Djiango Rest Framwork

Django Rest Framework 介绍

一、什么是RESTful

  • REST与技术无关,代表的是一种软件的架构风格,
  • REST从资源的角度类审视整个网络,它将分布在网络中某个节点的资源通过URL进行标识,客户端应用通过URL来获取资源的表征,获得这些表征致使这些应用转变状态
  • 对于REST这种面向资源的构架风格,有人还提出一种全新的结构理念,即:面向资源架构

 

二、RESTful API设计的10种规范

  • 这里我们先提到一个名词:接口
    • 而接口本质上是一个url,而有时候在Java/C# 中是一种约束
    • 约束继承(实现)了他的类中必须含有接口中的方法
  1. method(根据method不同,进行不同操作)
    • GET:从服务器中取出资源
    • POST:从服务器上新建一个资源
    • PUT:从服务器上更新资源(客户端提供改变后的完整资源)
    • PATCH:从服务器上更新资源(客户端提供改变的资源)
    • DELECT:从服务器删除资源
  2. 面向资源编程(url的后缀是一个名词,我们可以对这个名词进行增删改查)
    • http://www.xxxx.com/salary
  3. 体现版本
    • http://www.luffycity.com/v1/salary
    • http://www.luffycity.com/v2/salary
  4. 体现api
    • http://www.luffycity.com/api/v1/salary
    • http://www.luffycity.com/api/v2/salary
  5. https(建议使用https--安全)
  6. 状态码
    • 200 OK - [GET]:服务器成功返回用户请求的数据,该操作是幂等的(Idempotent)。
      201 CREATED - [POST/PUT/PATCH]:用户新建或修改数据成功。
      202 Accepted - [*]:表示一个请求已经进入后台排队(异步任务)
      204 NO CONTENT - [DELETE]:用户删除数据成功。
      400 INVALID REQUEST - [POST/PUT/PATCH]:用户发出的请求有错误,服务器没有进行新建或修改数据的操作,该操作是幂等的。
      401 Unauthorized - [*]:表示用户没有权限(令牌、用户名、密码错误)。
      403 Forbidden - [*] 表示用户得到授权(与401错误相对),但是访问是被禁止的。
      404 NOT FOUND - [*]:用户发出的请求针对的是不存在的记录,服务器没有进行操作,该操作是幂等的。
      406 Not Acceptable - [GET]:用户请求的格式不可得(比如用户请求JSON格式,但是只有XML格式)。
      410 Gone -[GET]:用户请求的资源被永久删除,且不会再得到的。
      422 Unprocesable entity - [POST/PUT/PATCH] 当创建一个对象时,发生一个验证错误。
      500 INTERNAL SERVER ERROR - [*]:服务器发生错误,用户将无法判断发出的请求是否成功。
      View Code
  7. 条件
    • https://www.xxxx.com/api/v2/salary?page=1&size=10
  8. 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
  9. 错误处理,状态码是4xx时,应返回错误信息,error当做key
  10. Hypermedia API,RESTful API最好做到Hypermedia,即返回结果中提供链接,连向其他API方法,使得用户不查文档,也知道下一步应该做什么
    • ret = {
                      code: 1000,
                      data:{
                          id:1,
                          name:'小强',
                          depart_id:http://www.luffycity.com/api/v1/depart/8/
                      }
                  }

 Django rest Framework是干什么的呢?

  • 基于这个组件可以帮助我们开发,符合RESTful接口的,提供了一些功能
  • 实现什么功能了呢?
    • 请求进来--->经过路由视图,然后CBV可以继承好多类----->在rest framework源码中应该先走的是dispath而在dispath之前应该有版本控制-------->然后走的是 权限 认证频率------> 去解析器中拿数据-------->然后验证数据=序列化,------> 呈现数据=可能用到  分页 ----->选择器
    • 总结就是10种(上面绿色的10中)

 

创建一个快速实例

点我

创建一个实例化的类

简单的使用

models部分:

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 __str__(self):
        return self.title

class Publish(models.Model):
    name=models.CharField(max_length=32)
    email=models.EmailField()
    def __str__(self):
        return self.name

class Author(models.Model):
    name=models.CharField(max_length=32)
    age=models.IntegerField()
    def __str__(self):
        return self.name

views部分

from rest_framework.response import Response
from .models import *
from django.shortcuts import HttpResponse
from django.core import serializers

from rest_framework import serializers
from rest_framework.views import APIView
from rest_framework.response import Response
from .models import *
from django.shortcuts import HttpResponse
from django.core import serializers


from rest_framework import serializers

class BookSerializers(serializers.Serializer):
    title=serializers.CharField(max_length=32)
    price=serializers.IntegerField()
    pub_date=serializers.DateField()
    publish=serializers.CharField(source="publish.name")
    #authors=serializers.CharField(source="authors.all")
    authors=serializers.SerializerMethodField()
    def get_authors(self,obj):
        temp=[]
        for author in obj.authors.all():
            temp.append(author.name)
        return temp


class BookViewSet(APIView):

    def get(self,request,*args,**kwargs):
        book_list=Book.objects.all()
        # 序列化方式1:
        # from django.forms.models import model_to_dict
        # import json
        # data=[]
        # for obj in book_list:
        #     data.append(model_to_dict(obj))
        # print(data)
        # return HttpResponse("ok")

