rest-framework之APIView

一 安装djangorestframework

方式一：pip3 install djangorestframework

方式二：pycharm图形化界面安装

方式三：pycharm命令行下安装（装在当前工程所用的解释器下）

 

二  djangorestframework的APIView分析

 导入APIView

from 

 as_view 方法

@classmethod
    def as_view(cls, **initkwargs):
        """
        Store the original class on the view function.

        This allows us to discover information about the view when we do URL
        reverse lookups.  Used for breadcrumb generation.
        """
        if isinstance(getattr(cls, 'queryset', None), models.query.QuerySet):
            def force_evaluation():
                raise RuntimeError(
                    'Do not evaluate the `.queryset` attribute directly, '
                    'as the result will be cached and reused between requests. '
                    'Use `.all()` or call `.get_queryset()` instead.'
                )
            cls.queryset._fetch_all = force_evaluation

        view = super(APIView, cls).as_view(**initkwargs)
        view.cls = cls
        view.initkwargs = initkwargs

        # Note: session based authentication is explicitly CSRF validated,
        # all other authentication is CSRF exempt.
        return csrf_exempt(view)

as_view方法通过继承父类as_view方法并且对csrf做了处理

 

dis_patch方法

def dispatch(self, request, *args, **kwargs):
        """
        `.dispatch()` is pretty much the same as Django's regular dispatch,
        but with extra hooks for startup, finalize, and exception handling.
        """
  
      self.args = args
        self.kwargs = kwargs
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            self.initial(request, *args, **kwargs)

            # Get the appropriate handler method
            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

            response = handler(request, *args, **kwargs)

        except Exception as exc:
            response = self.handle_exception(exc)
        self.response = self.finalize_response(request, response, *args, **kwargs)
        return self.response

dispatch方法通过客户端的请求方法来分发到视图函数中cbv中的对应方法

 

initialize_request方法

    def initialize_request(self, request, *args, **kwargs):
        """
        Returns the initial request object.
        """
        parser_context = self.get_parser_context(request)

        return Request(
            request,
            parsers=self.get_parsers(),
            authenticators=self.get_authenticators(),
            negotiator=self.get_content_negotiator(),
            parser_context=parser_context
        )


#将django中的request进行了封装，为其添加了解析器，认证，权限，频率等功能

 

 initial方法

def initial(self, request, *args, **kwargs):
        """
        Runs anything that needs to occur prior to calling the method handler.
        """
        self.format_kwarg = self.get_format_suffix(**kwargs)

        # Perform content negotiation and store the accepted info on the request
        neg = self.perform_content_negotiation(request)
        request.accepted_renderer, request.accepted_media_type = neg

        # Determine the API version, if versioning is in use.
        version, scheme = self.determine_version(request, *args, **kwargs)
        request.version, request.versioning_scheme = version, scheme

        # Ensure that the incoming request is permitted
        self.perform_authentication(request)
        self.check_permissions(request)
        self.check_throttles(request)

initial方法（内部调用认证，权限和频率）

三 djangorestframework的Request对象简单介绍

 

 __getattr__ 方法

通过点号拦截方法，当对象点属性时，找不到会触发

 

__setattr__方法

赋值拦截方法，当对象点属性赋值时，原本没有这个属性会触发

 

data 方法

不管请求方法是什么，request.data都会将前台的发送的数据转成字典