Django Forms for generic relationships. How to include them? - django

Question

I have a Phone model that is being constantly used by many different models as a generic relationship. I have no idea how to include it in the Create/Update forms for those models… how good or bad of an idea is it to include the extra fields in a forms.ModelForm subclass… kind of like this:
###### models.py
class UpstreamContactModel(models.Model):
client = models.ForeignKey(UpstreamClientModel,
related_name='contacts')
contact_type = models.CharField(max_length=50, default='Main',
blank=True, null=True)
name = models.CharField(max_length=100, unique=True)
job_title = models.CharField(max_length=50, blank=True, null=True)
email = models.EmailField(blank=True, null=True)
skype_id = models.CharField(max_length=30, blank=True, null=True)
phones = generic.GenericRelation(Phone)
notes = models.TextField(blank=True, null=True)
def __unicode__(self):
return self.name
class Meta:
verbose_name = 'Contact'
class Phone(models.Model):
info = models.CharField('Eg. Office, Personal, etc',
max_length=15, blank=True)
number = models.CharField('Phone numbes', max_length=20)
# generic relationships so I can attach to other objects later on
content_type = models.ForeignKey(ContentType)
object_id = models.PositiveIntegerField()
content_object = generic.GenericForeignKey('content_type', 'object_id')
def __unicode__(self):
return self.number
##### forms.py
class ContactForm(forms.ModelForm, BaseValidationForm):
info = forms.CharField(max_length=15)
number = forms.CharField(max_length=20)
class Meta:
model = UpstreamContactModel
def clean(self):
???
def save(self):
???
I've been trying to find out how people handles CRUD when a generic relationship is involved but I've been unsuccessful at that so far.

Answer 1

If you use a model form you can see what kind of form elements they use.
For content_type it will typically use a ModelChoiceField with ContentType.objects.all() as the queryset, and object_id will be a TextInput looking for the positive integer. I don't think the actual generic accessor will show up in the form if you use a model form.
If you want a more elegant solution than this I'd look into writing a custom form field or widget to handle it.
I don't think it's bad practice to add additional fields to the ModelForm as you have, in fact I think that's a good route to go about it. Overriding the save method will probably give you the functionality you desire.