        # 序列化方式2:
        # data=serializers.serialize("json",book_list)
        # return HttpResponse(data)

        # 序列化方式3:
        bs=BookSerializers(book_list,many=True)
        return Response(bs.data)

 在app下新建一个类 创建一个ModelSerializer类来帮助序列化

class BookSerializers(serializers.ModelSerializer):
      class Meta:
          model=Book
          fields="__all__"
          depth=1

再次提交post请求时候

def get(self,request):

        # 取数据
        # print("request.data", request.data)
        # print("request.data type", type(request.data))
        # print(request._request.GET)
        # print(request.GET)
        # 序列化
        # 方式1:
        # publish_list=list(Publish.objects.all().values("name","email"))

        # 方式2:
        # from django.forms.models import model_to_dict
        # publish_list=Publish.objects.all()
        # temp=[]
        # for obj in publish_list:
        #     temp.append(model_to_dict(obj))

        # 方式3:
        # from django.core import serializers
        # ret=serializers.serialize("json",publish_list)

        # 序列组件
        publish_list = Publish.objects.all()
        ps = PublishModelSerializers(publish_list, many=True)
        return Response(ps.data)


def post(self , request,  *arg,**kwargs)

        bs = BookSerializers(data=request.data,many=False)
        # 单条数据默认是many = Fales
        #多条数据修改成many= True
    
        if bs.is_valid():
                # print(bs.validated_data)
                bs.save()
                return Response(bs.data)
        else:
                return HttpResponse(bs.errors)

    

重写save中的create方法

class BookSerializers(serializers.ModelSerializer):

      class Meta:
          model=Book
          fields="__all__"
          # exclude = ['authors',]
          # depth=1

      def create(self, validated_data):
        
          authors = validated_data.pop('authors')
          obj = Book.objects.create(**validated_data)
          obj.authors.add(*authors)
          return obj

单条数据的get和put方法

class BookDetailViewSet(APIView):

    def get(self,request,pk):
        book_obj=Book.objects.filter(pk=pk).first()
        bs=BookSerializers(book_obj)
        return Response(bs.data)

    def put(self,request,pk):
        book_obj=Book.objects.filter(pk=pk).first()
        bs=BookSerializers(book_obj,data=request.data)
        if bs.is_valid():
            bs.save()
            return Response(bs.data)
        else:
            return HttpResponse(bs.errors)

超链接API:Hyperlinked

class BookSerializers(serializers.ModelSerializer):
      publish= serializers.HyperlinkedIdentityField(
                     view_name='publish_detail',
                     lookup_field="publish_id",
                     lookup_url_kwarg="pk")
      class Meta:
          model=Book
          fields="__all__"
          #depth=1

url部分的修改

urlpatterns = [
    url(r'^books/$', views.BookViewSet.as_view(),name="book_list"),
    url(r'^books/(?P<pk>\d+)$', views.BookDetailViewSet.as_view(),name="book_detail"),
    url(r'^publishers/$', views.PublishViewSet.as_view(),name="publish_list"),
    url(r'^publishers/(?P<pk>\d+)$', views.PublishDetailViewSet.as_view(),name="publish_detail"),
] 

如果报错  :

解决方法:

视图创建的三种方式

mixings

视图部分

from rest_framework.views import APIView
from rest_framework.response import Response
from .models import *
from django.shortcuts import HttpResponse
from django.core import serializers


from rest_framework import serializers


class BookSerializers(serializers.ModelSerializer):
      class Meta:
          model=Book
          fields="__all__"
          #depth=1


class PublshSerializers(serializers.ModelSerializer):

      class Meta:
          model=Publish
          fields="__all__"
          depth=1


class BookViewSet(APIView):

    def get(self,request,*args,**kwargs):
        book_list=Book.objects.all()
        bs=BookSerializers(book_list,many=True,context={'request': request})
        return Response(bs.data)


