Graphene-django: Don't know how to convert the Django class django_mysql.models.fields.json.JSONField

[quytang]

I've just added a JSONField on my models and graphene said Don't know how to convert the Django class django_mysql.models.fields.json.JSONField.
I think it wasn't supported yet but are there any way to work around?

thanks

[quytang]

I end up with this snippet, thanks

import graphene
from graphene_django.converter import convert_django_field
from django_mysql.models import JSONField

@convert_django_field.register(JSONField)
def convert_json_field_to_string(field, registry=None):
    return graphene.String()

[spockNinja]

That's definitely the way to go for a quick way to add your own fields that graphene-django doesn't support.

We would also welcome an addition like that to converter.py that does something similar to the postgres JSONField.

I will also note that we personally overrode the graphene type to be a graphene.GenericScalar, and then the JSON flows through and you do not have to re-parse it on the client side.

[denis-ryzhkov]

I you found this issue looking for postgres-JSONField like me, maybe this patch will help you:

• Description: Ask graphene_django to convert JSONField to GenericScalar (JSON as is) instead of default JSONString
• Code: https://gist.github.com/denis-ryzhkov/59efc5be73eebd099a66cd549226fba9

[cb109]

return graphene.GenericScalar() did not work for me, I had to import like from graphene.types.generic import GenericScalar and then return GenericScalar() instead. It is a great workaround, the JSON is passed through as expected, thanks!

[dopeboy]

Adding some more color to this in case there are others who arrive from google:

Suppose you have a django model like so:

from django.contrib.postgres.fields import JSONField

class Rapper(models.Model):
    name = models.CharField()
    bars = JSONField()

Here's what the Query object and connecting type would look like:

from graphene.types import generic
from graphene_django.types import DjangoObjectType

from .models import Rapper

class RapperType(DjangoObjectType):
    bars = generic.GenericScalar()

    class Meta:
        model = Rapper

And here's what a sample GraphQL query and response end up looking like:

{
  rapper {
    name
    bars
  }
}

{
  "data": {
    "rapper": {
      "name": "50 Cent",
      "bars": [
        "Joy wouldn't feel so good if it wasn't for pain",
        "It's your birthday"
      ]
    }
  }
}

[thongly]

@quytang and @spockNinja - Would it be helpful to add this to the docs? I can make a PR.

Also, an issue I've come across is that I'm having to register separately for each and every schema.py file where a query utilizes the custom type. I tried doing this at the the root schema.py, but it still errors out unless this is done at every single schema.py separately.