一 基本功能
-添加购物车
-详见代码
-修改课程价格策略
-put或者patch
{"course_id": "1", "policy_id": "1"}
-查看购物车
-删除购物车数据
-购物车数据放在哪?
-放到redis中,不需要创建mysql的表来存储数据了
二 实现代码
2.1相关表单建立
from django.db import models
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes.fields import GenericForeignKey
from django.contrib.contenttypes.fields import GenericRelation
# Create your models here.
# class CourseType(models.Model):
class UserInfo(models.Model):
name = models.CharField(max_length=64)
pwd = models.CharField(max_length=32)
class Token(models.Model):
user = models.OneToOneField(to=UserInfo)
token = models.CharField(max_length=64)
class Category(models.Model):
nid = models.AutoField(primary_key=True)
name = models.CharField(max_length=64)
class Course(models.Model):
"""专题课程"""
# unique=True 唯一性约束
name = models.CharField(max_length=128, unique=True)
course_img = models.CharField(max_length=255)
brief = models.TextField(verbose_name="课程概述", max_length=2048)
level_choices = ((0, '初级'), (1, '中级'), (2, '高级'))
# 默认值为1 ,中级
level = models.SmallIntegerField(choices=level_choices, default=1)
pub_date = models.DateField(verbose_name="发布日期", blank=True, null=True)
period = models.PositiveIntegerField(verbose_name="建议学习周期(days)", default=7)
# help_text 在admin中显示的帮助信息
order = models.IntegerField("课程顺序", help_text="从上一个课程数字往后排")
status_choices = ((0, '上线'), (1, '下线'), (2, '预上线'))
status = models.SmallIntegerField(choices=status_choices, default=0)
# 用于GenericForeignKey反向查询，不会生成表字段，切勿删除
price_policy = GenericRelation("PricePolicy")
category = models.ForeignKey(to='Category',to_field='nid',null=True)
def __str__(self):
return self.name
class Meta:
verbose_name_plural = "专题课"
class CourseDetail(models.Model):
"""课程详情页内容"""
course = models.OneToOneField("Course", on_delete=models.CASCADE)
hours = models.IntegerField("课时")
# 课程的标语 口号
course_slogan = models.CharField(max_length=125, blank=True, null=True)
# video_brief_link = models.CharField(verbose_name='课程介绍', max_length=255, blank=True, null=True)
# why_study = models.TextField(verbose_name="为什么学习这门课程")
# what_to_study_brief = models.TextField(verbose_name="我将学到哪些内容")
# career_improvement = models.TextField(verbose_name="此项目如何有助于我的职业生涯")
# prerequisite = models.TextField(verbose_name="课程先修要求", max_length=1024)
# 推荐课程
# related_name 基于对象的反向查询,用于替换表名小写_set
recommend_courses = models.ManyToManyField("Course", related_name="recommend_by", blank=True)
teachers = models.ManyToManyField("Teacher", verbose_name="课程讲师")
def __str__(self):
return "%s" % self.course
class Meta:
verbose_name_plural = "课程详细"
class PricePolicy(models.Model):
"""价格与有课程效期表"""
content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE) # 关联course or degree_course
object_id = models.PositiveIntegerField()
content_object = GenericForeignKey('content_type', 'object_id')
# course = models.ForeignKey("Course")
valid_period_choices = ((1, '1天'), (3, '3天'),
(7, '1周'), (14, '2周'),
(30, '1个月'),
(60, '2个月'),
(90, '3个月'),
(180, '6个月'), (210, '12个月'),
(540, '18个月'), (720, '24个月'),
)
valid_period = models.SmallIntegerField(choices=valid_period_choices)
price = models.FloatField()
class Meta:
unique_together = ("content_type", 'object_id', "valid_period")
verbose_name_plural = "价格策略"
def __str__(self):
return "%s(%s)%s" % (self.content_object, self.get_valid_period_display(), self.price)
class Teacher(models.Model):
"""讲师、导师表"""
name = models.CharField(max_length=32)
image = models.CharField(max_length=128)
brief = models.TextField(max_length=1024)
def __str__(self):
return self.name
class Meta:
verbose_name_plural = "讲师"
2.2自定义response与Exception信息
class MyResponse():
def __init__(self):
self.status = 100
self.msg = None
@property
def get_dic(self):
return self.__dict__
class CommonException(Exception):
def __init__(self,status,msg):
self.status =status
self.msg = msg
2.3登录认证组件
from rest_framework.authentication import BaseAuthentication
from api import models
from rest_framework.exceptions import AuthenticationFailed
class LoginAuth(BaseAuthentication):
def authenticate(self, request):
token = request.GET.get('token')
ret = models.UserToken.objects.filter(token=token).first()
if ret:
# 有值说明认证通过,返回两个值
return ret.user, ret
else:
raise AuthenticationFailed('认证失败,没有登录')
2.4views
from rest_framework.views import APIView
