1、更改dev配置
因为前端可能携带cookie，为了保证跨域请求中，允许后端使用cookie，确保在配置文件有如下设置
CORS_ALLOW_CREDENTIALS = True
2、创建购物车应用carts（apps/）
python ../../manage.py startapp carts
3、在dev中注册应用和配置redis数据库
INSTALLED_APPS = [
'carts.apps.CartsConfig',
]
# 配置redis数据库
CACHES = {
"carts": {
"BACKEND": "django_redis.cache.RedisCache",
"LOCATION": "redis://127.0.0.1:6379/4",
"OPTIONS": {
"CLIENT_CLASS": "django_redis.client.DefaultClient",
}
},
}
4、在serializers中创建序列化器CartsSerialziers
from rest_framework import serializers
from goods.models import SKU
class CartsSerialziers(serializers.Serializer):
sku_id = serializers.IntegerField(min_value=1)
count = serializers.IntegerField(min_value=1)
selected = serializers.BooleanField(default=True)
def validate(self, attrs):
# 判断sku——id商品是否存在
try:
sku = SKU.objects.get(id=attrs['sku_id'])
except:
raise serializers.ValidationError('商品不存在')
# 判断库存
if attrs['count'] > sku.stock:
raise serializers.ValidationError('商品库存不足')
return attrs
class CartListSeriazlier(serializers.ModelSerializer):
count = serializers.IntegerField(min_value=True,read_only=True)
selected = serializers.BooleanField(default=True,read_only=True)
class Meta:
model=SKU
fields="__all__"
class CartsDeleteSerialziers(serializers.Serializer):
sku_id = serializers.IntegerField(min_value=True)
class CartsSelectedSerialziers(serializers.Serializer):
selected = serializers.BooleanField(default=True)
5、在views中创建CartsView类，定义post方法。
from django.shortcuts import render
from rest_framework.response import Response
from rest_framework.views import APIView
from django_redis import get_redis_connection
# Create your views here.
from carts.serializers import CartsSerialziers, CartListSeriazlier, CartsDeleteSerialziers, CartsSelectedSerialziers
import pickle, base64
from goods.models import SKU
class CartsView(APIView):
"""
购物车数据的增删改查
"""
def perform_authentication(self, request):
# 不再调用post方法之前进行验证
# request.user
pass
def post(self, request):
# 1、获取数据
data = request.data
# 2、验证数据
ser = CartsSerialziers(data=data)
ser.is_valid()
print(ser.errors)
# 获取验证后数据
sku_id = ser.validated_data['sku_id']
count = ser.validated_data['count']
selected = ser.validated_data['selected']
# 3、判断用户登录状态
try:
user = request.user
except:
user = None
if user is not None:
# 4、已登陆 保存redis
# 1、建立连接
conn = get_redis_connection('carts')
# 2、写入hash sku - id和cout
conn.hincrby('cart_%s' % user.id, sku_id, count)
# 3、写入set
if selected:
conn.sadd('cart_selected_%s' % user.id, sku_id)
# 4、结果返回
return Response({'message': 'ok'})
else:
# 5、未登录 保存cookie
response = Response({'message': 'ok'})
# 1、先获取cookie，判断原来是否写入过cookie
cart_cookie = request.COOKIES.get('cart_cookie', None)
if cart_cookie:
# 2、写入过。解密.cart = {10: {‘count’:2, selected: True}
cart = pickle.loads(base64.b64decode(cart_cookie))
else:
# 3、未写入过cart = {}
cart = {}
# 4、判断sku - id是否存在 累加
sku = cart.get(sku_id)
if sku:
count += int(sku['count'])
# 5、写入新数据
cart[sku_id] = {
'count': count,
'selected': selected
}
# 6、加密操作
cart_cookie = base64.b64encode(pickle.dumps(cart)).decode()
# 7、写入cookie
response.set_cookie('cart_cookie', cart_cookie, max_age=60 * 60 * 24)
# 8、结果返回
return response
def get(self, request):
# 1、判断用户登录状态
try:
user = request.user
except:
user = None
if user is not None:
# 2、已登陆 保存redis
# 1、建立连接
conn = get_redis_connection('carts')
# 2、获取hash sku - id和cout
sku_id_count=conn.hgetall('cart_%s' % user.id)
# 3、获取set
selecteds=conn.smembers('cart_selected_%s' % user.id)
# 4\构建字典数据
cart={}
for sku_id,count in sku_id_count.items():
cart[int(sku_id)]={
'count':int(count),
'selected':sku_id in selecteds
}
else:
# 3、未登录 保存cookie
# 1、先获取cookie，判断原来是否写入过cookie
cart_cookie = request.COOKIES.get('cart_cookie', None)
if cart_cookie:
# 2、写入过。解密.cart = {10: {‘count’:2, selected: True}
cart = pickle.loads(base64.b64decode(cart_cookie))
else:
# 3、未写入过cart = {}
cart = {}
# 4、获取字典中的sku_id
sku_ids=cart.keys()
# 5、根据sku_id, 查询商品数据对象
skus=SKU.objects.filter(id__in=sku_ids)
for sku in skus:
