AttributeError: 'NoneType' object has no attribute 'readuntil'

[ghost]

Hello,

I'm having trouble sending several emails in a loop. When I do so, I've got an error apparently spawning randomly. Do you have any ideas of what the issue is?

Please read the code below.

from time import sleep
import email
import asyncio
import aiosmtplib

loop = asyncio.get_event_loop()
for i in range(20):
    smtp = aiosmtplib.SMTP(hostname='gmail-smtp-in.l.google.com', port=25, loop=loop, use_tls=False)
    msg = email.message_from_string(my_eml)
    loop.run_until_complete(smtp.connect())
    loop.run_until_complete(smtp.starttls())
    loop.run_until_complete(smtp.send_message(msg))
    sleep(0.5)
    smtp.close()
loop.close()

Traceback (most recent call last):
  File "test.py", line 33, in <module>
    loop.run_until_complete(smtp.send_message(msg))
  File "/usr/local/Cellar/python/3.6.5/Frameworks/Python.framework/Versions/3.6/lib/python3.6/asyncio/base_events.py", line 468, in run_until_complete
    return future.result()
  File "/Users/myuser/.local/share/virtualenvs/proxy-D8_I7f06/lib/python3.6/site-packages/aiosmtplib/smtp.py", line 229, in send_message
    sender, recipients, flat_message, timeout=timeout)
  File "/Users/myuser/.local/share/virtualenvs/proxy-D8_I7f06/lib/python3.6/site-packages/aiosmtplib/smtp.py", line 155, in sendmail
    response = await self.data(message, timeout=timeout)
  File "/Users/myuser/.local/share/virtualenvs/proxy-D8_I7f06/lib/python3.6/site-packages/aiosmtplib/esmtp.py", line 278, in data
    timeout=timeout)
  File "/Users/myuser/.local/share/virtualenvs/proxy-D8_I7f06/lib/python3.6/site-packages/aiosmtplib/protocol.py", line 120, in read_response
    line = await self._readline(timeout=timeout)
  File "/Users/myuser/.local/share/virtualenvs/proxy-D8_I7f06/lib/python3.6/site-packages/aiosmtplib/protocol.py", line 227, in _readline
    self._stream_reader.readuntil(separator=b'\n'), loop=self._loop)
AttributeError: 'NoneType' object has no attribute 'readuntil'

Python 3.6.5
aiosmtplib 1.0.2

Cheers,
Taslim42.

[skillian]

Though I'm not positive about this, my first suspicion is it might have to do with starting and stopping the loop between every call. I would recommend first moving all of your code that uses the smtp object into an async function and then passing the invocation of that function into loop.run_until_complete(my_async_function(smtp))

[ghost]

Hello, thanks for your quick response.

I have the same result with this code.

async def test(smtp):
    for i in range(30):
        msg = email.message_from_string(my_eml)
        await smtp.send_message(msg)
        sleep(0.5)

loop = asyncio.get_event_loop()
smtp = aiosmtplib.SMTP(hostname='gmail-smtp-in.l.google.com', port=25, loop=loop, use_tls=False)
loop.run_until_complete(smtp.connect())
loop.run_until_complete(smtp.starttls())

loop.run_until_complete(test(smtp))
smtp.close()

Have you an idea ?

[cole]

I can't reproduce error so far (testing with smtp.gmail.com). It seems like the server is dropping the connection without sending a response, but that should raise SMTPServerDisconnected.

One quick thing, for STARTTLS connections, typically the port is 587, not 25.

[ghost]

Yes, the server is dropping the connection without sending a response. I encountered this issue only with gmail. So, I will catch AttributeError exception. Thank for your help.

[cole]

Going to reopen this as a reminder to myself to add a test case for it.

[cole]

Can't reproduce this still. Closing.