fix issues with calling async function from different threads that may or may not have an event loop

meshchat.py

@@ -23,6 +23,7 @@ from serial.tools import list_ports
 
 import database
 from src.backend.announce_handler import AnnounceHandler
+from src.backend.async_utils import AsyncUtils
 from src.backend.colour_utils import ColourUtils
 from src.backend.interface_config_parser import InterfaceConfigParser
 from src.backend.lxmf_message_fields import LxmfImageField, LxmfFileAttachmentsField, LxmfFileAttachment, LxmfAudioField
@@ -2408,7 +2409,7 @@ class ReticulumMeshChat:
         self.db_upsert_lxmf_message(lxmf_message)
 
         # send lxmf message state to all websocket clients
-        asyncio.run(self.websocket_broadcast(json.dumps({
+        AsyncUtils.run_async(self.websocket_broadcast(json.dumps({
             "type": "lxmf_message_state_updated",
             "lxmf_message": self.convert_lxmf_message_to_dict(lxmf_message),
         })))

src/backend/async_utils.py

@@ -0,0 +1,25 @@
+import asyncio
+
+
+class AsyncUtils:
+
+    # this method allows running the provided async coroutine from within a sync function
+    # it will run the async function on the existing event loop if available, otherwise it will start a new event loop
+    @staticmethod
+    def run_async(coroutine):
+
+        # attempt to get existing event loop
+        existing_event_loop = None
+        try:
+            existing_event_loop = asyncio.get_running_loop()
+        except RuntimeError:
+            # 'RuntimeError: no running event loop'
+            pass
+
+        # if there is an existing event loop running, submit the coroutine to that loop
+        if existing_event_loop and existing_event_loop.is_running():
+            existing_event_loop.create_task(coroutine)
+            return
+
+        # otherwise start a new event loop to run the coroutine
+        asyncio.run(coroutine)