bug: strings not accepted in files param

[adriangb]

import requests
import httpx

# requests works
resp = requests.post("https://httpbin.org/post", files=[("name", "content")])
assert resp.status_code == 200
assert resp.json()["files"] == {"name": "content"}

# httpx fails, despite the signature of `files` saying it accepts a 2 tuple of (name: str, data: Union[str, bytes, file])
httpx.post("https://httpbin.org/post", files=[("name", "content")])   # raises a TypeError
assert resp.status_code == 200
assert resp.json()["files"] == {"name": "content"}

[tomchristie]

So... content there needs to be bytes - the annotation is derived from here... https://github.com/encode/httpx/blob/master/httpx/_types.py#L84-L93

FileContent = Union[IO[bytes], bytes]
FileTypes = Union[
    # file (or text)
    FileContent,
    # (filename, file (or text))
    Tuple[Optional[str], FileContent],
    # (filename, file (or text), content_type)
    Tuple[Optional[str], FileContent, Optional[str]],
]
RequestFiles = Union[Mapping[str, FileTypes], Sequence[Tuple[str, FileTypes]]]

Those comments look like they need updating tho'. They're not in line with what FileContent actually accepts.

We switched from accepting text-or-bytes to bytes-only here.
We could feasibly reconsider that, so that we only accept files-in-bytes-mode or bytes or text.

(We need to be able to know upfront how many bytes the content will be, and files opened in text mode don't allow us to do that, but text strings could be allowable, perhaps.)

[adriangb]

Hi Tom, thanks for the quick reply.

That makes sense. I may have been confused myself about the types (as per my comment above, for some reason I thought the type signature did accept str). I just opened #1898 to fix the comments.

Regarding the actual functionality, while it would be nice to be compatible w/ requests here, you must have already weighed the pros and cons in #1736 and friends, so I don't think I have anything to add there.

Either way, I'll close this because it's obvious that this is not a bug (beyond the comments being out of date), and a change to the functionality would be a feature request.