fix: rename incorrect keyword argument to parse_query_string

[dodumosu]

falconparser uses falcon.util.uri.parse_query_string, but uses
an incorrect keyword argument name, keep_blank_qs_values. the correct
argument name is keep_blank

see: #448

[lafrech]

Good.

I think it makes sense to maintain compatibility with Falcon 1. Flacon 2 is really recent and backward compat is cheap.

Please also add yourself to AUTHORS.

[lafrech]

Great. Just one typo to fix.

[lafrech]

One last change I didn't think of before.

Thanks.

[lafrech]

If we mean to support both Flacon 1 and 2, we should ensure the tests test both version. @dodumosu if you're not comfortable with modifying CI tests config, we'll do it when we get the time.

Is Flacon 1 still maintained? Shall we drop support for it in the next webargs major version ?

[Nateyo]

As far as I know, most of the development going on with falcon is now 2.0+. This PR should likely update the setup.py as well since right now it specifies falcon>=1.4.0,<2.0. There's actually another problem with args to req.stream.read() which I can submit a PR for, building on top of @dodumosu's changes

[lafrech]

What about keeping webargs 5.x Falcon 1.x and dropping Falcon 1.x in webargs 6.0?

webargs	Falcon
5	1 only
6	2 only

[lafrech]

@sloria, we could

• merge Only allow users to specify a single location per parse call & pass full location data to schema.load #420
• drop Python 2
• apply the change in this PR but just keep Flacon 2 compatibility, update setup.py (and CI config if needed)
• fix req.stream.read() as per this comment

We could publish beta releases along the way.

[sloria]

@lafrech I'm good with that plan

[lafrech]

Guys, I just merged #420.

You may rebase this and drop Falcon 1 (or start from scratch if it is easier), and send another PR to fix req.stream.read().

Thanks.

[lafrech]

Better wait until #454 is merged to avoid merge conflicts. Done.

[lafrech]

@dodumosu @Nateyo are you willing to tackle this?

No pressure, just asking. I could rebase the change in this PR when I get the time, but I don't know what @Nateyo has in mind regarding req.stream.read() and I don't use Falcon so ideally I'd rather defer that to you.

Basically, change setup.py to require falcon>=2 and do all required changes (the two expressed above + others if needed).

[Nateyo]

@lafrech Sure, I can work on it this week. I can cherry pick these commits and submit a whole new PR to the dev branch? Would that be easier since you want 5.x to keep Falcon 1 compat?

[lafrech]

Great. Thanks @Nateyo.

Further dev on webargs 5 will take place in branch 5.x-line. We're dropping Falcon 1 in dev branch. I wouldn't cherry-pick and just start from scratch as the changeset is much smaller when dropping Falcon 2 than when keeping compatibility. You may submit a single PR with the whole Falcon 2 move.

[lafrech]

Superseded by #459.