Django: Converting an entire Model into a single dictionary

Question

Is there a good way in Django to convert an entire model to a dictionary? I mean, like this:

class DictModel(models.Model):
    key = models.CharField(20)
    value = models.CharField(200)


DictModel.objects.all().to_dict()

... with the result being a dictionary with the key/value pairs made up of records in the Model? Has anyone else seen this as being useful for them?

Thanks.

Update
I just wanted to add is that my ultimate goal is to be able to do a simple variable lookup inside a Template. Something like:

{{ DictModel.exampleKey }}

With a result of DictModel.objects.get(key__exact=exampleKey).value

Overall, though, you guys have really surprised me with how helpful allof your responses are, and how different the ways to approach it can be. Thanks a lot.

Answer 1

You are looking for the Values member of QuerySet which allows you to get a list of dictionaries from your query

Returns a ValuesQuerySet -- a QuerySet that evaluates to a list of dictionaries instead of model-instance objects. Each of those dictionaries represents an object, with the keys corresponding to the attribute names of model objects.

>>> Blog.objects.values()
[{'id': 1, 'name': 'Beatles Blog', 'tagline': 'All the latest Beatles news.'}],
>>> Blog.objects.values('id', 'name')
[{'id': 1, 'name': 'Beatles Blog'}]

Answer 2

use

dict(((m.key, m.value) for m in DictModel.objects.all())

As suggested by Tom Leys, we do not need to get whole object, we can get only those values we need e.g.

dict(((m['key'], m['value']) for m in DictModel.objects.values('key', 'value')))

and if you need all values, it is better to keep whole object in dict e.g.

dict(((m.key, m) for m in DictModel.objects.all())

Answer 3

Does this need to create an actual dict? could you get by with only something that looked like a dict?

class DictModelAdaptor():
    def __init__(self, model):
        self.model = model

    def __getitem__(self, key):
        return self.model.objects.get(key=key)

    def __setitem__(self, key, item):
        pair = self.model()
        pair.key = key
        pair.value = item
        pair.save()

    def __contains__(self, key):
        ...

You could then wrap a model in this way:

modelDict = DictModelAdaptor(DictModel)
modelDict["name"] = "Bob Jones"

etc...

Answer 4

You can use the python serializer:

from django.core import serializers
data = serializers.serialize('python', DictModel.objects.all())

Answer 5

You want the in_bulk queryset method which, according to the docs:

Takes a list of primary-key values and returns a dictionary mapping each primary-key value to an instance of the object with the given ID.

It takes a list of IDs, so you'll need to get that first via the values_list method:

ids = MyModel.objects.values_list('id', flat=True)
model_dict = MyModel.objects.in_bulk(ids)

Answer 6

You can also rely on django code already written ;).

from django.forms.models import model_to_dict
model_to_dict(intance, fields=[], exclude=[])

Regards Arthur

Answer 7

Or were you trying to do something like:

def someview(req):
    models = MyModel.objects.all()
    toTuple = lambda field: (getattr(field, 'someatt'), getattr(field, 'someotheratt'))  
    data = dict(map(toTuple,models))
    return render_to_response(template, data)

Answer 8

dict((x.name, getattr(o, x.name)) for x in o._meta.fields)