day74 作业

完成汽车系统表模型的建立（表关系自己设计）
汽车表、汽车商家表、赞助商表、赞助商详情表

完成汽车系统的接口编写
汽车表：八大接口(不需要写put方法)
汽车商家表：八大接口(不需要写put方法)

模型层

from django.db import models


# Create your models here.

class BaseModel(models.Model):
    is_delete = models.BooleanField(default=False)
    create_time = models.DateTimeField(auto_now_add=True)

    class Meta:
        # 基表，为抽象表，是专门用来被继承，提供公有字段的，自身不会完成数据库迁移
        abstract = True
        
class Car(BaseModel):
    name = models.CharField(max_length=64)
    price = models.DecimalField(max_digits=10, decimal_places=2)
    merchant = models.ForeignKey(to='Merchant', related_name='cars', db_constraint=False, on_delete=models.DO_NOTHING)
    sponsor = models.ForeignKey(to='Sponsor', related_name='cars', db_constraint=False, on_delete=models.DO_NOTHING)

    @property
    def merchant_info(self):
        return {
            'name': self.merchant.name,
            'address': self.merchant.address
        }

    @property
    def sponsor_list(self):
        sponsor_list_temp = []  # 存放所有作者格式化成数据的列表
        sponsors = self.sponsor.all()  # 所有作者
        for sponsor in sponsors:  # 遍历处理所有作者
            sponsor_dic = {
                'name': sponsor.name,
            }
            try:  # 有详情才处理详情信息
                sponsor_dic['model'] = sponsor.detail.mobile
            except:
                sponsor_dic['model'] = '无'
                sponsor_list_temp.append(sponsor_dic)  # 将处理过得数据添加到数据列表中
        return sponsor_list_temp  # 返回处理后的结果

    def __str__(self):
        return self.name
class Merchant(BaseModel):
    name = models.CharField(max_length=64)


class Sponsor(BaseModel):
    name = models.CharField(max_length=64)


class SponsorDetail(BaseModel):
    mobile = models.CharField(max_length=64)
    sponsor = models.OneToOneField(to=Sponsor, related_name='detail', db_constraint=False, on_delete=models.DO_NOTHING)

视图层

from django.shortcuts import render
from rest_framework.views import APIView
from rest_framework.response import Response
from . import models, serializers
from .response import APIResponse
class CarAPIView(APIView):
    # 单查群查
    def get(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:
            car_obj = models.Car.objects.filter(is_delete=False, pk=pk).first()
            car_ser = serializers.CarModelSerializer(car_obj)
        else:
            car_query = models.car.objects.filter(is_delete=False).all()
            car_ser = serializers.CarModelSerializer(car_query, many=True)
        return APIResponse(results=car_ser.data)

    # 单删群删
    def delete(self, request, *args, **kwargs):

        pk = kwargs.get('pk')
        if pk:
            pks = [pk]  # 将单删格式化成群删的一条
        else:
            pks = request.data  # 群删
        try:  # 数据如果有误，数据库执行会出错
            rows = models.Car.objects.filter(is_delete=False, pk__in=pks).update(is_delete=True)
        except:
            return APIResponse(1, '数据有误')

        if rows:
            return APIResponse(0, '删除成功')
        return APIResponse(1, '删除失败')

        # 整体单改群改

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

        pk = kwargs.get('pk')
        if pk:  # 单改
            try:
                # 与增的区别在于，需要明确被修改的对象，交给序列化类
                car_instance = models.Car.objects.get(is_delete=False, pk=pk)
            except:
                return Response({'detail': 'pk error'}, status=400)
            car_ser = serializers.CarModelSerializer(instance=car_instance, data=request.data)
            car_ser.is_valid(raise_exception=True)
            car_obj = car_ser.save()
            return APIResponse(request=serializers.CarModelSerializer(car_obj).data)
        else:  # 群改

            request_data = request.data
            try:
                pks = []
                for dic in request_data:
                    pk = dic.pop('pk')  # 解决分析1，没有pk pop方法就会抛异常
                    pks.append(pk)
                car_query = models.Car.objects.filter(is_delete=False, pk__in=pks).all()
                if len(pks) != len(car_query):
                    raise Exception('pk对应的数据不存在')
            except Exception as e:
                return Response({'detail': '%s' % e}, status=400)

            car_ser = serializers.CarModelSerializer(instance=car_query, data=request.data, many=True)
            car_ser.is_valid(raise_exception=True)
            car_list = car_ser.save()
            return APIResponse(request=serializers.CarModelSerializer(car_list, many=True).data)

        # 局部单改群改

    def patch(self, request, *args, **kwargs):
        pk = kwargs.get('pk')
        if pk:  # 单改
            try:
                # 与增的区别在于，需要明确被修改的对象，交给序列化类
                car_instance = models.Car.objects.get(is_delete=False, pk=pk)
            except:
                return Response({'detail': 'pk error'}, status=400)

            car_ser = serializers.CarModelSerializer(instance=car_instance, data=request.data, partial=True,
                                                       context={'request': request})
            car_ser.is_valid(raise_exception=True)
            car_obj = car_ser.save()
            return APIResponse(request=serializers.CarModelSerializer(car_obj).data)
        else:  # 群改

            request_data = request.data
            try:
                pks = []
                for dic in request_data:
                    pk = dic.pop('pk')  # 解决分析1，没有pk pop方法就会抛异常
                    pks.append(pk)
                car_query = models.Car.objects.filter(is_delete=False, pk__in=pks).all()
                if len(pks) != len(car_query):
                    raise Exception('pk对应的数据不存在')
            except Exception as e:
                return Response({'detail': '%s' % e}, status=400)

            car_ser = serializers.CarModelSerializer(instance=car_query, data=request.data, many=True, partial=True)
            car_ser.is_valid(raise_exception=True)
            car_list = car_ser.save()
            return APIResponse(request=serializers.CarModelSerializer(car_list, many=True).data)

序列化

from rest_framework import serializers
from . import models
# 多表操作
class CarListSerializer(serializers.ListSerializer):
    # 自定义的群增辅助类，没有必要重写create方法
    def create(self, validated_data):
        return super().create(validated_data)
    #自定义的群改辅助类
    def update(self, instance_list, validated_data_list):
        return [
            self.child.update(instance_list[index], attrs) for index, attrs in enumerate(validated_data_list)
        ]

class CarModelSerializer(serializers.ModelSerializer):
    class Meta:
        list_serializer_class = CarListSerializer

        model = models.Car
        fields = ['name', 'price', 'merchant', 'sponsor', 'merchant_info', 'sponsor_list']
        extra_kwargs = {
            'merchant': {
                'write_only': True
            },
            'sponsor': {
                'write_only': True
            }
        }

    # 验证视图类是否将request请求参数通过context传入
    def validate(self, attrs):
        print('传入的request: %s' % self.context.get('request'))
        return attrs

response二次封装

from rest_framework.response import Response


class APIResponse(Response):
    def __init__(self, status=0, msg='ok', results=None, http_status=None,
                 headers=None, exception=False, content_type=None, **kwargs):
        # 将status、msg、results、kwargs格式化成data
        data = {
            'status': status,
            'msg': msg,
        }
        # results只要是不为空都是数据：False 0 '' 都是数据=>条件不能写if results
        if results is not None:
            data['results'] = results
        # 将kwargs中额外的k-v数据添加到data中
        data.update(**kwargs)
        super().__init__(data=data, status=http_status, headers=headers, exception=exception, content_type=content_type)