    def post(self,request,*args,**kwargs):
        print(request.data)
        bs=BookSerializers(data=request.data,many=False)
        if bs.is_valid():
            print(bs.validated_data)
            bs.save()
            return Response(bs.data)
        else:
            return HttpResponse(bs.errors)


class BookDetailViewSet(APIView):

    def get(self,request,pk):
        book_obj=Book.objects.filter(pk=pk).first()
        bs=BookSerializers(book_obj,context={'request': request})
        return Response(bs.data)

    def put(self,request,pk):
        book_obj=Book.objects.filter(pk=pk).first()
        bs=BookSerializers(book_obj,data=request.data,context={'request': request})
        if bs.is_valid():
            bs.save()
            return Response(bs.data)
        else:
            return HttpResponse(bs.errors)


class PublishViewSet(APIView):

    def get(self,request,*args,**kwargs):
        publish_list=Publish.objects.all()
        bs=PublshSerializers(publish_list,many=True,context={'request': request})
        return Response(bs.data)


    def post(self,request,*args,**kwargs):

        bs=PublshSerializers(data=request.data,many=False)
        if bs.is_valid():
            # print(bs.validated_data)
            bs.save()
            return Response(bs.data)
        else:
            return HttpResponse(bs.errors)


class PublishDetailViewSet(APIView):

    def get(self,request,pk):

        publish_obj=Publish.objects.filter(pk=pk).first()
        bs=PublshSerializers(publish_obj,context={'request': request})
        return Response(bs.data)

    def put(self,request,pk):
        publish_obj=Publish.objects.filter(pk=pk).first()
        bs=PublshSerializers(publish_obj,data=request.data,context={'request': request})
        if bs.is_valid():
            bs.save()
            return Response(bs.data)
        else:
            return HttpResponse(bs.errors)

mixin类编写视图

from rest_framework import mixins
from rest_framework import generics

class BookViewSet(mixins.ListModelMixin,
                  mixins.CreateModelMixin,
                  generics.GenericAPIView):

    queryset = Book.objects.all()
    serializer_class = BookSerializers

    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        return self.create(request, *args, **kwargs)



class BookDetailViewSet(mixins.RetrieveModelMixin,
                    mixins.UpdateModelMixin,
                    mixins.DestroyModelMixin,
                    generics.GenericAPIView):
    queryset = Book.objects.all()
    serializer_class = BookSerializers

    def get(self, request, *args, **kwargs):
        return self.retrieve(request, *args, **kwargs)

    def put(self, request, *args, **kwargs):
        return self.update(request, *args, **kwargs)

    def delete(self, request, *args, **kwargs):
        return self.destroy(request, *args, **kwargs)

使用通用的的基于类的视图

通过使用mixin类,我们使用更少的代码重写了这些视图,但我们还可以再进一步。REST框架提供了一组已经混合好(mixed-in)的通用视图,我们可以使用它来简化我们的views.py模块。

 

from rest_framework import mixins
from rest_framework import generics

class BookViewSet(generics.ListCreateAPIView):

    queryset = Book.objects.all()
    serializer_class = BookSerializers

class BookDetailViewSet(generics.RetrieveUpdateDestroyAPIView):
    queryset = Book.objects.all()
    serializer_class = BookSerializers

class PublishViewSet(generics.ListCreateAPIView):

    queryset = Publish.objects.all()
    serializer_class = PublshSerializers

class PublishDetailViewSet(generics.RetrieveUpdateDestroyAPIView):
    queryset = Publish.objects.all()
    serializer_class = PublshSerializers

使用viewsets.ModelViewSet

urls.py

url(r'^books/$',views.BookViewSet.as_view({"get":"list","post":"create"}),name="book_list"),
url(r'^books/(?P<pk>\d+)$', views.BookViewSet.as_view({
                'get': 'retrieve',
                'put': 'update',
                'patch': 'partial_update',
                'delete': 'destroy'
            }),name="book_detail"),

views.py

class BookViewSet(viewsets.ModelViewSet):
    queryset = Book.objects.all()
    serializer_class = BookSerializers

 

 认证与权限组件

认证组件

局部视图的认证

在APP下的serviece/auth.py

from rest_framework import exceptions
from rest_framework.authentication import BaseAuthentication

from .models import *
class Authentication(BaseAuthentication):

    def authenticate(self,request):
        token=request._request.GET.get("token")
        token_obj=UserToken.objects.filter(token=token).first()
        if not token_obj:
            raise exceptions.AuthenticationFailed("验证失败!")
        return (token_obj.user,token_obj)

 

