Retry ConnectError/ConnectTimeout happened in stream.start_tls

[Pliner]

Hi,

I am experiencing a small rare issue which has the following trace:

Traceback (most recent call last):
  File "/usr/local/lib/python3.11/site-packages/anyio/streams/tls.py", line 130, in _call_sslobject_method
    result = func(*args)
             ^^^^^^^^^^^
  File "/usr/local/lib/python3.11/ssl.py", line 979, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLSyscallError: Some I/O error occurred (_ssl.c:1002)

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.11/site-packages/httpcore/_exceptions.py", line 10, in map_exceptions
    yield
  File "/usr/local/lib/python3.11/site-packages/httpcore/backends/asyncio.py", line 78, in start_tls
    raise exc
  File "/usr/local/lib/python3.11/site-packages/httpcore/backends/asyncio.py", line 69, in start_tls
    ssl_stream = await anyio.streams.tls.TLSStream.wrap(
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/anyio/streams/tls.py", line 122, in wrap
    await wrapper._call_sslobject_method(ssl_object.do_handshake)
  File "/usr/local/lib/python3.11/site-packages/anyio/streams/tls.py", line 151, in _call_sslobject_method
    raise BrokenResourceError from exc
anyio.BrokenResourceError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.11/site-packages/httpx/_transports/default.py", line 60, in map_httpcore_exceptions
    yield
  File "/usr/local/lib/python3.11/site-packages/httpx/_transports/default.py", line 353, in handle_async_request
    resp = await self._pool.handle_async_request(req)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/httpcore/_async/connection_pool.py", line 253, in handle_async_request
    raise exc
  File "/usr/local/lib/python3.11/site-packages/httpcore/_async/connection_pool.py", line 237, in handle_async_request
    response = await connection.handle_async_request(request)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/httpcore/_async/connection.py", line 86, in handle_async_request
    raise exc
  File "/usr/local/lib/python3.11/site-packages/httpcore/_async/connection.py", line 63, in handle_async_request
    stream = await self._connect(request)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/httpcore/_async/connection.py", line 150, in _connect
    stream = await stream.start_tls(**kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/httpcore/backends/asyncio.py", line 66, in start_tls
    with map_exceptions(exc_map):
  File "/usr/local/lib/python3.11/contextlib.py", line 155, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/usr/local/lib/python3.11/site-packages/httpcore/_exceptions.py", line 14, in map_exceptions
    raise to_exc(exc)
httpcore.ConnectError

I have retries enabled on AsyncTransport, but ConnectError didn't attempt to retry at all if it was raised in stream.start_tls method.

It looks like that it is safe to retry such an error as well.

[Pliner]

Hi @tomchristie,

Sorry for bothering you, could you please review this PR?

Thanks!

[tomchristie]

Moving the start_tls inside the exception handling block looks correct to me, yup. Thanks.

[Pliner]

@tomchristie Thanks!

[Pliner]

@tomchristie Thanks for merging it. Could you please release it as 0.17.x?

[Pliner]

@tomchristie Thanks for merging it. Could you please release it as 0.17.x?

@tomchristie Sorry for bothering you again. Could you please release these changes?

[tomchristie]

@Pliner - Sure let's make that happen.
Would you like to attempt a release pull request with a minor version bump?
I can help guide you through the process.

[Pliner]

@tomchristie Sure, thanks. Let me look on a previous one(#661), then I will create a new one.

[Pliner]

#685