qhfl-3 Course模块

课程模块，包括免费课程以及专题课程两个，主要是课程的展示，点击课程进入课程详细页面

根据功能设计表结构

为了方便，每张表在数据库中添加了中文名

from django.db import models
from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation
from django.contrib.contenttypes.models import ContentType
# from shopping.models import OrderDetail,Coupon

# 注册admin 的时候 方便引入
__all__ = ["Category", "Course", "CourseDetail", "Teacher", "DegreeCourse", "CourseChapter",
           "CourseSection", "PricePolicy", "OftenAskedQuestion", "Comment", "Account", "CourseOutline"]

class Category(models.Model):
    """课程分类表"""
    title = models.CharField(max_length=32, unique=True, verbose_name="课程的分类")

    def __str__(self):
        return self.title

    class Meta:
        verbose_name = "01-课程分类表"
        db_table = verbose_name
        verbose_name_plural = verbose_name

class Course(models.Model):
    """课程表"""
    title = models.CharField(max_length=128, unique=True, verbose_name="课程的名称")
    course_img = models.ImageField(upload_to="course/%Y-%m", verbose_name='课程的图片')
    category = models.ForeignKey(to="Category", verbose_name="课程的分类", on_delete=None)

    COURSE_TYPE_CHOICES = ((0, "付费"), (1, "vip专享"), (2, "学位课程"),(3,"免费"))
    course_type = models.SmallIntegerField(choices=COURSE_TYPE_CHOICES)
    degree_course = models.ForeignKey(to="DegreeCourse", blank=True, null=True, help_text="如果是学位课程，必须关联学位表",
                                      on_delete=None)

    brief = models.CharField(verbose_name="课程简介", max_length=1024)
    level_choices = ((0, '初级'), (1, '中级'), (2, '高级'))
    level = models.SmallIntegerField(choices=level_choices, default=1)

    status_choices = ((0, '上线'), (1, '下线'), (2, '预上线'))
    status = models.SmallIntegerField(choices=status_choices, default=0)
    pub_date = models.DateField(verbose_name="发布日期", blank=True, null=True)

    order = models.IntegerField("课程顺序", help_text="从上一个课程数字往后排")
    study_num = models.IntegerField(verbose_name="学习人数", help_text="只要有人买课程，订单表加入数据的同时给这个字段+1")

    # order_details = GenericRelation("OrderDetail", related_query_name="course")
    # coupon = GenericRelation("Coupon")
    # 只用于反向查询不生成字段
    price_policy = GenericRelation("PricePolicy")
    often_ask_questions = GenericRelation("OftenAskedQuestion")
    course_comments = GenericRelation("Comment")

    def save(self, *args, **kwargs):
        if self.course_type == 2:
            if not self.degree_course:
                raise ValueError("学位课必须关联学位课程表")
        super(Course, self).save(*args, **kwargs)

    def __str__(self):
        return self.title

    class Meta:
        verbose_name = "02-课程表"
        db_table = verbose_name
        verbose_name_plural = verbose_name

class CourseDetail(models.Model):
    """课程详细表"""
    course = models.OneToOneField(to="Course", on_delete=None)
    hours = models.IntegerField(verbose_name="课时", default=7)
    course_slogan = models.CharField(max_length=125, blank=True, null=True, verbose_name="课程口号")
    video_brief_link = models.CharField(max_length=255, blank=True, null=True)
    summary = models.TextField(max_length=2048, verbose_name="课程概述")
    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)
    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 self.course.title

    class Meta:
        verbose_name = "03-课程详细表"
        db_table = verbose_name
        verbose_name_plural = verbose_name

class Teacher(models.Model):
    """讲师表"""
    name = models.CharField(max_length=32, verbose_name="讲师名字")
    brief = models.TextField(max_length=1024, verbose_name="讲师介绍")

