Django Rest Framework Dictionary Field

Question

I'm using Mongodb with mongoengine as a backend for a API in Django. The framework I'm using to create the api is Django Rest Framework.

I need to store a dictionary in a field in Mongo and the best I've done when the method post is called is to use a charfield and parse the dictionary in the function restore_object.

There is a better way to achieve this goal?

It's better to create a dict field? I don't know how hard this could be.

Thank you.

edited to show some code, notice that I store the dictionary as a dict (DictField) and it's content could change from one object to other.

my mongoengine model is something like:

class MyDoc(mongoengine.Document):
    name = mongoengine.StringField(max_length=200)
    context = mongoengine.DictField()

and my serializer something like:

class MyDocSerializer(serializers.Serializer):

    name = serializers.CharField(max_length=200)
    context = serializers.CharField()
    url = serializers.HyperlinkedIdentityField(
    view_name="drf:mydoc-detail",)

    def __init__(self,*args,**kwargs):
    super(MyDocSerializer,self).__init__(*args,**kwargs)


    def restore_object(self, attrs, instance=None):

    # Parse string to dict
    # this is so ugly, notice I had to repace ' for " to
    # avoid an error parsing the json
    context = JSONParser().parse(
    StringIO.StringIO(
        attrs['context'].replace("'","\"")
        )
    )

    attrs['context'] = context
    if instance is not None:
        instance.name = attrs['name']
        instance.context = context
        return instance

    return MyDoc(**attrs)

Answer 1

Rather than deal with the dictionary field in the Serializer's restore_object, you'll probably end up with something slightly cleaner, if instead you use a custom field for the dictionary field, that manages converting between the dictionary representation and internal char based storage.

You'll want to subclass serializers.WritableField and override the to_native() and from_native methods.

Relevant docs here.

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Note: WritableField class that was present in version 2.x no longer exists. You should subclass Field and override to_internal_value() if the field supports data input.

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Update: As of 3.0.4 you can now use serializers.DictField... http://www.django-rest-framework.org/api-guide/fields/#dictfield