建立一個綁定serializer 類別的Django View

定義project 的urls

from django.contrib import admin
from django.urls import path
from django.conf.urls import url,include
urlpatterns = [
path('admin/', admin.site.urls),
url (r'^api/',include('app1.urls')),
]

定義app 的url

from django.contrib import admin
from django.urls import path
from django.conf.urls import url
from app1.views import person_list,person_detail
urlpatterns = [
path('admin/', admin.site.urls),
url (r'^person/$',person_list),
url (r'^person/(?P<pk>[0-9]+)$',person_detail),
]

定義Person models

from django.db import models
class Person(models.Model):
 name = models.CharField(max_length = 64)
 age = models.IntegerField()
 tel = models.CharField(max_length=64)
 
 def __str__(self):
  return "{} {} {}" % (self.name, self.age,self.tel)

撰寫Serializer 類別

當有人呼叫save 方法時，PersonSerializer 繼承自serializer.Serializer 然後override create 與update 方法。事實上，我們也必須實作這兩個方法，因為在serializer.Serializer 類別中宣告了NonImplementError 例外。

create 方法收到validated_data 資料後，傳回一個新的instance， update 方法找到一個已存在的instance，並透過validated_data 的參數進行更新

class PersonSerializer(serializers.Serializer):
 pk = serializers.IntegerField(read_only=True)
 name = serializers.CharField(max_length = 64)
 age = serializers.IntegerField( )
 tel = serializers.CharField(max_length = 64)
 
 def create (self,validated_data):
  return Person.objects.create(**validated_data)
  
 
 def update (self,instance,validated_data):
  instance.name = validated_data.get('name',instance.name)
  instance.age = validated_data.get('age',instance.age)
  instance.tel = validated_data.get('tel',instance.tel)
  instance.save()
  return instance

下面的例子為將 serializer.data 的JSON 字串轉到網頁

from django.shortcuts import render
from rest_framework.renderers import JSONRenderer
from django.views.decorators.csrf import csrf_exempt
from rest_framework import status
from app1.models import Person
from app1.serializers import PersonSerializer
from django.http import HttpResponse
from rest_framework.parsers import JSONParser
# Create your views here.
class JSONResponse(HttpResponse):
 def __init__(self,data,**kwargs):
 content =  JSONRenderer().render(data)
 kwargs['content_type'] = 'application/json'
 super(JSONResponse,self).__init__(content,**kwargs)
  
  
@csrf_exempt  
def person_list(request):
 if request.method == 'GET':
  person = Person.objects.all()
  person_serializer = PersonSerializer(person,many = True)
  return JSONResponse(person_serializer.data)  
 elif request.method == 'POST':
  person_data = JSONParser().parse(request)
  person_serializer = PersonSerializer(data = person_data)
 if person_serializer.is_valid():
  person_serializer.save()
  return JSONResponse(person_serializer.data,status = status.HTTP_201_CREATED)
 return JSONResponse(person_serializer.error,status = status.HTTP_404_NOT_FOUND)
@csrf_exempt
def person_detail(request,pk):
 try:
  person = Person.objects.get(pk = pk)  
 except:
  return HttpResponse(status = status.HTTP_404_NOT_FOUND)
if request.method == 'GET':  
  person_serializer = PersonSerializer(person)
  return JSONResponse(person_serializer.data)
if request.method == 'PUT':
  person_data = JSONParser().parse(request)
  person_serializer = PersonSerializer(person,data = person_data)
  if person_serializer.is_valid():
   person_serializer.save()
   return JSONResponse(person_serializer.data)  
 return JSONResponse(person_serializer.error,status = status.HTTP_404_NOT_FOUND)