Drango之 drf(drango restful framework)--------------第一天
一.CBV源码分析
1 在views中写一个类,继承View,里面写get方法,post方法
2 在路由中配置: url(r'^test/', views.Test.as_view()),实际上第二个参数位置,放的还是一个函数内存地址
3 当请求来了,就会执行第二个参数(request,参数),本质上执行view()
4 view内部调用了dispatch()方法
5 dispatch分发方法,根据请求方式不同,执行的方法不同
二.resful规范
-面向资源架构,面向资源编程
-10个规范
-与后台做交互,通常使用https -域名: -https://api.baidu.com(存在跨域问题) -https://www.baidu.com/api/ -版本 -https://www.baidu.com/api/v1 -https://www.baidu.com/api/v2 -路径，视网络上任何东西都是资源，均使用名词表示（可复数） -https://api.example.com/v1/books 不是:https://api.example.com/v1/delete_one_book -method来表示增删查改 -https://api.example.com/v1/books get请求,获取所有书 -https://api.example.com/v1/books post请求,新增一本书 -https://api.example.com/v1/book/1 delete请求,删除一本书 -https://api.example.com/v1/book/1 get请求,获取id为1的这本书 -https://api.example.com/v1/book/1 put/patch请求,修改id为1的这本书 -过滤，通过在url上传参的形式传递搜索条件 -https://api.example.com/v1/books?limit=10：只拿前10本 -https://api.example.com/v1/books?price=10：只拿价格为10的书 -状态码 -{status:100,} -错误处理，应返回错误信息，error当做key { status:101, errors:'您没有权限操作这个事' } -返回结果，针对不同操作，服务器向用户返回的结果应该符合以下规范 GET /collection：返回资源对象的列表（数组） GET /collection/resource：返回单个资源对象 POST /collection：返回新生成的资源对象 PUT /collection/resource：返回完整的资源对象 PATCH /collection/resource：返回完整的资源对象 DELETE /collection/resource：返回一个空文档 -返回结果中提供链接(获取一本书) { id:1 name:lxx price:12 publish:www.xx.com/api/v1/publish/1 }
三.django中写resful的接口
views.py:
from django.shortcuts import render, HttpResponse from django.http import JsonResponse # Create your views here. from django.views import View class Test(View): def dispatch(self, request, *args, **kwargs): # 写代码 obj = super().dispatch(request, *args, **kwargs) # 写代码 return obj def get(self, request, *args, **kwargs): return HttpResponse('cbv_get') def post(self, request, *args, **kwargs): return HttpResponse('cbv_post') user_list = [{'id': 1, 'name': 'lqz', 'age': 18}, {'id': 2, 'name': 'egon', 'age': 17}, {'id': 3, 'name': 'xiaohou', 'age': 16}] def users(request): response = {'status': 100, 'errors': None} if request.method == 'GET': response['users'] = user_list return JsonResponse(response, safe=False) if request.method == 'POST': name = request.POST.get('name') age = request.POST.get('age') user_list.append({'id': len(user_list) + 1, 'name': name, 'age': age}) # response['user'] = {'id':len(user_list),'name': name, 'age': age} response['msg'] = '新增成功' return JsonResponse(response) def user(request, id): response = {'status': 100, 'errors': None} if request.method == 'GET': id = int(id) response['user'] = user_list[id] return JsonResponse(response)
url.py:
url(r'^test/', views.Test.as_view()), url(r'^users/', views.users), url(r'^user/(?P<id>\d+)', views.user),
前端渲染用postman
四.drf写resful的接口
-先安装
pip3 install djangorestframework
-简单使用
views.py:
from rest_framework.views import APIView
from rest_framework.response import Response
# 基于drf写接口,写cbv class DrfTest(APIView): def get(self, request, *args, **kwargs): # request是封装之后的request了,原来的request是request._request print(type(request._request)) print(type(request)) # 问:当前request对象并没有这些属性,但是能打印出来,为什么? # getattr print(request.method) print(request.POST) print(request.GET) # 就相当于: print(request.query_params) print(request._request.GET) response = {'status': 100, 'errors': None} response['users'] = user_list # 用drf的Response,可以通过请求客户端来判断返回数据格式是什么样的 return Response(response) # return JsonResponse(response) def post(self, request, *args, **kwargs): # post 提交的数据,urlencode,formdate,json格式,都能从data中取出来 name = request.data.get('name') # request.FILES print(name) return HttpResponse('ok')
url.py:
url(r'^users/', views.DrfTest.as_view()),
五.APIVIew源码分析
dispatch方法:
# 传入的request是原生的request对象
# 这个request已经不是原生的request了,但是它内部有个原生的request对象
request = self.initialize_request(request, *args, **kwargs)
self.initial(request, *args, **kwargs)#这里面有权限,认证,频率
六.drf之序列化: 把python中的对象,转成json格式字符串
url.py:
url(r'^books/', views.Books.as_view()), url(r'^book/(?P<id>\d+)', views.Book.as_view()),
myser.py:
from rest_framework import serializers # from rest_framework.request import Request class BookSerializer(serializers.Serializer): id = serializers.CharField() # 通过source可以改名 name = serializers.CharField(source='title') price = serializers.CharField() xxx = serializers.CharField(source='test') # 1 变量名和source指定的值不能一样 # 2 source='publish.name'还支持继续 . # 3 source 还支持方法(没用) # publish_name = serializers.CharField(source='publish.name') # publish_id = serializers.CharField(source='publish.pk') # 4 支持写方法,如下 #方法一定传一个参数,是当前book对象 publish_dic=serializers.SerializerMethodField() def get_publish_dic(self,obj): # 猜,这个obj应该是谁,当前book对象 return {'id':obj.publish.pk,'name':obj.publish.name}
views.py:
from app01 import models from app01.MySer import BookSerializer # 写一个获取所有图书的接口 class Books(APIView): def get(self, request, *args, **kwargs): response = {'status': 100, 'msg': '成功'} book_list = models.Book.objects.all() # 第一个参数是要序列化的queryset对象,如果序列化多条,必须指定many=True # 问?什么情况下many=False,instance=单个对象的时候 book_ser = BookSerializer(book_list, many=True) print(book_ser.data) response['books'] = book_ser.data return Response(response) class Book(APIView): def get(self, request, id): response = {'status': 100, 'msg': '成功'} book = models.Book.objects.filter(pk=id).first() book_ser = BookSerializer(book, many=False) response['book'] = book_ser.data return Response(response)
models.py:
from django.db import models # Create your models here. from django.db import models # Create your models here. class Book(models.Model): title = models.CharField(max_length=32) price = models.IntegerField() pub_date = models.DateField() publish = models.ForeignKey("Publish") authors = models.ManyToManyField("Author") def test(self): return self.title + str(self.price) def __str__(self): return self.title class Publish(models.Model): name = models.CharField(max_length=32) email = models.EmailField() # def __str__(self): # return self.name # return str(self.pk) class Author(models.Model): name = models.CharField(max_length=32) age = models.IntegerField() # # def __str__(self): # return self.name
七. 在线格式化json
-https://www.json.cn/
作业:
-研究一下什么是跨域
-图书的增删查该resful的接口写完,查的时候,返回所有的作者详情
