Django REST framework 基本组件

一、序列化组件

简单使用

开发我们的web api的第一件事是为我们的web api提供一种将代码片段实例序列化和反序列化为诸如json之类的表示形式的方式。我们可以通过声明与django forms非常相似的序列化器（serializers）来实现。

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.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)

modelserializer

class bookserializers(serializers.modelserializer):
      class meta:
          model=book
          fields="__all__"
          depth=1

提交post请求

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

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请求

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

urls部分：

`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"``),``]`

二、视图组件之视图三部曲

使用混合（mixins）

上一节的视图部分：

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

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

三、认证组件

局部视图认证

在app01.service.auth.py:

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：

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})

全局视图认证组件

settings.py配置如下：

`rest_framework``=``{``    ``"default_authentication_classes"``:[``"app01.service.auth.authentication"``,]``}`

四、权限组件

局部视图权限

在app01.service.permissions.py中：

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"``,]``}`

五、throttle(访问频率)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",
    }
}

六、解析器

request类

django的request类和rest-framework的request类的源码解析

局部视图

from rest_framework.parsers import jsonparser,formparser
class publishviewset(generics.listcreateapiview):
    parser_classes = [formparser,jsonparser]
    queryset = publish.objects.all()
    serializer_class = publshserializers
    def post(self, request, *args, **kwargs):
        print("request.data",request.data)
        return self.create(request, *args, **kwargs)

全局视图

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",
    },
    "default_parser_classes":['rest_framework.parsers.formparser',]
}

七、分页

简单分页

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)

偏移分页

from rest_framework.pagination import limitoffsetpagination