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = "04-教师表"
        db_table = verbose_name
        verbose_name_plural = verbose_name

class DegreeCourse(models.Model):
    """
    字段大体跟课程表相同，哪些不同根据业务逻辑去区分
    """
    title = models.CharField(max_length=32, verbose_name="学位课程名字")

    def __str__(self):
        return self.title

    class Meta:
        verbose_name = "05-学位课程表"
        db_table = verbose_name
        verbose_name_plural = verbose_name

class CourseChapter(models.Model):
    """课程章节表"""
    course = models.ForeignKey(to="Course", related_name="course_chapters", on_delete=None)
    chapter = models.SmallIntegerField(default=1, verbose_name="第几章")
    title = models.CharField(max_length=32, verbose_name="课程章节名称")

    def __str__(self):
        return self.title

    class Meta:
        verbose_name = "06-课程章节表"
        db_table = verbose_name
        verbose_name_plural = verbose_name
        unique_together = ("course", "chapter")

class CourseSection(models.Model):
    """课时表"""

    chapter = models.ForeignKey(to="CourseChapter", related_name="course_sections",verbose_name="self.chapter.course.title", on_delete=None)
    title = models.CharField(max_length=32, verbose_name="课时")
    section_order = models.SmallIntegerField(verbose_name="课时排序", help_text="建议每个课时之间空1至2个值，以备后续插入课时")
    section_type_choices = ((0, '文档'), (1, '练习'), (2, '视频'))
    free_trail = models.BooleanField("是否可试看", default=False)
    section_type = models.SmallIntegerField(default=2, choices=section_type_choices)
    section_link = models.CharField(max_length=255, blank=True, null=True, help_text="若是video，填vid,若是文档，填link")

    def course_chapter(self):
        return self.chapter.chapter

    def course_name(self):
        return self.chapter.course.title

    def __str__(self):
        return "%s-%s-%s课时" % (self.chapter.course,self.chapter, self.title)

    class Meta:
        verbose_name = "07-课程课时表"
        db_table = verbose_name
        verbose_name_plural = verbose_name
        unique_together = ('chapter', 'section_link')

class PricePolicy(models.Model):
    """价格策略表"""
    content_type = models.ForeignKey(ContentType, on_delete=None)  # 关联course or degree_course
    object_id = models.PositiveIntegerField()
    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'),
                            (120, '4个月'),
                            (180, '6个月'), (210, '12个月'),
                            (540, '18个月'), (720, '24个月'),
                            (722, '24个月'), (723, '24个月'),
                            )
    valid_period = models.SmallIntegerField(choices=valid_period_choices)
    price = models.FloatField()

    def __str__(self):
        return "%s(%s)%s" % (self.content_object, self.get_valid_period_display(), self.price)

    class Meta:
        verbose_name = "08-价格策略表"
        db_table = verbose_name
        verbose_name_plural = verbose_name
        unique_together = ("content_type", 'object_id', "valid_period")

class OftenAskedQuestion(models.Model):
    """常见问题"""
    content_type = models.ForeignKey(ContentType, on_delete=None)  # 关联course or degree_course
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id')

    question = models.CharField(max_length=255)
    answer = models.TextField(max_length=1024)

    def __str__(self):
        return "%s-%s" % (self.content_object, self.question)

    class Meta:
        verbose_name = "09-常见问题表"
        db_table = verbose_name
        verbose_name_plural = verbose_name
        unique_together = ('content_type', 'object_id', 'question')

class Comment(models.Model):
    """通用的评论表"""
    content_type = models.ForeignKey(ContentType, blank=True, null=True, on_delete=None)
    object_id = models.PositiveIntegerField(blank=True, null=True)
    content_object = GenericForeignKey('content_type', 'object_id')

    content = models.TextField(max_length=1024, verbose_name="评论内容")
    account = models.ForeignKey("Account", verbose_name="会员名", on_delete=None)
    date = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return self.content

    class Meta:
        verbose_name = "10-评价表"
        db_table = verbose_name
        verbose_name_plural = verbose_name

