Content-Type is always set

[chrisseto]

As of 089e829 the Content-Type header is alway set if not otherwise set by the user.
This behavior is often undesirable and should be opt-in or at least provide an option to opt-out.
In the case of using Amazon S3's signed URLs, extra steps must be taken to have this header included.

[asvetlov]

When you send request you know content type, isn't it?

As an option we may add ignore_default_headers parameter for client API (both for ClientSession and request).

What's your use case? Why S3's signed URLs are not aware about content type?

[jettify]

As far as I remember issues with s3 is following: s3 api requires special signature to be added, when you preparing request. So you take body and headers then calculate signature, but content-type header is not present on that time, it will be added when you actually send request. For my botocore port I just added content-type explicitly https://github.com/jettify/aiobotocore/blob/master/aiobotocore/endpoint.py#L87-L98

[asvetlov]

Well, ignore_default_headers (maybe better name?) looks a good idea.

[chrisseto]

@jettify That would work but I'm not certain how that would affect amazon's own content type detection
@asvetlov I like the idea of ignore_default_headers but how far would that extend? Some that are automatically added are fairly helpful, ie User-Agent.

[jettify]

@chrisseto I tested my implementation with almost all tests (except pagination) of botocore library and it works as expected.

[asvetlov]

See also #379

[asvetlov]

@chrisseto we don't autoset User-Agent. But you may setup default user-agent header with ClientSession:

session = ClientSession(headers={'User-Agent': 'aiohttp client 0.17'})

[chrisseto]

Using aiohttp.request, on version 0.14.1, it seems to set it.

In [5]: aiohttp.__version__
Out[5]: '0.14.1'

In [6]: asyncio.get_event_loop().run_until_complete(aiohttp.request('GET', 'http://localhost:1234'))

~❯❯❯ nc -l 1234
GET / HTTP/1.1
ACCEPT: */*
ACCEPT-ENCODING: gzip, deflate
HOST: localhost:1234
CONTENT-LENGTH: 0
CONNECTION: keep-alive
USER-AGENT: Python/3.4 aiohttp/0.14.1

[asvetlov]

Ahh, got it. Sorry.

[mpaolini]

for User-Agent you can now use skip_auto_headers={'USER-AGENT'} and as of pull request #507 this same method works for Content-Type too

[mpaolini]

I think we can close this one

[lock]

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