Generic View for listing, adding and removing items in ManyToManyField for django-rest-framework. Comes with an example =)

crudmanytomanyview.py

"""
        DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE 
                    Version 2, December 2004 

 Copyright (C) 2013 Eduardo Robles Elvira <edulix@wadobo.com> 

 Everyone is permitted to copy and distribute verbatim or modified 
 copies of this license document, and changing it is allowed as long 
 as the name is changed. 

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE 
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 

  0. You just DO WHAT THE FUCK YOU WANT TO.
"""

from __future__ import unicode_literals

from django.views.generic.detail import SingleObjectMixin
from django.views.generic.list import MultipleObjectMixin
from django.core.exceptions import ImproperlyConfigured

from rest_framework import views, mixins, generics, serializers
from rest_framework.settings import api_settings
from rest_framework.response import Response
from rest_framework import status


class CRUDManyToManyView(mixins.ListModelMixin, SingleObjectMixin,
                         generics.MultipleObjectAPIView):
    """
    Generic view that provide CRUD behaviour for ManyToMany fields.
    """
    model = None
    pk_url_kwarg = 'field_pk'
    field_name = ''
    model_pk = 'id'
    queryset = None
    item = None

    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        obj = self.get_object()
        item = self.get_item()
        getattr(self.get_item(), self.field_name).add(obj)
        item = self.get_item().save()
        return Response(status=status.HTTP_201_CREATED)

    def delete(self, request, *args, **kwargs):
        obj = self.get_object()
        item = self.get_item()
        getattr(self.get_item(), self.field_name).remove(obj)
        item = self.get_item().save()
        return Response(status=status.HTTP_204_NO_CONTENT)

    def get_item(self):
        if self.item:
            return self.item
        if self.model is None:
            raise ImproperlyConfigured("%(cls)s is missing a model." % {
                'cls': self.__class__.__name__
            })
        item_view = generics.SingleObjectAPIView()
        item_view.model = self.model
        item_view.request = self.request
        item_view.args = self.args
        item_view.kwargs = self.kwargs
        self.item = item_view.get_object()
        return self.item

    def get_queryset(self):
        '''
        Returns the list of items in model_instance.field_name.all()
        '''
        if self.queryset:
            return self.queryset
        if self.field_name is None:
            raise ImproperlyConfigured("%(cls)s is missing a field_name." % {
                'cls': self.__class__.__name__
            })

        obj = self.get_item()
        self.queryset = getattr(obj, self.field_name).all()
        return self.queryset

models.py

from django.db import models

class Task(models.Model):
    name = models.CharField(max_length=140, blank=False, null=False)

class Project(models.Model):
    name = models.CharField(max_length=140, blank=False, null=False)
    tasks = models.ManyToManyField(Task, related_name='projects')

serializers.py

from rest_framework import serializers
from models import Task

class TaskSerializer(serializers.ModelSerializer):
    class Meta:
        model = Task
        fields = ('id', 'name')

urls.py

from django.conf.urls import patterns, url
import views

urlpatterns = patterns(
'',
    url(r'^projects/(?P<pk>[0-9]+)/tasks/((?P<field_pk>[0-9]+)/)?$',
        views.ProjectTasks.as_view()),
)

views.py

from models import Project
from serializers import TaskSerializer
from lib.crudmanytomanyview import CRUDManyToManyView

class ProjectTasks(CRUDManyToManyView):
    model = Project
    field_name = 'tasks'
    serializer_class = TaskSerializer