lf 前后端分离 (2) 课程数据获取,Serializer的返回

一.关于课程数据的返回

在进行前后端分离时,会通过def 进行前后端传值,

本质上遵循rest 网址规范  增删改查查 get,post,put,del get(\d+)

1.在从数据库获取数据后,进行def 发送ajax数据,

通过from rest_framework import serializers

快速获取数据,在 class CourseSerializer(serializers.ModelSerializer)中

level = serializers.CharField(source="get_level_display")为获取的一对多的关联数据库的具体字段,不加source会直接显示_id
 
在进行choice字段时,为了显示文字,采用

level = serializers.CharField(source="course.get_level_display")

在进行多对多字段时,需要自定义方法,遵循

recommend_coursesinfo = serializers.SerializerMethodField()
通过循环,所关联的全部字段,打印出要获取的值,注意,当字段函数与返回值同名时,会覆盖

 from django.shortcuts import render
 from rest_framework import serializers
 
 from app01.models import *
 
 class CourseSerializer(serializers.ModelSerializer):
     class Meta:
         model = Course
         fields = "__all__"
 
     level = serializers.CharField(source="get_level_display")
     coursedetail_id = serializers.CharField(source="coursedetail.pk")
 
 class CourseDetailSerializer(serializers.ModelSerializer):
     class Meta:
         model = CourseDetail
         fields = "__all__"
 
     name = serializers.CharField(source="course.name")
     prices = serializers.SerializerMethodField()
     brief = serializers.CharField(source="course.brief")
     study_all_time = serializers.StringRelatedField(source='hours')
     level = serializers.CharField(source="course.get_level_display")
     teacher = serializers.SerializerMethodField()
     is_online = serializers.CharField(source="course.get_status_display")
     recommend_coursesinfo = serializers.SerializerMethodField()
 
     def get_prices(self,instance):
         return [{"price": obj.price,
                  "valid_period": obj.valid_period,
                  "valid_period_text": obj.get_valid_period_display(),
                  "id": obj.pk,
                  }for obj in instance.course.price_policy.all()]
 
     def get_teacher(self, instance):
         return [{"name": obj.name,
                  "image": obj.image}for obj in instance.teachers.all()]
 
     def get_recommend_coursesinfo(self, instance):
         return [{"name": obj.name,
                  "pk": obj.pk} for obj in instance.recommend_courses.all()]

serializers

并且返回的数据需要与前端vue匹配,跨

 from django.shortcuts import render
 
 from app01 import models
 from app01.utils.auth import LoginAuth
 
 from rest_framework.response import Response
 from rest_framework.views import APIView
 
 from serializer.views import CourseSerializer, CourseDetailSerializer
 
 class CourseViews(APIView):
     authentication_classes = [LoginAuth]
 
     def get(self, request):
         course = models.Course.objects.all()
         data = CourseSerializer(course, many=True)
         res = {"error_no": 0, "data": data.data}
         return Response(res)
 
 class CourseDetailViews(APIView,):
 
     authentication_classes = [LoginAuth]
 
     def get(self, request, pk):
         coursedetail = models.CourseDetail.objects.get(pk=pk)
         data = CourseDetailSerializer(coursedetail, many=False)
         res = {"error_no": 0, "data": data.data}
         return Response(res)

course

其他详见