Django Rest Framework - display prepopulated slug field - django

Question

I have a slug field for a model that I would like returned in the object representation but NOT as part of the form input in the browsable API. It is generated by a slugify method on the model.
When I mark it as read only in it's ModelSerializer by adding it to Meta using read_only_fields=('slug',) trying to add new fields in the browseable api form yields "This field is required."
The serializer for reference is below:
class CategorySerializer(serializers.HyperlinkedModelSerializer):
slug = serializers.SlugField(read_only=True, required=False)
def to_representation(self, obj):
self.fields['children'] = CategorySerializer(obj, many=True, read_only=True)
return super(CategorySerializer, self).to_representation(obj)
class Meta:
model = Category
fields = ('pk', 'url', 'title', 'slug', 'parent', 'children', 'active', 'icon')
read_only_fields = ('children','slug',)
What is a simple solution to show the field in the representation and not the browseable api form given the above?
For reference, here is my model:
#python_2_unicode_compatible
class CategoryBase(mptt_models.MPTTModel):
parent = mptt_fields.TreeForeignKey( 'self', blank=True, null=True, related_name='children', verbose_name=_('parent'))
title = models.CharField(max_length=100, verbose_name=_('name'))
slug = models.SlugField(verbose_name=_('slug'), null=True)
active = models.BooleanField(default=True, verbose_name=_('active'))
objects = CategoryManager()
tree = TreeManager()
def save(self, *args, **kwargs):
"""
While you can activate an item without activating its descendants,
It doesn't make sense that you can deactivate an item and have its
decendants remain active.
"""
if not self.slug:
self.slug = slugify(self.title)
super(CategoryBase, self).save(*args, **kwargs)
if not self.active:
for item in self.get_descendants():
if item.active != self.active:
item.active = self.active
item.save()
def __str__(self):
ancestors = self.get_ancestors()
return ' > '.join([force_text(i.title) for i in ancestors] + [self.title, ])
class Meta:
abstract = True
unique_together = ('parent', 'slug')
ordering = ('tree_id', 'lft')
class MPTTMeta:
order_insertion_by = 'title'
class Category(CategoryBase):
icon = IconField(null=True, blank=True)
order = models.IntegerField(default=0)
#property
def short_title(self):
return self.title
def get_absolute_url(self):
"""Return a path"""
from django.core.urlresolvers import NoReverseMatch
try:
prefix = reverse('categories_tree_list')
except NoReverseMatch:
prefix = '/'
ancestors = list(self.get_ancestors()) + [self, ]
return prefix + '/'.join([force_text(i.slug) for i in ancestors]) + '/'
def save(self, *args, **kwargs):
super(Category, self).save(*args, **kwargs)
class Meta(CategoryBase.Meta):
verbose_name = _('category')
verbose_name_plural = _('categories')