Accept file-like objects as request data

[zacharyvoase]

I'd like it to be possible to pass in a file-like object as the source of request data, provided Content-Length and Content-Type headers have been specified already. Here's an example of what I'd like to do:

response = requests.put(
    'http://example.com/endpoint',
    data=open('filename', 'rb'),
    headers={
        "Content-Type": "text/plain",
        "Content-Length": os.stat('filename').st_size})

Alternatively, requests could even recognise that I've passed in a file object and perform an os.fstat(file_like_obj.fileno()) automatically.

Here's the bit of code that seems to be breaking:

https://github.com/kennethreitz/requests/blob/c7b99f78192bdff62fad4f92039396c0dfbe4fb8/requests/models.py#L267

When I pass in an object that is neither a string nor a dictionary, the call to dict() fails.

I'm able and willing to work on this in a fork, I just figured it would be better to submit it as an issue first.

[kennethreitz]

Interesting. I see no reason why we couldn't support that.

Supporting this everywhere would also force us to revisit the files parameter. Currently, it expects file-like objects. It should also accept bytes/unicode strings.

[zacharyvoase]

In this case, I'd imagine that the files parameter wouldn't even be used in Request.send(); by that point, the data could be put into one large file-like object with a computed Content-Length.