Update "Sending e-mail" docs to work with Python 3

The documentation for sending e-mails doesn’t seem to work when using Python 3. Also, I can’t seem to get e-mail sending working with Python 3 when sending binary (PDF) attachments. The code I’m using worked with Python 2. Details are below.

The Gmail REST API documentation for sending e-mail says to do the following:

raw = base64.urlsafe_b64encode(mime.as_string())
body = {'raw': raw}
messages = service.users().messages()
message = messages.send(userId='me', body=body).execute()

However, this code results in the following error:

File "/Users/chris/dev/.virtualenvs/my_package/lib/python3.4/base64.py", line 121, in urlsafe_b64encode
  return b64encode(s).translate(_urlsafe_encode_translation)
File "/Users/chris/dev/.virtualenvs/my_package/lib/python3.4/base64.py", line 62, in b64encode
  encoded = binascii.b2a_base64(s)[:-1]
TypeError: 'str' does not support the buffer interface

Changing as_string() in the above to as_bytes():

raw = base64.urlsafe_b64encode(mime.as_bytes())
body = {'raw': raw}
messages = service.users().messages()
message = messages.send(userId='me', body=body).execute()

results in the following error:

File "/Users/chris/dev/.virtualenvs/my_package/lib/python3.4/site-packages/googleapiclient/discovery.py", line 691, in method
  actual_path_params, actual_query_params, body_value)
File "/Users/chris/dev/.virtualenvs/my_package/lib/python3.4/site-packages/googleapiclient/model.py", line 149, in request
  body_value = self.serialize(body_value)
File "/Users/chris/dev/.virtualenvs/my_package/lib/python3.4/site-packages/googleapiclient/model.py", line 258, in serialize
  return json.dumps(body_value)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/json/__init__.py", line 230, in dumps
  return _default_encoder.encode(obj)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/json/encoder.py", line 192, in encode
  chunks = self.iterencode(o, _one_shot=True)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/json/encoder.py", line 250, in iterencode
  return _iterencode(o, 0)
File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/json/encoder.py", line 173, in default
  raise TypeError(repr(o) + " is not JSON serializable")
TypeError: b'Q29ud...TY9PS0tCg==' is not JSON serializable

If I add raw = raw.decode() to ensure that raw is a string in Python 3 as opposed to bytes, then the e-mail does get sent. However, the PDF attachment now seems to be corrupted:

raw = base64.urlsafe_b64encode(mime.as_bytes())
raw = raw.decode()
body = {'raw': raw}
messages = service.users().messages()
message = messages.send(userId='me', body=body).execute()

[divinedragon]

Just in case still faces an issue like me, here is my code.

with open(file, 'rb') as pdf_file:
      pdf = MIMEBase('application', "pdf")
      pdf.set_payload(pdf_file.read())
      encoders.encode_base64(pdf)
      pdf.add_header('Content-Disposition', 'attachment', filename=os.path.basename(file))

message.attach(pdf)

return {'raw': base64.urlsafe_b64encode(message.as_bytes()).decode()}

[ghost]

Still same issue in October 2017!

here is a full working python 3.6 script for sending messages with attatchments (you just need to fill out the arguments for create_message_with_attatchment):

https://pastebin.com/aCQaVavQ

I spent 2 hours to make it work, quite sad that they don’t update their documentation.