class Account(models.Model):
    username = models.CharField(max_length=32, verbose_name="用户姓名")
    pwd = models.CharField(max_length=32, verbose_name="密文密码")
    # head_img = models.CharField(max_length=256, default='/static/frontend/head_portrait/logo@2x.png',
    #                             verbose_name="个人头像")
    balance = models.IntegerField(verbose_name="贝里余额", default=0)

    def __str__(self):
        return self.username

    class Meta:
        verbose_name = "11-用户表"
        db_table = verbose_name
        verbose_name_plural = verbose_name

class CourseOutline(models.Model):
    """
    课程大纲
    跟课程详情外键关联，而不是直接跟课程，提高查询
    """
    course_detail = models.ForeignKey(to="CourseDetail", related_name="course_outline", on_delete=None)
    title = models.CharField(max_length=128)
    order = models.PositiveSmallIntegerField(default=1)
    # 前端显示顺序

    content = models.TextField("内容", max_length=2048)

    def __str__(self):
        return "%s" % self.title

    class Meta:
        verbose_name = "12-课程大纲表"  #
        db_table = verbose_name                         # 线上运行时不要写db_table
        verbose_name_plural = verbose_name
        unique_together = ('course_detail', 'title')  # 一个课程详情只有一个大纲

Course/models.py

不要忘了注册到admin

from . import models
for table in models.__all__:
    admin.site.register(getattr(models, table))

接口

对于课程这个模块，所有的功能都是展示，基于数据展示的，我们通常称为数据接口

这种接口对于我们来说是最简单的，从数据库拿数据，然后进行展示

需要的接口

　　-- 课程页面  课程所有分类

　　　　　　　 展示课程介绍的接口

　　-- 点击课程进入课程详情页面，详情页面的数据接口

　　-- 详情页面下的子路由对应子组件的数据接口

　　　　 课程章节课时

　　　　 课程的评论

　　　　 课程的常见问题

数据接口，都是读取数据库，序列化数据，返回

父路由分发
path('api/course/', include("Course.urls")),

课程分类接口

from rest_framework import serializers
from . import models

class CategorySerializer(serializers.ModelSerializer):
    class Meta:
        model = models.Category
        fields = "__all__"

class CategoryView(APIView):
    def get(self, request):
        # 通过ORM操作获取所有分类数据
        queryset = models.Category.objects.all()
        # 利用序列化器去序列化我们的数据
        ser_obj = CategorySerializer(queryset, many=True)
        # 返回
        return Response(ser_obj.data)

课程详情接口

CourseDetailSerializer

path('detail/<int:pk>', CourseDetailView.as_view()),

class CourseDetailView(APIView):
    def get(self, request, pk):
        # 根据pk获取到课程详情对象
        course_detail_obj = models.CourseDetail.objects.filter(course__id=pk).first()
        if not course_detail_obj:
            return Response({"code": 1001, "error": "查询的课程详情不存在"})
        # 序列化课程详情
        ser_obj = CourseDetailSerializer(course_detail_obj)
        # 返回
        return Response(ser_obj.data)

课程章节接口

CourseChapterSerializer

class CourseChapterView(APIView):
    def get(self, request, pk):
        # ["第一章": {课时一， 课时二}]
        queryset = models.CourseChapter.objects.filter(course_id=pk).all().order_by("chapter")
        # 序列化章节对象
        ser_obj = CourseChapterSerializer(queryset, many=True)
        # 返回
        return Response(ser_obj.data)

