Create event loop manually if uvloop is available

asyncio.get_event_loop() does not call new_event_loop()
if current_thread() != main_thread()

freqtrade/rpc/api_server/uvicorn_threaded.py

@@ -8,12 +8,33 @@ import uvicorn
 class UvicornServer(uvicorn.Server):
     """
     Multithreaded server - as found in https://github.com/encode/uvicorn/issues/742
+
+    Removed install_signal_handlers() override based on changes from this commit:
+        https://github.com/encode/uvicorn/commit/ce2ef45a9109df8eae038c0ec323eb63d644cbc6
+
+    Cannot rely on asyncio.get_event_loop() to create new event loop because of this check:
+        https://github.com/python/cpython/blob/4d7f11e05731f67fd2c07ec2972c6cb9861d52be/Lib/asyncio/events.py#L638
+
+    Fix by overriding run() and forcing creation of new event loop if uvloop is available
     """
-    def install_signal_handlers(self):
+
+    def run(self, sockets=None):
+        import asyncio
+
         """
-        In the parent implementation, this starts the thread, therefore we must patch it away here.
+        Parent implementation calls self.config.setup_event_loop(),
+            but we need to create uvloop event loop manually
         """
-        pass
+        try:
+            import uvloop  # noqa
+        except ImportError:  # pragma: no cover
+            from uvicorn.loops.asyncio import asyncio_setup
+            asyncio_setup()
+        else:
+            asyncio.set_event_loop(uvloop.new_event_loop())
+
+        loop = asyncio.get_event_loop()
+        loop.run_until_complete(self.serve(sockets=sockets))
 
     @contextlib.contextmanager
     def run_in_thread(self):