How to store a dictionary in a Django database model's field How to store a dictionary in a Django database model's field python python

How to store a dictionary in a Django database model's field


I just discovered the django-jsonfield package, which

is a reusable Django field that allows you to store validated JSON in your model.

Looks like a viable option to achieve what you want.


One convenient way to store a JSON representation in a model is to use a custom field type:

class JSONField(models.TextField):    """    JSONField is a generic textfield that neatly serializes/unserializes    JSON objects seamlessly.    Django snippet #1478    example:        class Page(models.Model):            data = JSONField(blank=True, null=True)        page = Page.objects.get(pk=5)        page.data = {'title': 'test', 'type': 3}        page.save()    """    __metaclass__ = models.SubfieldBase    def to_python(self, value):        if value == "":            return None        try:            if isinstance(value, basestring):                return json.loads(value)        except ValueError:            pass        return value    def get_db_prep_save(self, value, *args, **kwargs):        if value == "":            return None        if isinstance(value, dict):            value = json.dumps(value, cls=DjangoJSONEncoder)        return super(JSONField, self).get_db_prep_save(value, *args, **kwargs)

I saved this utils/fields.py and in my model from utils.fields import JSONField. There are many more goodies in the django-annoying app, which is where this snippet came from.


Using a custom field type is my preferred solution - I'd rather have a few lines of custom code than support an entire 3rd party library for a single field type. Tony Abou-Assaleh has a great solution, but won't work for newer versions of Django.

This is verified to work with Django 1.10.4

import jsonfrom django.db import modelsfrom django.core.serializers.json import DjangoJSONEncoderclass JSONField(models.TextField):    """    JSONField is a generic textfield that neatly serializes/unserializes    JSON objects seamlessly.    Django snippet #1478    example:        class Page(models.Model):            data = JSONField(blank=True, null=True)        page = Page.objects.get(pk=5)        page.data = {'title': 'test', 'type': 3}        page.save()    """    def to_python(self, value):        if value == "":            return None        try:            if isinstance(value, str):                return json.loads(value)        except ValueError:            pass        return value    def from_db_value(self, value, *args):        return self.to_python(value)    def get_db_prep_save(self, value, *args, **kwargs):        if value == "":            return None        if isinstance(value, dict):            value = json.dumps(value, cls=DjangoJSONEncoder)        return value