--conf option improvements (#1455)

* Conf file improvements
* Add test for loading config file

lbrynet/conf.py

@@ -49,6 +49,8 @@ DEFAULT_DHT_NODES = [
     ('lbrynet3.lbry.io', 4444)
 ]
 
+DEFAULT_SETTINGS_FILENAME = 'daemon_settings.yml'
+
 settings_decoders = {
     '.json': json.loads,
     '.yml': yaml.load
@@ -483,16 +485,15 @@ class Config:
             }
 
     def save_conf_file_settings(self):
-        if conf_file:
-            path = conf_file
-        else:
-            path = self.get_conf_filename()
+        path = conf_file or self.get_valid_settings_filename() or DEFAULT_SETTINGS_FILENAME
         # reverse the conversions done after loading the settings from the conf
         # file
         rev = self._convert_conf_file_lists_reverse(self._data[TYPE_PERSISTED])
         ext = os.path.splitext(path)[1]
         encoder = settings_encoders.get(ext, False)
-        assert encoder is not False, 'Unknown settings format %s' % ext
+        if not encoder:
+            raise ValueError('Unknown settings format: {}. Available formats: {}'
+                             .format(ext, list(settings_encoders.keys())))
         with open(path, 'w') as settings_file:
             settings_file.write(encoder(rev))
 
@@ -521,25 +522,25 @@ class Config:
         settings.node_id = settings.get_node_id()
 
     def load_conf_file_settings(self):
-        if conf_file:
-            path = conf_file
-        else:
-            path = self.get_conf_filename()
+        path = conf_file or self.get_valid_settings_filename()
+        self._read_conf_file(path)
+        # initialize members depending on config file
+        self.initialize_post_conf_load()
+
+    def _read_conf_file(self, path):
+        if not path:
+            return
         ext = os.path.splitext(path)[1]
         decoder = settings_decoders.get(ext, False)
-        assert decoder is not False, 'Unknown settings format %s' % ext
-        try:
+        if not decoder:
+            raise ValueError('Unknown settings format: {}. Available formats: {}'
+                             .format(ext, list(settings_decoders.keys())))
         with open(path, 'r') as settings_file:
             data = settings_file.read()
         decoded = self._fix_old_conf_file_settings(decoder(data))
         log.info('Loaded settings file: %s', path)
         self._validate_settings(decoded)
         self._data[TYPE_PERSISTED].update(self._convert_conf_file_lists(decoded))
-        except (IOError, OSError) as err:
-            log.info('%s: Failed to update settings from %s', err, path)
-
-        #initialize members depending on config file
-        self.initialize_post_conf_load()
 
     def _fix_old_conf_file_settings(self, settings_dict):
         if 'API_INTERFACE' in settings_dict:
@@ -590,7 +591,7 @@ class Config:
     def get_db_revision_filename(self):
         return os.path.join(self.ensure_data_dir(), self['DB_REVISION_FILE_NAME'])
 
-    def get_conf_filename(self):
+    def get_valid_settings_filename(self):
         data_dir = self.ensure_data_dir()
         yml_path = os.path.join(data_dir, 'daemon_settings.yml')
         json_path = os.path.join(data_dir, 'daemon_settings.json')
@@ -598,8 +599,6 @@ class Config:
             return yml_path
         elif os.path.isfile(json_path):
             return json_path
-        else:
-            return yml_path
 
     def get_installation_id(self):
         install_id_filename = os.path.join(self.ensure_data_dir(), "install_id")

tests/unit/test_conf.py

@@ -107,3 +107,16 @@ class SettingsTest(unittest.TestCase):
             conf_decoded_new = decoder(conf_entry_new)
             self.assertEqual(conf_decoded, conf_decoded_new)
 
+    def test_load_file(self):
+        settings = self.get_mock_config_instance()
+
+        # nonexistent file
+        conf.conf_file = 'monkey.yml'
+        with self.assertRaises(FileNotFoundError):
+            settings.load_conf_file_settings()
+
+        # invalid extensions
+        for filename in ('monkey.yymmll', 'monkey'):
+            conf.conf_file = filename
+            with self.assertRaises(ValueError):
+                settings.load_conf_file_settings()