from rest_framework.response import Response
from api import models
from api.utils.commonUtils import MyResponse
from rest_framework.viewsets import ViewSetMixin
from django.core.exceptions import ObjectDoesNotExist
from django.conf import settings
from api.utils.MyAuth import LoginAuth
from api.utils.commonUtils import CommonException
from django_redis import get_redis_connection
import json
# 需要登录之后才能操作,写一个认证组件
class ShoppingCart(APIView):
authentication_classes = [LoginAuth]
conn = get_redis_connection()
def post(self, request, *args, **kwargs):
response = MyResponse()
# 课程id,价格策略id
# {"course_id": "1", "policy_id": "1"}
# 放到redis中key值 shoppingcart_userid_courseid
# 0 取出课程id,价格策略id
course_id = str(request.data.get('course_id'))
policy_id = str(request.data.get('policy_id'))
# 1 校验课程是否合法
try:
course = models.Course.objects.get(pk=course_id)
# 2 获取所有价格策略(通过课程拿出所有价格策略)
policy_price_all = course.price_policy.all()
# 3 从redis中取出当前登录用户的购物车
shopping_byte = self.conn.get('shoppingcart_%s' % request.user.pk)
if shopping_byte:
shopping_cart = json.loads(shopping_byte)
else:
shopping_cart = {}
# 循环构造出价格策略大字典
policy = {}
for policy_price in policy_price_all:
'''
{
"period":3,
"period_display":"3天",
"price":200
},
'''
policy_one = {
'period': policy_price.pk,
'period_display': policy_price.get_valid_period_display(),
'price': policy_price.price
}
policy[str(policy_price.pk)] = policy_one
# 判断价格策略是否合法,不再字典中,就不合法
if policy_id not in policy:
# 不合法
raise CommonException(102, '价格策略不合法,你不是人')
# 判断传入的课程id是否在购物车中
if course_id in shopping_cart:
# 更新一下默认价格策略
shopping_cart[course_id]['default_policy'] = policy_id
response.msg = '更新成功'
else:
shopping_course = {
'title': course.name,
'img': course.course_img,
'default_policy': policy_id,
'policy': policy
}
# 添加到购物车
shopping_cart[course_id] = shopping_course
response.msg = '添加成功'
# 写入redis
self.conn.set('shoppingcart_%s' % request.user.pk, json.dumps(shopping_cart))
except ObjectDoesNotExist as e:
response.status = 101
response.msg = '该课程不存在,你可能是爬虫'
except CommonException as e:
response.status = e.status
response.msg = e.msg
except Exception as e:
response.status = 400
response.msg = '未知错误'
print(str(e))
return Response(response.get_dic)
def put(self,request,*args,**kwargs):
response=MyResponse()
# 0 取出课程id,价格策略id
course_id = str(request.data.get('course_id'))
policy_id = str(request.data.get('policy_id'))
try:
shopping_byte = self.conn.get('shoppingcart_%s' % request.user.pk)
if shopping_byte:
shopping_cart = json.loads(shopping_byte)
else:
shopping_cart = {}
if course_id not in shopping_cart:
raise CommonException(102,'要修改的课程不存在')
course_detail=shopping_cart.get(course_id)
if policy_id not in course_detail['policy']:
raise CommonException(103, '价格策略不合法')
course_detail['default_policy']=policy_id
response.msg='修改成功'
self.conn.set('shoppingcart_%s' % request.user.pk, json.dumps(shopping_cart))
except ObjectDoesNotExist as e:
response.status = 101
response.msg = '该课程不存在,你可能是爬虫'
except CommonException as e:
response.status = e.status
response.msg = e.msg
except Exception as e:
response.status = 400
response.msg = '未知错误'
print(str(e))
return Response(response.get_dic)
def get(self,request,*args,**kwargs):
response=MyResponse()
try:
shopping_byte = self.conn.get('shoppingcart_%s' % request.user.pk)
if shopping_byte:
shopping_cart = json.loads(shopping_byte)
else:
shopping_cart = {}
response.data=shopping_cart
except Exception as e:
response.status = 400
response.msg = '未知错误'
print(str(e))
return Response(response.get_dic)
def delete(self, request, *args, **kwargs):
response=MyResponse()
course_id=request.data.get('course_id')
try:
shopping_byte = self.conn.get('shoppingcart_%s' % request.user.pk)
if shopping_byte:
shopping_cart = json.loads(shopping_byte)
else:
shopping_cart = {}
shopping_cart.pop(course_id,None)
self.conn.set('shoppingcart_%s' % request.user.pk, json.dumps(shopping_cart))
except Exception as e:
response.status = 400
response.msg = '未知错误'
print(str(e))
return Response(response.get_dic)
2.5redis配置
CACHES = {
"default": {
"BACKEND": "django_redis.cache.RedisCache",
"LOCATION": "redis://127.0.0.1:6379",
"OPTIONS": {
"CLIENT_CLASS": "django_redis.client.DefaultClient",
"CONNECTION_POOL_KWARGS": {"max_connections": 1000}
# "PASSWORD": "123",
}
}
}
