implement restart behavior

logprep/util/http.py

@@ -55,6 +55,7 @@ def __init__(
 
         if (
             hasattr(self, "thread")
+            and self.thread is not None
             and self.thread.is_alive()  # pylint: disable=access-member-before-definition
         ):
             self.shut_down()
@@ -70,17 +71,21 @@ def __init__(
         logprep_log_config = json.loads(
             os.environ.get("LOGPREP_LOG_CONFIG", json.dumps(DEFAULT_LOG_CONFIG))
         )
-        uvicorn_config = uvicorn.Config(**uvicorn_config, app=app, log_config=logprep_log_config)
+        self.uvicorn_config = uvicorn.Config(
+            **uvicorn_config, app=app, log_config=logprep_log_config
+        )
         logging.getLogger("uvicorn.access").name = self._logger_name
         logging.getLogger("uvicorn.error").name = self._logger_name
-        self.server = uvicorn.Server(uvicorn_config)
-        self.thread = threading.Thread(daemon=daemon, target=self.server.run)
+        self.server = None
+        self.thread = None
+        self.daemon = daemon
 
     def start(self):
         """Collect all configs, initiate application server and webserver
         and run thread with uvicorn+falcon http server and wait
         until it is up (started)"""
-
+        self.server = uvicorn.Server(self.uvicorn_config)
+        self.thread = threading.Thread(daemon=self.daemon, target=self.server.run)
         self.thread.start()
         while not self.server.started:
             continue
@@ -95,3 +100,11 @@ def shut_down(self):
             self._logger.debug("Wait for server to exit gracefully...")
             continue
         self.thread.join()
+        self.server = None
+        self.thread = None
+
+    def restart(self):
+        """Restart the server by shutting down the existing server and
+        starting a new one"""
+        self.shut_down()
+        self.start()