在views.py中

def get_random_str(user):
    import hashlib,time
    ctime=str(time.time())

    md5=hashlib.md5(bytes(user,encoding="utf8"))
    md5.update(bytes(ctime,encoding="utf8"))

    return md5.hexdigest()


from app01.service.auth import *

from django.http import JsonResponse
class LoginViewSet(APIView):
    authentication_classes = [Authentication,]
    def post(self,request,*args,**kwargs):
        res={"code":1000,"msg":None}
        try:
            user=request._request.POST.get("user")
            pwd=request._request.POST.get("pwd")
            user_obj=UserInfo.objects.filter(user=user,pwd=pwd).first()
            print(user,pwd,user_obj)
            if not user_obj:
                res["code"]=1001
                res["msg"]="用户名或者密码错误"
            else:
                token=get_random_str(user)
                UserToken.objects.update_or_create(user=user_obj,defaults={"token":token})
                res["token"]=token

        except Exception as e:
            res["code"]=1002
            res["msg"]=e

        return JsonResponse(res,json_dumps_params={"ensure_ascii":False})

全局的配置 

settings.py配置如下:

REST_FRAMEWORK={
    "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",]
}

 

 权限的组件

局部视图权限

在App.service.permissions.py

from rest_framework.permissions import BasePermission
class SVIPPermission(BasePermission):
    message="SVIP才能访问!"
    def has_permission(self, request, view):
        if request.user.user_type==3:
            return True
        return False

 

 在views.py:

from app01.service.permissions import *

class BookViewSet(generics.ListCreateAPIView):
    permission_classes = [SVIPPermission,]
    queryset = Book.objects.all()
    serializer_class = BookSerializers

 

 全局的视图权限

settings.py配置如下:

REST_FRAMEWORK={
    "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",],
    "DEFAULT_PERMISSION_CLASSES":["app01.service.permissions.SVIPPermission",]
}

 

 访问频率(throttle)组件

局部视图throttle

在app01.service.throttles.py中:

from rest_framework.throttling import BaseThrottle

VISIT_RECORD={}
class VisitThrottle(BaseThrottle):

    def __init__(self):
        self.history=None

    def allow_request(self,request,view):
        remote_addr = request.META.get('REMOTE_ADDR')
        print(remote_addr)
        import time
        ctime=time.time()

        if remote_addr not in VISIT_RECORD:
            VISIT_RECORD[remote_addr]=[ctime,]
            return True

        history=VISIT_RECORD.get(remote_addr)
        self.history=history

        while history and history[-1]<ctime-60:
            history.pop()

        if len(history)<3:
            history.insert(0,ctime)
            return True
        else:
            return False

    def wait(self):
        import time
        ctime=time.time()
        return 60-(ctime-self.history[-1])

在views.py中:

from app01.service.throttles import *

class BookViewSet(generics.ListCreateAPIView):
    throttle_classes = [VisitThrottle,]
    queryset = Book.objects.all()
    serializer_class = BookSerializers

全局视图的throttle

REST_FRAMEWORK={
    "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",],
    "DEFAULT_PERMISSION_CLASSES":["app01.service.permissions.SVIPPermission",],
    "DEFAULT_THROTTLE_CLASSES":["app01.service.throttles.VisitThrottle",]
}

 

内置的throttle类

在app01.service.throttles.py修改为:

class VisitThrottle(SimpleRateThrottle):

    scope="visit_rate"
    def get_cache_key(self, request, view):

        return self.get_ident(request)

 

settings.py设置:

REST_FRAMEWORK={
    "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",],
    "DEFAULT_PERMISSION_CLASSES":["app01.service.permissions.SVIPPermission",],
    "DEFAULT_THROTTLE_CLASSES":["app01.service.throttles.VisitThrottle",],
    "DEFAULT_THROTTLE_RATES":{
        "visit_rate":"5/m",
    }
}

 

 分页

简单分页

在views.py中

from rest_framework.pagination import PageNumberPagination,LimitOffsetPagination

class PNPagination(PageNumberPagination):
        page_size = 1
        page_query_param = 'page'
        page_size_query_param = "size"
        max_page_size = 5

class BookViewSet(viewsets.ModelViewSet):

    queryset = Book.objects.all()
    serializer_class = BookSerializers
    def list(self,request,*args,**kwargs):

        book_list=Book.objects.all()
        pp=LimitOffsetPagination()
        pager_books=pp.paginate_queryset(queryset=book_list,request=request,view=self)
        print(pager_books)
        bs=BookSerializers(pager_books,many=True)

        #return Response(bs.data)
        return pp.get_paginated_response(bs.data)

 

偏离分页

from rest_framework.pagination import LimitOffsetPagination

 

解析器

渲染器

版本

 

posted @ 2018-12-19 18:08  黑墨罗少  阅读(740)  评论(0)    收藏  举报