Внедрение HATEOAS в среде Django REST

Question

Я пытаюсь реализовать REST API, который реализует HATEOAS с использованием Django REST Framework (DRF). Я знаю, что сам DRF не поддерживает HATEOAS, и я не нашел примеров такой реализации. Поэтому я не уверен, на каком уровне DRF (Serializers/Views/Renderers) я должен реализовать эту функциональность. У вас есть некоторые впечатления, мысли, идеи или примеры, которые могут помочь мне начать? Спасибо.

Answer 1

Вот мое решение, реализованное на уровне Viewset:

from rest_framework import viewsets 
from rest_framework import generics 
from serializers import EventSerializer, BandSerializer 
from rest_framework.response import Response 
from rest_framework import status 

from collections import OrderedDict 

class LinksAwarePageNumberPagination(PageNumberPagination): 
    def get_paginated_response(self, data, links=[]): 
     return Response(OrderedDict([ 
      ('count', self.page.paginator.count), 
      ('next', self.get_next_link()), 
      ('previous', self.get_previous_link()), 
      ('results', data), 
      ('_links', links), 
     ])) 

class HateoasModelViewSet(viewsets.ModelViewSet): 
    """ 
    This class should be inherited by viewsets that wants to provide hateoas links 
    You should override following methodes: 
     - get_list_links 
     - get_retrieve_links 
     - get_create_links 
     - get_update_links 
     - get_destroy_links 
    """ 

    pagination_class = LinksAwarePageNumberPagination 


    def get_list_links(self, request): 
     return {} 

    def get_retrieve_links(self, request, instance): 
     return {} 

    def get_create_links(self, request): 
     return {} 

    def get_update_links(self, request, instance): 
     return {} 

    def get_destroy_links(self, request, instance): 
     return {} 

    def get_paginated_response(self, data, links=None): 
     assert self.paginator is not None 
     return self.paginator.get_paginated_response(data, links) 

    def list(self, request, *args, **kwargs): 
     queryset = self.filter_queryset(self.get_queryset()) 

     page = self.paginate_queryset(queryset) 
     if page is not None: 
      serializer = self.get_serializer(page, many=True) 
      return self.get_paginated_response(serializer.data, links=self.get_list_links()) 

     serializer = self.get_serializer(queryset, many=True) 

     return Response(OrderedDict([ 
      ('results', serializer.data), 
      ('_links', self.get_list_links(request)) 
     ])) 

    def retrieve(self, request, *args, **kwargs): 
     instance = self.get_object() 
     serializer = self.get_serializer(instance) 
     data = serializer.data 
     data['_links'] = self.get_retrieve_links(request, instance) 
     return Response(data) 

    def create(self, request, *args, **kwargs): 
     serializer = self.get_serializer(data=request.data) 
     serializer.is_valid(raise_exception=True) 
     self.perform_create(serializer) 
     headers = self.get_success_headers(serializer.data) 
     data = serializer.data 
     data['_links'] = self.get_create_links(request) 
     return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers) 

    def update(self, request, *args, **kwargs): 
     partial = kwargs.pop('partial', False) 
     instance = self.get_object() 
     serializer = self.get_serializer(instance, data=request.data, partial=partial) 
     serializer.is_valid(raise_exception=True) 
     self.perform_update(serializer) 
     data = serializer.data 
     data['_links'] = self.get_update_links(request, instance) 
     return Response(serializer.data) 

    def destroy(self, request, *args, **kwargs): 
     instance = self.get_object() 
     data = {'_links': self.get_destroy_links(request, instance)} 
     self.perform_destroy(instance) 
     return Response(data, status=status.HTTP_204_NO_CONTENT) 

Пример использования:

class EventViewSet(HateoasModelViewSet): 
    queryset = Event.objects.all() 
    serializer_class = EventSerializer 

    def get_list_links(self, request): 
     return { 
      'self': {'href': request.build_absolute_uri(request.path)}, 
      'related_link1': {'href': '...'}, 
     }