ui: minor refactoring

- Removed unused imports.
- Moved max gRPC channel settings to config.py

ui/bin/opensnitch-ui

@@ -23,11 +23,9 @@ from PyQt5 import QtWidgets, QtGui, QtCore
 
 import sys
 import os
-import time
 import signal
 import argparse
 import logging
-from threading import Timer
 
 from concurrent import futures
 
@@ -122,18 +120,7 @@ Examples:
 
             print("Using server address:", args.socket)
 
-            maxmsglencfg = cfg.getSettings(Config.DEFAULT_SERVER_MAX_MESSAGE_LENGTH)
-            if maxmsglencfg == '4MiB':
-                maxmsglen = 4194304
-            elif maxmsglencfg == '8MiB':
-                maxmsglen = 8388608
-            elif maxmsglencfg == '16MiB':
-                maxmsglen = 16777216
-            else:
-                maxmsglen = 4194304
-
-            print("gRPC Max Message Length:", maxmsglencfg)
-            print("                  Bytes:", maxmsglen)
+            maxmsglen = cfg.getMaxMsgLength()
 
             service = UIService(app, on_exit)
             # @doc: https://grpc.github.io/grpc/python/grpc.html#server-object
@@ -179,6 +166,5 @@ Examples:
 
     except KeyboardInterrupt:
         on_exit()
-
     finally:
         lockfile.unlock()

ui/opensnitch/config.py

@@ -223,3 +223,21 @@ class Config:
                 Config.RULES_DURATION_FILTER = []
         except Exception as e:
             print("setRulesDurationFilter() exception:", e)
+
+    def getMaxMsgLength(self):
+        """return maximum configured length for the gRPC channel.
+        Default size is 4MB, but in some scenarios it's not enough.
+        """
+        maxmsglen = 4194304
+        maxmsglencfg = self.getSettings(Config.DEFAULT_SERVER_MAX_MESSAGE_LENGTH)
+        if maxmsglencfg == '4MiB':
+            maxmsglen = 4194304
+        elif maxmsglencfg == '8MiB':
+            maxmsglen = 8388608
+        elif maxmsglencfg == '16MiB':
+            maxmsglen = 16777216
+
+        print("gRPC Max Message Length:", maxmsglencfg)
+        print("                  Bytes:", maxmsglen)
+
+        return maxmsglen