Support for GIS field types

Right now, using a DjangoObjectType on a model that contains GIS fields (like django.contrib.gis.db.models.fields.PointField) will trigger an exception: Exception: Don't know how to convert the Django field myapp.MyModel.point (<class 'django.contrib.gis.db.models.fields.PointField'>).

It would be great to add support for this. Otherwise, is there any docs on how to create a custom Field with custom serialization/deserialization like in django-rest-framework?

[mongkok]

Hi @sanfilippopablo,

the PR convert Geometry fields to well-known text (WKT):

{
    "id": "1",
    "location": "SRID=4326;POINT (0 1)"
}

if you want to convert to GeoJSON:

import json

from django.contrib.gis.db import models

import graphene
from graphene_django.converter import convert_django_field


class GeoJSON(graphene.Scalar):

    @classmethod
    def serialize(cls, value):
        return json.loads(value.geojson)


@convert_django_field.register(models.GeometryField)
def convert_field_to_geojson(field, registry=None):
    return graphene.Field(
        GeoJSON,
        description=field.help_text,
        required=not field.null)

Response:

{
    "id": "1",
    "location": {
        "type": "Point",
        "coordinates": [0.0, 1.0]
    }
}

Recently I have developed a library for Geographic types, inputs, filters… https://github.com/flavors/django-graphql-geojson

[EverWinter23]

Maybe this helps as well https://github.com/EverWinter23/graphene-gis