expose UNSET

[lepture]

Since UNSET is widely used in lots of functions' parameters. When people want to subclass and rewrite a method, or create a function to call httpx, they will need to use this UNSET to define their own parameters too.

A simple example:

def request_token(client, auth=UNSET, **kwargs):
    url = 'https://example.com/token'
    return client.get(url, auth=auth, **kwargs)

Here are some real examples:

1. https://github.com/lepture/authlib/blob/v0.15.2/authlib/integrations/httpx_client/oauth2_client.py#L117
2. https://github.com/lepture/authlib/blob/v0.15.2/authlib/integrations/httpx_client/oauth2_client.py#L136

[florimondmanca]

@lepture Hi,

I think it's an interesting point, and I don't think I have an answer right now. I do agree that having this specific type leak through is a bit of a smell, eventually. What would a world in which each library has its own UNSET type, to account for the fact that undefined doesn't exist in Python? 😅

But for now, for the specific use case of the two code examples you listed, it doesn't seem like we need to solve it just yet. In your 2 examples, and also in the snippet in this PR description, it doesn't struck me why the auth has to be exposed outside of **kwargs? There are no special operation performed on auth, it's just passed as self.post(..., auth=auth, **kwargs).

[florimondmanca]

Closing pre-emptively since I do agree on the problem (it's likely that UnsetType shouldn't leak to public methods), but exposing UNSET is not the right solution I believe. We can still discuss alternatives, though.

[lepture]

Yes, my given examples are not proper. Here is a proper one: https://github.com/lepture/authlib/blob/2af1b9f2c81d5cb847491e96cf762f69215fcf2d/authlib/integrations/httpx_client/oauth2_client.py#L84

There is a check if auth is defined, if not it should attach one.

[lepture]

And also, I have a suggestion, if there is a breaking change, please don’t release it with a bugfix version.

[florimondmanca]

Gotcha. ;-) Are you referring to a specific issue that's recently struck you?