subject encoding

[thomasgheberg]

There is a problem when the subject of an email contains a special character such as "°".
In this case, the subject is

'subject': <email.header.Header object at 0x7f799db1d6d0>

Traceback :

Traceback (most recent call last):
File "src/index_emails.py", line 231, in
IOLoop.instance().run_sync(load_from_file)
File "/usr/lib/python3/dist-packages/tornado/ioloop.py", line 576, in run_sync
return future_cell[0].result()
File "/usr/lib/python3/dist-packages/tornado/ioloop.py", line 547, in run
result = func()
File "src/index_emails.py", line 196, in load_from_file
upload_batch(upload_data)
File "src/index_emails.py", line 93, in upload_batch
upload_data_txt += json.dumps(item) + "\n"
File "/usr/lib/python3.8/json/init.py", line 231, in dumps
return _default_encoder.encode(obj)
File "/usr/lib/python3.8/json/encoder.py", line 199, in encode
chunks = self.iterencode(o, _one_shot=True)
File "/usr/lib/python3.8/json/encoder.py", line 257, in iterencode
return _iterencode(o, 0)
File "/usr/lib/python3.8/json/encoder.py", line 179, in default
raise TypeError(f'Object of type {o.class.name} '
TypeError: Object of type Header is not JSON serializable

Possible resolution in def convert_msg_to_json:

    if "subject" in result:
        result['subject'] = str(result['subject'])