improve non-ascii charset support in message body

Author: mikoim

email2slack.py

@@ -46,7 +46,11 @@ def parse(mime_mail):
     @staticmethod
     def extract_message(message):
         body = message.get_payload(decode=True)
-        return message['Content-Type'], body.decode(encoding=chardet.detect(body)['encoding'])
+        charset = chardet.detect(body)['encoding']
+        if charset is None:
+            charset = 'utf-8'
+
+        return message['Content-Type'], body.decode(encoding=charset)
 
     @staticmethod
     def parse_header(parsed_mail, field: str) -> str:

setup.py

@@ -10,7 +10,7 @@
 setup(
     name='email2slack',
 
-    version='1.0.0a2',
+    version='1.0.0a3',
 
     description='MIME E-mail forwarding script for Slack written in Python',
     long_description=long_description,