"ConnectionResetError: Connection lost" occurs when disk space is 100% used.

[tvvister]

In case when space is not enough on the server side the stream.write operation fails with ConnectionResetError.
msg is like that 'Connection lost', and that's it, nothing is useful at all:

from aioftp import Client


async def main():
    client = Client()
    await client.connect(
        '0.0.0.0',
        port=21,
    )
    await client.login(
        user='',
        password='*',
    )
    try:
        stream = await client.upload_stream('test.txt', offset=0)
        await stream.write(b'data' * 1000)
    except ConnectionResetError:
        prepare_next_try()

Is there way to recognize that the problem is related to the shortage of volume rather than network issue?
If there is, then it would be helpful to make a stop of uploading instead of keep trying to reconnect endlessly.

Here is an example which shows something similar i suppose to have:

    try:
        stream = await client.upload_stream('test.txt', offset=0)
        await stream.write(b'data' * 1000)
    except ConnectionResetError:
        prepare_next_try()
    except NoSpaceError:
        stop_uploading()

[pohmelie]

Yes, it is possible, but should be implemented in 3 places:

• PathIO level
• Server level
• Client level
  There are some return codes, which represents such cases:

         452 Requested action not taken.
             Insufficient storage space in system.
         552 Requested file action aborted.
             Exceeded storage allocation (for current directory or
             dataset).

https://datatracker.ietf.org/doc/html/rfc959

If I will find a time for this I will implement this. Anyway 3rd person PR would be good.

[tvvister]

I've tried to check server response for popular ftp servers, which run from docker.

• garethflowers/ftp-server
• delfer/alpine-ftp-server

Both have broken pipeline without any excuse. I had only this:

BrokenPipeError(32, 'Broken pipe')

Nothing about error with codes 552 or 452. (upd.)

Also i found that the final exception will differ from time to time. I use 100Mb partition for ftp volume, and vary initial files' set and chunk size before start.

import aioftp
import asyncio

async def main():
    client = aioftp.Client()
    await client.connect("0.0.0.0")
    await client.login("user", "1234")

    async with client.upload_stream('/bytes1.txt') as out:
        while True:
            await out.write(b'0' * 65536) 
            # await out.write(b'0' * 25_000_000) # ~25Mb

There are two types of final exceptions:

• File "/home/user/.local/share/python3.10/lib/python3.10/asyncio/streams.py", line 167, in _drain_helper raise ConnectionResetError('Connection lost')
• File "/home/user/.local/share/python3.10/lib/python3.10/asyncio/selector_events.py", line 949, in _write_ready n = self._sock.send(self._buffer) BrokenPipeError: [Errno 32] Broken pipe

Could someone specify which impl of ftp server is full enough to handle disk full (452, 552 error codes) carefully?

updated: i found the way to adjust an ftp server to send me a response of 552 error code.