test the init_logging_system() method

app/src/server.py

@@ -26,6 +26,12 @@ class Server():
     serv_name = ''
     version = ''
     src_dir = ''
+
+    ####
+    # The following default values are used for the unit tests only, since
+    # `Server.parse_args()' will not be called during test setup.
+    # Ofcorse, we can call `Server.parse_args()' in a test case explicitly
+    # to overwrite this values
     config_path = './config/'
     json_config = ''
     toml_config = ''
@@ -86,8 +92,7 @@ class Server():
         self.log_path = args.log_path
         self.log_backups = args.log_backups
 
-    def init_logging_system(self):   # pragma: no cover
-
+    def init_logging_system(self):
         setattr(logging.handlers, "log_path", self.log_path)
         setattr(logging.handlers, "log_backups", self.log_backups)
         os.makedirs(self.log_path, exist_ok=True)

app/tests/test_server.py

@@ -91,6 +91,34 @@ class TestServerClass:
             s.parse_args(['--inalid', '/tmp/my-config'])
         assert exc_info.value.code == 2
 
+    def test_init_logging_system(self):
+        s = self.FakeServer()
+        s.src_dir = 'app/src/'
+        s.init_logging_system()
+        assert s.log_backups == 0
+        assert s.log_level == None
+        assert logging.handlers.log_path == './log/'
+        assert logging.handlers.log_backups == 0
+        assert logging.getLogger().level == logging.DEBUG
+        assert logging.getLogger('msg').level == logging.DEBUG
+        assert logging.getLogger('conn').level == logging.DEBUG
+        assert logging.getLogger('data').level == logging.DEBUG
+        assert logging.getLogger('tracer').level == logging.INFO
+        assert logging.getLogger('asyncio').level == logging.INFO
+
+        os.environ["LOG_LVL"] = "WARN"
+        s.parse_args(['--log_backups', '3'])
+        s.init_logging_system()
+        assert s.log_backups == 3
+        assert s.log_level == logging.WARNING
+        assert logging.handlers.log_backups == 3
+        assert logging.getLogger().level == s.log_level
+        assert logging.getLogger('msg').level == s.log_level
+        assert logging.getLogger('conn').level == s.log_level
+        assert logging.getLogger('data').level == s.log_level
+        assert logging.getLogger('tracer').level == s.log_level
+        assert logging.getLogger('asyncio').level == s.log_level
+
 
 class TestApp:
     @pytest.mark.asyncio