评论以及常见问题接口

class CourseCommentSerializer(serializers.ModelSerializer):
    account = serializers.CharField(source="account.username")

    class Meta:
        model = models.Comment
        fields = ["id", "account", "content", "date"]

class QuestionSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.OftenAskedQuestion
        fields = ["id", "question", "answer"]

class CourseCommentView(APIView):
    def get(self, request, pk):
        # 通过课程id找到课程所有的评论
        queryset = models.Course.objects.filter(id=pk).first().course_comments.all()
        # 序列化
        ser_obj = CourseCommentSerializer(queryset, many=True)
        # 返回
        return Response(ser_obj.data)

class QuestionView(APIView):
    def get(self, request, pk):
        queryset = models.Course.objects.filter(id=pk).first().often_ask_questions.all()
        ser_obj = QuestionSerializer(queryset, many=True)
        return Response(ser_obj.data)

from django.urls import path
from .views import CategoryView, CourseView, CourseDetailView, CourseChapterView, CourseCommentView, QuestionView
from .video_view import PolyvView

urlpatterns = [
    # 课程分类
    path('category', CategoryView.as_view()),

    # 课程
    path('list', CourseView.as_view()),

    #               课程id
    path('detail/<int:pk>', CourseDetailView.as_view()),

    # 课程的章节接口  课程id
    path('chapter/<int:pk>', CourseChapterView.as_view()),

    #  评论         课程id
    path('comment/<int:pk>', CourseCommentView.as_view()),

    path('question/<int:pk>', QuestionView.as_view()),

    path('polyv', PolyvView.as_view()),

]

Course/urls.py

from rest_framework import serializers
from . import models

class CategorySerializer(serializers.ModelSerializer):
    class Meta:
        model = models.Category
        fields = "__all__"

class CourseSerializer(serializers.ModelSerializer):
    level = serializers.CharField(source="get_level_display")  # 直接将选项的数字，转换成了可显示的字符
    price = serializers.SerializerMethodField()

    def get_price(self, obj):
        print(obj.price_policy.all())

        return obj.price_policy.all().order_by("price").first().price

    class Meta:
        model = models.Course
        fields = ["id", "title", "course_img", "brief", "level", "study_num", "price"]

class CourseDetailSerializer(serializers.ModelSerializer):
    level = serializers.CharField(source="course.get_level_display") # level 是选项时 get_xx_display 直接拿到选项的值
    study_num = serializers.IntegerField(source="course.study_num")
    recommend_courses = serializers.SerializerMethodField()  # 涉及到跨表，用
    teachers = serializers.SerializerMethodField()
    price_policy = serializers.SerializerMethodField()
    course_outline = serializers.SerializerMethodField()

    def get_course_outline(self, obj): # obj是课程对象
        return [{"id": outline.id, "title": outline.title, "content": outline.content} for outline in
                obj.course_outline.all().order_by("order")]

    def get_price_policy(self, obj):
        return [{"id": price.id, "valid_price_display": price.get_valid_period_display(), "price": price.price} for
                price in obj.course.price_policy.all()]

    def get_teachers(self, obj):
        return [{"id": teacher.id, "name": teacher.name} for teacher in obj.teachers.all()]

    def get_recommend_courses(self, obj):
        return [{"id": course.id, "title": course.title} for course in obj.recommend_courses.all()]

    class Meta:
        model = models.CourseDetail
        fields = ["id", "hours", "summary", "level", "study_num", "recommend_courses", "teachers",
                  "price_policy", "course_outline"]

class CourseChapterSerializer(serializers.ModelSerializer):
    sections = serializers.SerializerMethodField()

    def get_sections(self, obj):
        return [{"id": section.id, "title": section.title, "free_trail": section.free_trail} for section in
                obj.course_sections.all().order_by("section_order")]

    class Meta:
        model = models.CourseChapter
        fields = ["id", "title", "sections"]

class CourseCommentSerializer(serializers.ModelSerializer):
    account = serializers.CharField(source="account.username")

    class Meta:
        model = models.Comment
        fields = ["id", "account", "content", "date"]

class QuestionSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.OftenAskedQuestion
        fields = ["id", "question", "answer"]

