Unable to use natural keys in django foreign key serialization

Question

So the thing is I have a class which has a foreign key.

This is my code

class Proxy(models.Model):
  class Meta:
    db_table = 'Proxy'
  equipment = models.ForeignKey('Equipment', primary_key=True)      
  pop = models.ForeignKey('Pop')

Now, as usual when I do

import django.core.serializers as Serializer
res = Proxy.objects.filter(equipment_id__exact='eq1')
Serializer.serialize('json', res)

the json output contains the "id" of the Pop and not the name, which I want.

So I used the Manager class and this is my Pop class now-

class PopManager(models.Manager):
  def get_by_natural_key(self, name):
    return self.get(name=name)

class Pop(models.Model):
  POP_TYPES = (
    ('phy','phy'),
    ('cloud','cloud'),
  )

  class Meta:
    db_table = 'Pop'
    unique_together = ('name', 'vip')
  objects = PopManager()
  name = models.CharField(max_length=10)
  type = models.CharField(max_length=10, choices=POP_TYPES)

  def natural_key(self):
    return (self.name)

But after this, when I do

res = Proxy.objects.filter(equipment_id__exact='eq1')
Serializer.serialize('json', res, use_natural_keys=True)

I get an error, TypeError: Equipment: eq1 is not JSON serializable

I have also tried wadofstuff for this serialization of foreign keys, but apparently in Django1.5, there is a clash between simplejson and json, and the query was throwing an error. So I am back to square one.

Any help will be highly appereciated. I have been splitting my hair for hours.

instead of `res` in `serialize()` try `list(res)`. – Bibhas Debnath Mar 31 '13 at 10:59 — Bibhas Debnath, Mar 31 '13 at 10:59
Yeah, I did that already. Same result. – Agniva De Sarker Mar 31 '13 at 19:20 — Agniva De Sarker, Mar 31 '13 at 19:20

score 0 · Answer 1 · answered Mar 31 '13 at 19:22

0

Anyway, so I solved this by converting the QuerySet to a raw dictionary type format. I appended a values clause after filter. And looped through the entire queryset returned to make a list of dictionaries. The rest was easy.

answered Mar 31 '13 at 19:22

Agniva De Sarker

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score 0 · Answer 2 · answered Nov 13 '13 at 17:35

0

Agniva,

You just need to delete your line:

db_table = 'Pop'

answered Nov 13 '13 at 17:35

Diego Perez Salas

1

Unable to use natural keys in django foreign key serialization

2 Answers2