restframework詳細

1.寫視圖的方法

1.1第一種：原始APIView

url(r'^login/$',account.LoginView.as_view()),

from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework_jwt.settings import api_settings
from rest_framework.throttling import AnonRateThrottle
from api import models


class LoginView(APIView):
    authentication_classes = []
    def post(self,request,*args,**kwargs):
        # 1.根據用戶名和密碼檢測用戶是否能夠登陸
        user = models.UserInfo.objects.filter(username=request.data.get('username'),password=request.data.get('password')).first()
        if not user:
            return Response({'code':10001,'error':'用戶名或密碼錯誤'})

        # 2. 根據user對象生成payload（中間值的數據）
        jwt_payload_handler = api_settings.JWT_PAYLOAD_HANDLER
        payload = jwt_payload_handler(user)

        # 3. 構造前面數據，base64加密；中間數據base64加密；前兩段拼接而後作hs256加密（加鹽），再作base64加密。生成token
        jwt_encode_handler = api_settings.JWT_ENCODE_HANDLER
        token = jwt_encode_handler(payload)
        return Response({'code': 10000, 'data': token})

1.2第二種：ListApiView等

url(r'^article/$',article.ArticleView.as_view()),
url(r'^article/(?P<pk>\d+)/$',article.ArticleDetailView.as_view()),

from rest_framework.throttling import AnonRateThrottle
from rest_framework.response import Response
from rest_framework.generics import ListAPIView,RetrieveAPIView
from api import models
from api.serializer.article import ArticleSerializer,ArticleDetailSerializer

class ArticleView(ListAPIView):
    authentication_classes = []
    # throttle_classes = [AnonRateThrottle,]

    queryset = models.Article.objects.all()
    serializer_class = ArticleSerializer

class ArticleDetailView(RetrieveAPIView):
    authentication_classes = []
    queryset = models.Article.objects.all()
    serializer_class = ArticleDetailSerializer

1.3第三種：

url(r'^article/$',article.ArticleView.as_view({"get":'list','post':'create'})),
    url(r'^article/(?P<pk>\d+)/$',article.ArticleView.as_view({'get':'retrieve','put':'update','patch':'partial_update','delete':'destroy'}))

from rest_framework.viewsets import GenericViewSet
from rest_framework.mixins import ListModelMixin,RetrieveModelMixin,CreateModelMixin,UpdateModelMixin,DestroyModelMixin
from api.serializer.article import ArticleSerializer,ArticleDetailSerializer

class ArticleView(GenericViewSet,ListModelMixin,RetrieveModelMixin,CreateModelMixin,UpdateModelMixin,DestroyModelMixin):
    authentication_classes = []
    throttle_classes = [AnonRateThrottle,]

    queryset = models.Article.objects.all()
    serializer_class = None

    def get_serializer_class(self):
        pk = self.kwargs.get('pk')
        if pk:
            return ArticleDetailSerializer
        return ArticleSerializer

2.drf 相關知識點梳理

2.1裝飾器

def outer(func):
    def inner(*args,**kwargs):
        return func(*args,**kwargs)
    return inner

@outer
def index(a1):
    pass

index()

def outer(func):
    def inner(*args,**kwargs):
        return func(*args,**kwargs)
    return inner

def index(a1):
    pass

index = outer(index)

index()

2.2django中能夠免除csrftoken認證

from django.views.decorators.csrf import csrf_exempt
from django.shortcuts import HttpResponse

@csrf_exempt
def index(request):
    return HttpResponse('...')

# index = csrf_exempt(index)

urlpatterns = [
    url(r'^index/$',index),
]

urlpatterns = [
    url(r'^login/$',account.LoginView.as_view()),
]

class APIView(View):
    @classmethod
    def as_view(cls, **initkwargs):
        view = super().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)

2.3面向對象中基於繼承+異常處理來作的約束

class BaseVersioning:
    def determine_version(self, request, *args, **kwargs):
        raise NotImplementedError("must be implemented")
        
class URLPathVersioning(BaseVersioning):
    def determine_version(self, request, *args, **kwargs):
        version = kwargs.get(self.version_param, self.default_version)
        if version is None:
            version = self.default_version

        if not self.is_allowed_version(version):
            raise exceptions.NotFound(self.invalid_version_message)
        return version

2.4面向對象封裝

class Foo(object):
    def __init__(self,name,age):
        self.name = name
        self.age = age 
        
obj = Foo('汪洋',18)

class APIView(View):
    def dispatch(self, request, *args, **kwargs):

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

        return Request( # 給request再封裝一層
            request,
            parsers=self.get_parsers(),
            authenticators=self.get_authenticators(), # [MyAuthentication(),]
            negotiator=self.get_content_negotiator(),
            parser_context=parser_context
        )

2.5面向對象繼承

class View(object):
    pass

class APIView(View):
    def dispatch(self):
        method = getattr(self,'get')
        method()

class GenericAPIView(APIView):
    serilizer_class = None
    
    def get_seriliser_class(self):
        return self.serilizer_class

class ListModelMixin(object):
    def get(self):
        ser_class = self.get_seriliser_class()
        print(ser_class)

class ListAPIView(ListModelMixin,GenericAPIView):
    pass

class UserInfoView(ListAPIView):
    pass


view = UserInfoView()
view.dispatch()

class View(object):
    pass

class APIView(View):
    def dispatch(self):
        method = getattr(self,'get')
        method()

class GenericAPIView(APIView):
    serilizer_class = None
    
    def get_seriliser_class(self):
        return self.serilizer_class

class ListModelMixin(object):
    def get(self):
        ser_class = self.get_seriliser_class()
        print(ser_class)

