As an aiohttp client I use HTTP 1.1 pipelining when syncing from servers that support that

[bmbouter]

I'm confused, when aiohttp is the client does, it support this use case?

This suggests it did but was removed, but then given up on?

I also see mentions of it in the changelogs and older versions, but never in the client docs, only the server ones. If it doesn't support HTTP 1.1 pipelining it would help me if the docs would say that. I can open a PR if you want me to.

Any answer is ok, I just want to put my understanding on solid ground.

[aio-libs-bot]

GitMate.io thinks the contributor most likely able to help you is @asvetlov.

Possibly related issues are #6 (HTTP pipelining support improvements), #33 (HTTPS Support), #1290 (aiohttp 1.1), #863 (aiohttp support for http/2 protocol), and #505 (Client use aiohttp, will be hang up ,when server return 304).

[webknjaz]

Sorry, what is the question, again?

[asvetlov]

HTTP pipelining is the useless feature.
That is the real use case for pipelining except fancy benchmark numbers?

If you want to propose docs update -- you are welcome

[webknjaz]

@asvetlov I would argue that it's useful in terms of lowering TCP connection reestablishment overhead.

[asvetlov]

I would argue that the proper pipelining solution is HTTP/2 :)

[asvetlov]

BTW HTTP pipelining is about sending several HTTP requests without waiting for a response from the first one.
HTTP keepalive (supported by aiohttp from the very beginning) as about reusing the same connection without reopening TCP socket again and again.

[ra1u]

As some of you probably know, http pipelining is not new technology, but is in http 1.1 since year 1999 as per rfc2616 section-8.1.2.2 . It is required for server implementation that supports persistent connection (that is default).

I am trying to figure out how to use this with client.

It is not as simple as

for i in range(100):
  r = await (session.post('<url>',json=req))
  j = await (r.json())

because this is just thread of yield calls that can not be reordered by context manager.
so, maybe

for i in range(100):
  async with session.post('<url>',json=req) as r:
    j = await r.json()

should do the trick, but unfortunately it does not, because I am missing something and I am looking for some hint on why this does not work as expected.

[webknjaz]

@ra1u what exactly did you expect, though?

[webknjaz]

It is required for server implementation that supports persistent connection

why are you talking about the server while the conversation is about client-side?

Clients SHOULD NOT pipeline requests using non-idempotent methods

POST which you provide in your examples is not idemponent

[bmbouter]

Anyone want to review my tiny docs PR related to this? #3691