reqparse raises on any non-JSON request with Werkzeug 2.1.0

[emosenkis]

Werkzeug 2.1.0 makes Request.get_json() raise if request is not JSON, which causes reqparse to raise when it attempts to access Request.json, which it does by default for all arguments without a specified location.

[gumptionthomas]

Confirmed. Additionally, setting location='args' did not prevent the exception from being raised.

[emosenkis]

Setting location='args' worked for me (I subclassed RequestParser to make the constructor use a custom Argument, which passes location='args' to super().__init__() when request.is_json is false).

[gumptionthomas]

@emosenkis That's a clever way to do that! However, after spending some hours investigating this I'm still unable to get the location='args' trick to work. And I'm just parsing a single string query arg (overkill to use the deprecated reqparse for this, I know).

As an aside, props to Github tox workflows that caught this for me (although I spent an hour assuming that I had broken something when I checked in some project documentation changes) ;-)

[hyper750]

As workaround downgrading to Werkzeug 2.0.3 does the trick.

[gumptionthomas]

I ended up moving to marshmallow for my query param parsing. It was very straight-forward. I'm still using Flask-RESTful for its Resource functionality.

[davidism]

It seems like Flask-Restful isn't actively maintained anymore according to #883, which lists alternatives, including Marshmallow in place of reqparse.

Flask-Restx seems to be based on the similar code, and has this PR open: python-restx/flask-restx#423. The same could be applied here.

Given that this isn't actively maintained, it's likely that other things will continue to diverge in incompatible ways. So if you're still using Flask-Restful, it's a very good idea to pin your dependency tree to avoid updates. Or migrate to the suggested alternatives (and still pin to control updates).

[jwoytek]

I've submitted a potential fix for this issue. FWIW, I also reported the issue at werkzeug (pallets/werkzeug#2339), as there may be other broken things, and it took me a bit to narrow down where the problem was.

[edit: I'm a dork and didn't get the link right for the issue]

[cainmagi]

Setting location='args' worked for me (I subclassed RequestParser to make the constructor use a custom Argument, which passes location='args' to super().__init__() when request.is_json is false).

It seems that letting location="values" also works.