S11 day 94 RestFramework 之 APIView视图
VIEW视图（Django自带的）
1. url
url(r'login/$', views.login.as_view()),
2.点开 as_view() , as_view()为类方法. login类里面没有as_view方法，所以会到继承的View类中去找as_view方法.
from django.views import View class login(View): def get(self,request): return HttpResponse("get请求") def psot(self,request): return HttpResponse("post请求")
3. views.login.as_view() 等同于执行as_view方法。
web请求后一定会有一个函数方法的返回return 那么 ，我们看到下面as_view 方法里面 定义了view方法，整个as_view函数返回的就是view
相当于：
url(r'login/$', views.login.as_view()),
==> url(r'login/$', view), 执行view ，一但用户访问login，执行的view（request，*args,**kwargs）
==>url(r'login/$', view), 执行view 一但用户方法login，执行的是 return self.dispatch(request, *args, **kwargs)
self.dispatch()
最后执行dispatch方法 ，然后再看self 是谁的实例对象 ，这个self是谁取决于cls是谁（ self = cls(**initkwargs) ） ===>def as_view(cls, **initkwargs): , login 类调用的as_view ,所以 这个self实例对象为login类的self ， 那么我们就去login类里去找dispatch ，发现login里面我们并没有定义dispatch， 我们就去View基类里去找dispatch ，下面的dispatch 源码就是View基类里的源码dispatch方法。下面就来看dispatch里的执行顺序
，这个self为login 的类
as_view 源码
@classonlymethod def as_view(cls, **initkwargs): """ Main entry point for a request-response process. """ for key in initkwargs: if key in cls.http_method_names: raise TypeError("You tried to pass in the %s method name as a " "keyword argument to %s(). Don't do that." % (key, cls.__name__)) if not hasattr(cls, key): raise TypeError("%s() received an invalid keyword %r. as_view " "only accepts arguments that are already " "attributes of the class." % (cls.__name__, key)) def view(request, *args, **kwargs): self = cls(**initkwargs) if hasattr(self, 'get') and not hasattr(self, 'head'): self.head = self.get self.request = request self.args = args self.kwargs = kwargs return self.dispatch(request, *args, **kwargs) view.view_class = cls view.view_initkwargs = initkwargs # take name and docstring from class update_wrapper(view, cls, updated=()) # and possible attributes set by decorators # like csrf_exempt from dispatch update_wrapper(view, cls.dispatch, assigned=()) return view
dispatch方法里面 有个getattr 方法 ，handler 就是执行login类里的譬如get方法。
dispatch执行的结果就是handler的执行结果.
handler的执行就是self.get方法
dispatch源码
def dispatch(self, request, *args, **kwargs): # Try to dispatch to the right method; if a method doesn't exist, # defer to the error handler. Also defer to the error handler if the # request method isn't on the approved list. if request.method.lower() in self.http_method_names: handler = getattr(self, request.method.lower(), self.http_method_not_allowed) else: handler = self.http_method_not_allowed return handler(request, *args, **kwargs)
APIVIEW视图（restframework带的）
1. 设置二级路由.
url 路由
from django.conf.urls import url,include
from django.contrib import admin
from app01 import app01_url #导入二级路由文件
urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^api/', include(app01_url)),
#评论.
# url(r'^comment_list/', views.comment),
# url(r'^add_comment/', views.article_list),
# url(r'^delete_comment/', views.article_list),
]
二级路由 （在app目录下创建二级路由文件）
from django.conf.urls import url
from app01 import views
urlpatterns = [
url(r'^article/', views.index),
# url(r'article/(?P<pk>\d+)', views.ArticleDetail.as_view(), name='article-detail'),
# url(r'school/(?P<id>\d+)', views.SchoolDetail.as_view(), name='school-detail111'),
]
访问方法 ： http://127.0.0.1:8001/api/article/
序列化 文件
from app01.models import Comment,Article,School from rest_framework import serializers # 序列化评论类 class CommentSerializer(serializers.ModelSerializer): class Meta: model = Comment fields ="__all__" # depth =1 #序列化文章类 class ArticleModelSerializer(serializers.ModelSerializer): class Meta: model =Article fields ="__all__" # 学校的序列化 class SchoolSerializer(serializers.ModelSerializer): class Meta: model =School fields ="__all__"
2. 序列化+APIVIEW视图
A.GET请求
from rest_framework.views import APIView from app01 import serializers as app01_serializer from rest_framework.views import Response class Comment(APIView): def get(self,request): res={"code":0} #数据 all_comment =models.Comment.objects.all() #序列化 ser_obj =app01_serializer.CommentSerializer(all_comment,many=True) print('ser_obj-->:',ser_obj) res["data"] =ser_obj.data return Response(res)
打印结果：
B.POST请求
def post(self,request): res ={"code":0} #去提交的数据 comment_data = self.request.data print("comment-data---------->",comment_data) #对用户提交的数据做校验 ser_obj =app01_serializer.CommentSerializer(data=comment_data) if ser_obj.is_valid(): # 表示数据没有问题,可以创建 ser_obj.save() print('数据确认ok') else: #表示数据有问题 res["code"] =1 res["error"] =ser_obj.errors print('数据有问题') return Response(res)
打印结果：
3. 更改报错信息.
# 序列化评论类 class CommentSerializer(serializers.ModelSerializer): class Meta: model = Comment fields ="__all__" depth =1 #定义额外的参数. extra_kwargs={ "content":{ "error_messages":{ "required":"内容不能为空." } } }
结果：
4 .校验钩子 Validation
#用于做校验的钩子函数，类似于form组件的clean字段. #局部钩子 def validate_content(self,value): if "fuck" in value: raise ValidationError("不符合社会主义核心价值观") else: return value ==========以下代码没用上. #全局钩子 def validate(self, attrs): self.validated_data # 经过校验的数据,类似于form组件里的cleaned_data pass
结果：
在restframework 中 POST请求封装在 request.data里 ，request.data提供多种解析器 ,传json数据可以解析 ，urenccoded数据可以解析