class ListAPIView(ListModelMixin,GenericAPIView):
    pass

class UserInfoView(ListAPIView):
    serilizer_class = "汪洋"


view = UserInfoView()
view.dispatch()

class View(object):
    pass

class APIView(View):
    def dispatch(self):
        method = getattr(self,'get')
        method()

class GenericAPIView(APIView):
    serilizer_class = None
    
    def get_seriliser_class(self):
        return self.serilizer_class

class ListModelMixin(object):
    def get(self):
        ser_class = self.get_seriliser_class()
        print(ser_class)

class ListAPIView(ListModelMixin,GenericAPIView):
    pass

class UserInfoView(ListAPIView):
    
    def get_seriliser_class(self):
        return "咩咩"

view = UserInfoView()
view.dispatch()

2.6反射

class View(object):
    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)

2.7發送ajax請求

$.ajax({
    url:'地址',
    type:'GET',
    data:{...},
    success:function(arg){
        console.log(arg);
    }
})

• 簡單請求，發送一次請求。
• 複雜請求，先options請求作預檢，而後再發送真正請求

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <h1>常鑫的網站</h1>
    <p>
        <input type="button" value="點我" onclick="sendMsg()">
    </p>
    <p>
        <input type="button" value="點他" onclick="sendRemoteMsg()">
    </p>

  
    <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
    <script>
        function sendMsg() {
            $.ajax({
                url:'/msg/',
                type:'GET',
                success:function (arg) {
                    console.log(arg);
                }
            })
        }
        function sendRemoteMsg() {
            $.ajax({
                url:'http://127.0.0.1:8002/json/',
                type:'GET',
                success:function (arg) {
                    console.log(arg);
                }
            })

        }
    </script>
</body>
</html>

2.8如何解決ajax+跨域？

CORS，跨站資源共享，本質：設置響應頭。

2.9常見的Http請求方法

get
post
put
patch
delete
options

2.10http請求中Content-type請起頭

狀況一：
    content-type:x-www-form-urlencode
    name=alex&age=19&xx=10
    
    request.POST和request.body中均有值。
    
狀況二：
    content-type:application/json
    {"name":"ALex","Age":19}
    
    request.POST沒值
    request.body有值。

2.11django中F查詢

2.12django中獲取空Queryset

models.User.object.all().none()

2.13基於django的fbv和cbv都能實現遵循restful規範的接口

def user(request):
    if request.metho == 'GET':
        pass
    
    
class UserView(View):
    def get()...
    
    def post...

2.14基於django rest framework框架實現restful api的開發。

- 免除csrf認證
- 視圖（APIView、ListAPIView、ListModelMinx）
- 版本
- 認證
- 權限
- 節流
- 解析器
- 篩選器
- 分頁
- 序列化
- 渲染器

2.15簡述drf中認證流程？

2.16簡述drf中節流的實現原理以及過程？匿名用戶/非匿名用戶 如何實現頻率限制？

2.17GenericAPIView視圖類的做用？

他提供了一些規則，例如：

class GenericAPIView(APIView):
    serializer_class = None
    queryset = None
    lookup_field = 'pk'
    
    filter_backends = api_settings.DEFAULT_FILTER_BACKENDS
    pagination_class = api_settings.DEFAULT_PAGINATION_CLASS
    
    def get_queryset(self):
        return self.queryset
    
    def get_serializer_class(self):
        return self.serializer_class
    
    def filter_queryset(self, queryset):
        for backend in list(self.filter_backends):
            queryset = backend().filter_queryset(self.request, queryset, self)
        return queryset
    
    @property
    def paginator(self):
        if not hasattr(self, '_paginator'):
            if self.pagination_class is None:
                self._paginator = None
            else:
                self._paginator = self.pagination_class()
        return self._paginator
    
他至關於提供了一些規則，建議子類中使用固定的方式獲取數據，例如：
class ArticleView(GenericAPIView):
    queryset = models.User.objects.all()
    
    def get(self,request,*args,**kwargs):
        query = self.get_queryset()

咱們能夠本身繼承GenericAPIView來實現具體操做，可是通常不會，由於更加麻煩。
而GenericAPIView主要是提供給drf內部的 ListAPIView、Create....
class ListModelMixin:
    def list(self, request, *args, **kwargs):
        queryset = self.filter_queryset(self.get_queryset())

        page = self.paginate_queryset(queryset)
        if page is not None:
            serializer = self.get_serializer(page, many=True)
            return self.get_paginated_response(serializer.data)

        serializer = self.get_serializer(queryset, many=True)
        return Response(serializer.data)
    
class ListAPIView(mixins.ListModelMixin,GenericAPIView):
    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)

class MyView(ListAPIView):
    queryset = xxxx 
    ser...

總結：GenericAPIView主要爲drf內部幫助咱們提供增刪改查的類LIstAPIView、CreateAPIView、UpdateAPIView、提供了執行流程和功能，咱們在使用drf內置類作CURD時，就能夠經過自定義 靜態字段（類變量）或重寫方法（get_queryset、get_serializer_class）來進行更高級的定製。

2.18jwt以及其優點。

2.19序列化時many=True和many=False的區別？

2.20應用DRF中的功能進行項目開發

*****
    解析器:request.query_parmas/request.data
    視圖
    序列化
    渲染器：Response

****
    request對象封裝
    版本處理
    分頁處理
***
    認證
    權限
    節流

• 基於APIView實現呼啦圈
• 繼承ListAPIView+ GenericViewSet,ListModelMixin實現呼啦圈