = list()
 
     # Assign the connected client
     connected_client = websocket
 
-    async for message in websocket:
-        # If not a command, treat it as image data
-        if not message.startswith('{'):
-            image_data = base64.b64decode(message.split(",")[1])
-            image = Image.open(BytesIO(image_data))
-            latest_image = pil2tensor(image)
+    try:
+        async for message in websocket:
+            # If not a command, treat it as image data
+            if not message.startswith('{'):
+                image_data = base64.b64decode(message.split(",")[1])
+                image = Image.open(BytesIO(image_data))
+                latest_image = pil2tensor(image)
+    except (websockets.exceptions.ConnectionClosedError, asyncio.exceptions.CancelledError):
+        handle_websocket_failure()
+    except Exception:
+        handle_websocket_failure()
 
 def run_server():
     loop = asyncio.new_event_loop()