Passing array in query via axios

Hi,

I’m using axios to send a GET request to my flask-smorest endpoint. I know there’s no real agreement on this spec-wise, but the request’s querystring contains an array, and axios sends it in this format:

http://127.0.0.1:5000/api/v1/items/?types[]=cd&types[]=dvd

I’ve defined the schema used for reading the arguments as

class FilterSchema(ma.Schema):
    ...
    types = ma.fields.List(ma.fields.String(), missing=[])

Yet when I try to read the data received in my endpoint, types is empty:

@items_blp.route('/')
class ItemCollection(MethodView):
    @items_blp.arguments(FilterSchema(unknown=ma.EXCLUDE), location="query")
    @listings_blp.response(ItemSchema(many=True))
    def get(self, payload):
        # payload['types'] is empty...
        if payload['types']:
            qs = Item.objects.filter(item_type__in=payload['types'])
        return qs

Is this a missing feature in flask-smorest or should I ask on SO whether I should use another way to pass data?

[ThiefMaster]

Just FYI, you can configure axios to not do this [] nonsense that started in PHP when they thought it’d be even remotely a good idea to let the client decide whether unstructured form data should become an array or not…

Just pass paramsSerializer: params => qs.stringify(params, {arrayFormat: 'repeat'}) to your axios calls (or better: use axios.create() to create an instance where you pass this as a setting and use that instance everywhere)

[lafrech]

There’s two issues

• 1/ Parsing this query string format correctly.
• 2/ Documenting it correctly

1/ is a webargs issue, so I’ll transfer to webargs. You’ll have to write a custom parser (see https://webargs.readthedocs.io/en/latest/advanced.html#custom-parsers).

2/ is an apispec issue. I’m not sure there’s a way to write a spec that will display correctly in a frontend such as ReDoc or Swagger-UI, so you might end up just adding a generic comment at the beginning of the spec.