sku.count=cart[sku.id]['count']
sku.selected=cart[sku.id]['selected']
# 6、序列化返回数据对象
ser=CartListSeriazlier(skus,many=True)
return Response(ser.data)
def put(self, request):
# 1、获取数据
data = request.data
# 2、验证数据
ser = CartsSerialziers(data=data)
ser.is_valid()
print(ser.errors)
# 获取验证后数据
sku_id = ser.validated_data['sku_id']
count = ser.validated_data['count']
selected = ser.validated_data['selected']
# 3、判断用户登录状态
try:
user = request.user
except:
user = None
if user is not None:
# 4、已登陆 保存redis
# 1、建立连接
conn = get_redis_connection('carts')
# 2、更新hash sku - id和cout
conn.hset('cart_%s' % user.id, sku_id, count)
# 3、更新set
if selected:
conn.sadd('cart_selected_%s' % user.id, sku_id)
else:
conn.srem('cart_selected_%s' % user.id, sku_id)
# 4、结果返回
return Response({'count': count})
else:
# 5、未登录 保存cookie
response = Response({'count': count})
# 1、先获取cookie，判断原来是否写入过cookie
cart_cookie = request.COOKIES.get('cart_cookie', None)
if cart_cookie:
# 2、写入过。解密.cart = {10: {‘count’:2, selected: True}
cart = pickle.loads(base64.b64decode(cart_cookie))
else:
# 3、未写入过cart = {}
cart = {}
# 4、写入新数据
cart[sku_id] = {
'count': count,
'selected': selected
}
# 5、加密操作
cart_cookie = base64.b64encode(pickle.dumps(cart)).decode()
# 6、写入cookie
response.set_cookie('cart_cookie', cart_cookie, max_age=60 * 60 * 24)
# 9、结果返回
return response
def delete(self, request):
# 1、获取数据
data = request.data
# 2、验证数据
ser = CartsDeleteSerialziers(data=data)
ser.is_valid()
print(ser.errors)
# 获取验证后数据
sku_id = ser.validated_data['sku_id']
# 3、判断用户登录状态
try:
user = request.user
except:
user = None
if user is not None:
# 4、已登陆 删除redis
# 1、建立连接
conn = get_redis_connection('carts')
# 2、删除hash sku - id和cout
conn.hdel('cart_%s' % user.id, sku_id)
# 3、删除set
conn.srem('cart_selected_%s' % user.id, sku_id)
# 4、结果返回
return Response({'message': 'ok'})
else:
# 5、未登录 保存cookie
response = Response({'message': 'ok'})
# 1、先获取cookie，判断原来是否写入过cookie
cart_cookie = request.COOKIES.get('cart_cookie', None)
if cart_cookie:
# 2、写入过。解密.cart = {10: {‘count’:2, selected: True}
cart = pickle.loads(base64.b64decode(cart_cookie))
# 3、删除数据
if sku_id in cart.keys():
del cart[sku_id]
# 4、加密操作
cart_cookie = base64.b64encode(pickle.dumps(cart)).decode()
# 5、写入cookie
response.set_cookie('cart_cookie', cart_cookie, max_age=60 * 60 * 24)
# 6、结果返回
return response
class CartsSelectedView(APIView):
def perform_authentication(self, request):
# 不再调用put方法之前进行验证
# request.user
pass
def put(self, request):
# 1、获取数据
data = request.data
# 2、验证数据
ser = CartsSelectedSerialziers(data=data)
ser.is_valid()
print(ser.errors)
# 获取验证后数据
selected = ser.validated_data['selected']
# 3、判断用户登录状态
try:
user = request.user
except:
user = None
if user is not None:
# 4、已登陆 保存redis
# 1、建立连接
conn = get_redis_connection('carts')
# 2、获取hash sku——id和cout
sku_id_count=conn.hgetall('cart_%s' % user.id) #{1:2}
sku_ids=sku_id_count.keys() #[1,2,3]
# 3、更新set
if selected:
conn.sadd('cart_selected_%s' % user.id,*sku_ids)
else:
conn.srem('cart_selected_%s' % user.id, *sku_ids)
# 4、结果返回
return Response({'selected': selected})
else:
# 5、未登录 保存cookie
response = Response({'selected': selected})
# 1、先获取cookie，判断原来是否写入过cookie
cart_cookie = request.COOKIES.get('cart_cookie', None)
if cart_cookie:
# 2、写入过。解密.cart = {10: {‘count’:2, selected: True}
cart = pickle.loads(base64.b64decode(cart_cookie))
# 3、更新所有数据
for sku_id,data in cart.items():
data['selected']=selected
# 4、加密操作
cart_cookie = base64.b64encode(pickle.dumps(cart)).decode()
# 5、写入cookie
response.set_cookie('cart_cookie', cart_cookie, max_age=60 * 60 * 24)
# 6、结果返回
return response
6、注册路由
- 主路由
from django.conf.urls import url,include
from django.contrib import admin
urlpatterns = [
url(r'^', include('carts.urls')),
]
- 子路由
from django.conf.urls import url
from django.contrib import admin
from . import views
urlpatterns = [
url(r'^cart/$', views.CartsView.as_view()),
url(r'^cart/selection/$', views.CartsSelectedView.as_view()),
]