Too little data for declared Content-Length

[ShivangKakkar]

EDIT:

After a lot of debugging, I found out that it actually happens if I use the same BinaryIO Object multiple times. Is it the usual way? Can't we use it again if we need it without file.close() or with context manager? If no, mind giving a brief explanation why it works like that?

OLD:

I get this error when I try to use post method on an external link (telegram bot api). I saw similar issue of 2019, but that was supposed to be fixed.

Please note that this issue occurs when, post is called more than once. First case is always successful but later ones give this error.

Traceback

Traceback (most recent call last):
    resp = await req.post(url=add_to_pack_url, params=params, files=files)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1820, in post
    return await self.request(
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1506, in request
    return await self.send(request, auth=auth, follow_redirects=follow_redirects)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1593, in send
    response = await self._send_handling_auth(
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1621, in _send_handling_auth
    response = await self._send_handling_redirects(
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1658, in _send_handling_redirects
    response = await self._send_single_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1695, in _send_single_request
    response = await transport.handle_async_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_transports\default.py", line 353, in handle_async_request
    resp = await self._pool.handle_async_request(req)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\connection_pool.py", line 244, in handle_async_request
    raise exc
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\connection_pool.py", line 228, in handle_async_request
    response = await connection.handle_async_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\connection.py", line 90, in handle_async_request
    return await self._connection.handle_async_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 102, in handle_async_request
    raise exc
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 72, in handle_async_request
    await self._send_request_body(**kwargs)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 128, in _send_request_body
    await self._send_event(event, timeout=timeout)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 131, in _send_event
    bytes_to_send = self._h11_state.send(event)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_connection.py", line 468, in send
    data_list = self.send_with_data_passthrough(event)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_connection.py", line 501, in send_with_data_passthrough
    writer(event, data_list.append)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_writers.py", line 60, in __call__
    self.send_eom(event.headers, write)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_writers.py", line 83, in send_eom
    raise LocalProtocolError("Too little data for declared Content-Length")
h11._util.LocalProtocolError: Too little data for declared Content-Length

[tomchristie]

After a lot of debugging, I found out that it actually happens if I use the same BinaryIO Object multiple times. Is it the usual way? Can't we use it again if we need it without file.close() or with context manager? If no, mind giving a brief explanation why it works like that?

Okey dokes - let's see if we can make some user experience improvements here.

Can you provide an absolutely-minimal-as-possible example that replicates this, so we can talk it through? (You can use https://httpbin.org/post if you need a public URL for the purposes of demonstrating it)

[ShivangKakkar]

Okey dokes - let's see if we can make some user experience improvements here.

Can you provide an absolutely-minimal-as-possible example that replicates this, so we can talk it through? (You can use https://httpbin.org/post if you need a public URL for the purposes of demonstrating it)

Thanks for the reply. Here's a minimal example that exactly replicates this.

Code

import httpx
import asyncio


async def main():
    client = httpx.AsyncClient()
    data = {
        'id': 0
    }
    files = {'files': open("img.png", 'rb')}
    req = await client.post(url="https://httpbin.org/post", data=data, files=files)
    print(req)
    req = await client.post(url="https://httpbin.org/post", data=data, files=files)
    print(req)
    await client.aclose()

asyncio.run(main())

I used a random image for testing

Traceback

Traceback (most recent call last):
  File "D:\Tests\httpx-tests\main.py", line 18, in <module>
    asyncio.run(main())
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\asyncio\runners.py", line 44, in run
    return loop.run_until_complete(main)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\asyncio\base_events.py", line 641, in run_until_complete
    return future.result()
  File "D:\Tests\httpx-tests\main.py", line 13, in main
    req = await client.post(url="https://httpbin.org/post", data=data, files=files)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1820, in post
    return await self.request(
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1506, in request
    return await self.send(request, auth=auth, follow_redirects=follow_redirects)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1593, in send
    response = await self._send_handling_auth(
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1621, in _send_handling_auth
    response = await self._send_handling_redirects(
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1658, in _send_handling_redirects
    response = await self._send_single_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_client.py", line 1695, in _send_single_request
    response = await transport.handle_async_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpx\_transports\default.py", line 353, in handle_async_request
    resp = await self._pool.handle_async_request(req)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\connection_pool.py", line 244, in handle_async_request
    raise exc
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\connection_pool.py", line 228, in handle_async_request
    response = await connection.handle_async_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\connection.py", line 90, in handle_async_request
    return await self._connection.handle_async_request(request)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 102, in handle_async_request
    raise exc
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 72, in handle_async_request
    await self._send_request_body(**kwargs)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 128, in _send_request_body
    await self._send_event(event, timeout=timeout)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\httpcore\_async\http11.py", line 131, in _send_event
    bytes_to_send = self._h11_state.send(event)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_connection.py", line 468, in send
    data_list = self.send_with_data_passthrough(event)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_connection.py", line 501, in send_with_data_passthrough
    writer(event, data_list.append)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_writers.py", line 60, in __call__
    self.send_eom(event.headers, write)
  File "C:\Users\Stark\AppData\Local\Programs\Python\Python310\lib\site-packages\h11\_writers.py", line 83, in send_eom
    raise LocalProtocolError("Too little data for declared Content-Length")
h11._util.LocalProtocolError: Too little data for declared Content-Length

Note: The error isn't raised if the file is closed and reopened before any other [2nd to n] request.

[tomchristie]

Confirmed this as a bug and resolved in #2065

Thanks for reporting this. That pull request needs a maintainer review before it can go in.

We can either wait for someone already on @encode/maintainers to handle that, or else I can invite you as a maintainer, and you can double check for yourself if the fix works for you and then approve the PR if so. Any preference?

[ShivangKakkar]

Thanks for considering me. I believe I could review it but someone else has already approved it so there seems no need.