Course/serializers.py

from rest_framework.views import APIView
from rest_framework.response import Response
from . import models
from .serializers import CategorySerializer, CourseSerializer, CourseDetailSerializer, CourseChapterSerializer
from .serializers import CourseCommentSerializer, QuestionSerializer

class CategoryView(APIView):
    def get(self, request):
        # 通过ORM操作获取所有分类数据
        queryset = models.Category.objects.all()
        # 利用序列化器去序列化我们的数据
        ser_obj = CategorySerializer(queryset, many=True)
        # 返回
        return Response(ser_obj.data)

class CourseView(APIView):
    def get(self, request):
        # 获取过滤条件中的分类ID
        category_id = request.query_params.get("category", 0)
        # 根据分类获取课程
        if category_id == 0:
            queryset = models.Course.objects.all().order_by("order")
        else:
            queryset = models.Course.objects.filter(category_id=category_id).all().order_by("order")
        # 序列化课程数据
        ser_obj = CourseSerializer(queryset, many=True)
        # 返回
        return Response(ser_obj.data)

class CourseDetailView(APIView):
    def get(self, request, pk):
        # 根据pk获取到课程详情对象
        course_detail_obj = models.CourseDetail.objects.filter(course__id=pk).first()
        if not course_detail_obj:
            return Response({"code": 1001, "error": "查询的课程详情不存在"})
        # 序列化课程详情
        ser_obj = CourseDetailSerializer(course_detail_obj)
        # 返回
        return Response(ser_obj.data)

class CourseChapterView(APIView):
    def get(self, request, pk):
        # ["第一章": {课时一， 课时二}]
        queryset = models.CourseChapter.objects.filter(course_id=pk).all().order_by("chapter")
        # 序列化章节对象
        ser_obj = CourseChapterSerializer(queryset, many=True)
        # 返回
        return Response(ser_obj.data)

class CourseCommentView(APIView):
    def get(self, request, pk):
        # 通过课程id找到课程所有的评论
        queryset = models.Course.objects.filter(id=pk).first().course_comments.all()
        # 序列化
        ser_obj = CourseCommentSerializer(queryset, many=True)
        # 返回
        return Response(ser_obj.data)

class QuestionView(APIView):
    def get(self, request, pk):
        queryset = models.Course.objects.filter(id=pk).first().often_ask_questions.all()
        ser_obj = QuestionSerializer(queryset, many=True)
        return Response(ser_obj.data)

Course/views.py

class CourseCategoryView(generics.ListAPIView):
    queryset = Category.objects.all()
    serializer_class = CourseCategorySerializer
    """课程分类接口"""

    # def get(self, request):
    #     queryset = Category.objects.all()
    #     ser_obj = CourseCategorySerializer(queryset, many=True)
    #     return Response(ser_obj.data)

class CourseChapterView(generics.RetrieveAPIView):
    queryset = CourseChapter.objects.all()
    serializer_class = CourseChapterSerializer
    # 指定过滤的类 用排序的过滤类
    filter_backends = (filters.OrderingFilter,)
    # 排序的字段
    ordering = ("chapter",)

    # def get(self, request, pk):
    #     # 首先我们要清楚数据结构
    #     # 我们要的是[章节一：{课时，课时2}]
    #     queryset = CourseChapter.objects.filter(course_id=pk).order_by("chapter")
    #     ser_obj = CourseChapterSerializer(queryset, many=True)
    #     return Response(ser_obj.data)

升级版视图的示例

Course/views.py 优化

Django的MEDIA配置

# settings.py

STATIC_URL = '/static/'
# Media配置
MEDIA_URL = "media/"
MEDIA_ROOT = os.path.join(BASE_DIR, "media")

# urls.py

from django.conf.urls import url, include
from django.contrib import admin
from django.views.static import serve
from new_luffy import settings

# media路径配置
re_path('media/(?P<path>.*)', serve, {'document_root': settings.MEDIA_ROOT})

上传的图片，数据库存的是路径地址，前端向后端的media路径发送请求。

线上环境时可以将 MEDIA_ROOT 存放到nginx的静态资源文件夹下面