fix convert error when threshold is none (#780)

lyrebird/db/database_server.py

@@ -222,17 +222,21 @@ def get_page_count(self, channel_rules, page_size=20, search_str=''):
 
     def get_database_info(self):
         database_path = str(self.database_uri)
-        threshold_str = application._cm.config.get('event.file_size_threshold')
-        threshold_byte = convert_size_to_byte(threshold_str)
         size = self.database_uri.stat().st_size
         readable_size = convert_size(size)
-        oversized = threshold_byte and size > threshold_byte
         database_info = {
             'path': database_path,
-            'threshold': threshold_str,
             'size': readable_size,
-            'oversized': oversized
+            'oversized': False
         }
+
+        threshold_str = application._cm.config.get('event.file_size_threshold')
+        if threshold_str is not None:
+            threshold_byte = convert_size_to_byte(threshold_str)
+            oversized = threshold_byte and size > threshold_byte
+            database_info['threshold'] = threshold_str
+            database_info['oversized'] = oversized
+
         return database_info
 
     def reset(self):

lyrebird/utils.py

@@ -29,7 +29,7 @@ def convert_size(size_bytes):
     return "%s %s" % (s, size_name[i])
 
 
-def convert_size_to_byte(size_str):
+def convert_size_to_byte(size_str: str):
     size_str = size_str.strip().upper()
     match = re.match(r'^(\d+\.?\d*)\s*([KMGTPEZY]?[B])$', size_str)
     if not match: