Django-RESTful Api之请求与响应

配置应用

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'myApp',
    'rest_framework',
]

Request对象

• **request.POST：**只能处理表单数据，并且只能处理POST请求
• **request.data：**能处理各种请求数据，可以处理PUT和PATCH请求的数据

Response对象

• **JsonResponse类：**用于返回json格式的响应数据，在return的时候需要指明json格式
• **Reponse类：**会根据客户端的请求头部信息来返回正确的内容类型

状态码

• 发送http请求是会返回各种各样的状态码，但是都是数字，这些数字不能够明确的让程序员了解错误
• HTTP_400_BAD_REQUEST极大的提高可读性

视图

• **@api_view：**是装饰器，用在基于函数的视图上
• **APIView：**是类，用在基于类的视图上
• **注意：**提供一些功能，让程序员节省工作量，接收到错误的request.data抛出parseError，或者在适当时候返回405状态码

应用扩展

from myApp.models import Student, Grade
from myApp.serializers import StudentSerializer
from rest_framework.decorators import api_view
from rest_framework.response import Response
from rest_framework import status


# Create your views here.
@api_view(["GET", "POST"])
def studentsList(request):
    if request.method == "GET":
        stus = Student.objects.all()
        serializer = StudentSerializer(stus, many=True)
        # 不需要指定json格式，返回给客户端的可以json也可以是HTML等类型的数据，如果返回会的是HTML，会在浏览器经过渲染展示
        return Response(serializer.data, status=status.HTTP_200_OK)
    elif request.method == "POST":
        serializer = StudentSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)


@api_view(["GET", "PUT", "DELETE"])
def studentDetail(request, pk):
    try:
        stu = Student.objects.get(pk=pk)
    except Student.DoesNotExist as e:
        return Response(status=status.HTTP_404_NOT_FOUND)
    if request.method == "GET":
        serializer = StudentSerializer(stu)
        return Response(serializer.data, status=status.HTTP_200_OK)
    elif request.method == "PUT":
        serializer = StudentSerializer(stu, data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
    elif request.method == "DELETE":
        stu.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)

向URL添加可选的格式后缀

• 视图：

  def studentsList(request, format=None)

  def studentDetail(request, pk, format=None)

• 路由：

  from django.conf.urls import url
  from myApp import views
  # 格式后缀
  from rest_framework.urlpatterns import format_suffix_patterns
  
  urlpatterns = [
  
      url(r'^students/$', views.studentsList),
      url(r'^students/(?P<pk>\d+)', views.studentDetail),
  ]
  urlpatterns = format_suffix_patterns(urlpatterns)

• 测试：

  http://127.0.0.1:8000/students.api
  http://127.0.0.1:8000/students.json

• 示例：

  from myApp.models import Student, Grade
  from myApp.serializers import StudentSerializer
  from rest_framework.decorators import api_view
  from rest_framework.response import Response
  from rest_framework import status
  
  
  # Create your views here.
  @api_view(["GET", "POST"])
  def studentsList(request, format=None):
      if request.method == "GET":
          stus = Student.objects.all()
          serializer = StudentSerializer(stus, many=True)
          # 不需要指定json格式，返回给客户端的可以json也可以是HTML等类型的数据，如果返回会的是HTML，会在浏览器经过渲染展示
          return Response(serializer.data, status=status.HTTP_200_OK)
      elif request.method == "POST":
          serializer = StudentSerializer(data=request.data)
          if serializer.is_valid():
              serializer.save()
              return Response(serializer.data, status=status.HTTP_201_CREATED)
          return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
  
  
  @api_view(["GET", "PUT", "DELETE"])
  def studentDetail(request, pk, format=None):
      try:
          stu = Student.objects.get(pk=pk)
      except Student.DoesNotExist as e:
          return Response(status=status.HTTP_404_NOT_FOUND)
      if request.method == "GET":
          serializer = StudentSerializer(stu)
          return Response(serializer.data, status=status.HTTP_200_OK)
      elif request.method == "PUT":
          serializer = StudentSerializer(stu, data=request.data)
          if serializer.is_valid():
              serializer.save()
              return Response(serializer.data, status=status.HTTP_201_CREATED)
          return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
      elif request.method == "DELETE":
          stu.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)