python笔记(前后端分离项目涉及知识，restframework(有跨域相关))

一、 serializers一些方法

serializers.ModelSerializer(serializerdate.py)

class CourseDetailModelSerializers(serializers.ModelSerializer):
    course = serializers.CharField(source='course.title')      # 对于一对一和一对多跨表查询
    courseImg = serializers.CharField(source='course.courseImg')
    leve = serializers.CharField(source='course.get_leve_display') # 拿取多选字段的中文
    chapters = serializers.SerializerMethodField()  # 对于manytomany字段
    recommend = serializers.SerializerMethodField()   # 对于反向查询
    class Meta:
        model = models.CourseDetail
        fields = ['why_study','slogon','course','slogon','recommend','courseImg','leve','chapters']
        # depth = 1
    def get_recommend(self,obj):#obj：就是CourseDetail这个对象
        queryset = obj.recommend_course.all()
        return [{"id":item.pk,"title":item.title} for item in queryset]
    def get_chapters(self,obj):
        queryset = obj.course.chapters_set.all()
        return [{"name":item.name,"num":item.num} for item in queryset]

views.py

queryset = models.Course.objects.all()
ser = serializerdate.CourseModelSerializers(instance=queryset,many=True)

二、 models,ORM一些方法

models.Token.objects.update_or_create(user=user,defaults={"token":uid})对于user用户有token就更新，没有就添加

contenttype
组件的作用：可以通过两个字段让表和N张表创建FK关系
表结构：
python笔记(前后端分离项目涉及知识，restframework(有跨域相关))

 	from django.db import models
 	from django.contrib.contenttypes.models import ContentType

 	from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation


 	class DegreeCourse(models.Model):
 		"""学位课程"""
 		name = models.CharField(max_length=128, unique=True)
 		course_img = models.CharField(max_length=255, verbose_name="缩略图")
 		brief = models.TextField(verbose_name="学位课程简介", )


 	class Course(models.Model):
 		"""专题课程"""
 		name = models.CharField(max_length=128, unique=True)
 		course_img = models.CharField(max_length=255)

 		# 不会在数据库生成列，只用于帮助你进行查询
 		policy_list = GenericRelation("PricePolicy")


 	class PricePolicy(models.Model):
 		"""价格与有课程效期表"""
 		content_type = models.ForeignKey(ContentType)  # 关联course or degree_course
 		object_id = models.PositiveIntegerField()

 		#不会在数据库生成列，只用于帮助你进行添加和查询
 		content_object = GenericForeignKey('content_type', 'object_id')
 		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()

使用：

在价格策略表中添加一条数据

  models.PricePolicy.objects.create(
 	     valid_period=7,
 	     price=6.6,
 	     content_type=ContentType.objects.get(model='course'),
 	     object_id=1
 	 )

  models.PricePolicy.objects.create(
      valid_period=14,
      price=9.9,
      content_object=models.Course.objects.get(id=1)
  )

根据某个价格策略对象，找到他对应的表和数据，如：管理课程名称

   price = models.PricePolicy.objects.get(id=2)
   print(price.content_object.name) # 自动帮你找到

找到某个课程关联的所有价格策略

   obj = models.Course.objects.get(id=1)
   for item in obj.policy_list.all():
       print(item.id,item.valid_period,item.price)

verbose_name

 verbose_name   的意思很简单，就是给你的模型类起一个更可读的名字一般定义为中文，我们：
 verbose_name = "学校"
 
 verbose_name_plural
 这个选项是指定，模型的复数形式是什么，比如：
 verbose_name_plural = "学校"
 如果不指定Django会自动在模型名称后加一个’s’
 help_text    admin模式下帮助文档

三、跨域（CORS方法）

MyMiddleWare.py

class CORSMiddleware(MiddlewareMixin):
    def process_response(self,request,response):

        # 允许所有域名来获取我的数据
        response['Access-Control-Allow-Origin'] = "*"
        if request.method == "OPTIONS":
            # 允许你携带
            response['Access-Control-Allow-Headers'] = "Content-Type"
            # 允许你发送DELETE,PUT,POST
            response['Access-Control-Allow-Methods'] = "DELETE,PUT,POST"
        return response

在setting.py的MIDDLEWARE中添加

'app01.MyMiddleWare.CORSMiddleware'

四、认证组件

Auth.py

class MircAuth(BaseAuthentication):
    def authenticate(self,request):
        token = request.query_params.get('token')
        obj = models.Token.objects.filter(token=token).first()
        if not obj:
            raise AuthenticationFailed({"code":1001,"error":"认证失败"})
        return (obj.user.username,obj)

views.py

class Micro(APIView):
    authentication_classes = [Auth.MircAuth]
    def get(self,request,*args,**kwargs):
       # print(request.auth)
       # print(request.user)
        ret = {"code":1000,"title":"微职位"}
        return Response(ret)

python笔记(前后端分离项目涉及知识，restframework(有跨域相关))

相关推荐