day83

今日内容

rest_framework序列化

首先序列化需要对写一个类继承serializers.Serializer

方式一：在models的publish写一个__str__方法返回出版社名字

publish = serializers.CharField()

方式二：可以用source指定一个models中的方法

publish = serializers.CharField(source='publish.test')

方式三：直接用publish.他的字段名

publish = serializers.CharField(source='publish.name')

'''
class author_serializers(serializers.Serializer):
    name = serializers.CharField()
    age = serializers.CharField()

class Books_serializers(serializers.Serializer):
    xxx = serializers.CharField(source='name')
    yyy = serializers.CharField(source='price')
    # 方式一：在models的publish写一个__str__方法返回出版社名字
    # publish = serializers.CharField()
    # 方式二: 可以用source指定一个models中的方法
    # publish = serializers.CharField(source='publish.test')
    # 方式三：直接用publish.他的字段名
    # publish = serializers.CharField(source='publish.name')
    # SerializerMethodField可以指定一个方法，该方法需要时get_该字段名

    publish = serializers.SerializerMethodField()
    def get_publish(self, obj):
        dic = {'name': obj.publish.name, 'price': obj.publish.email}
        return dic

    # 可以继续使用序列化
    authors = serializers.SerializerMethodField()

    # def get_authors(self, obj):
        author = obj.authors.all()
        pub = author_serializers(author, many=True)
        return pub.data
'''

class author_serializers(serializers.Serializer):
    name = serializers.CharField()
    age = serializers.CharField()

class Books_serializers(serializers.ModelSerializer):
    class Meta:
        model = models.Book
        # 查询所有字段
        # fields = '__all__'
        # 查询列表中的字段
        fields = ['nid','name']
        # 除了这几个字段不要，查询其余字段
        # exclude = ['publish', 'authors']
        # 指定查询深度
        # depth = 1
    # publish = serializers.CharField(source='publish.name')
    # authors = serializers.SerializerMethodField()
    # def get_authors(self, obj):
    #     authors = obj.authors.all()
    #     Authors = author_serializers(authors, many=True)
    #     return Authors.data

视图函数：

class Books(APIView):
    def get(self, request):
        db_books = models.Book.objects.all()
        BOOKS = books(db_books, many=True)
        return JsonResponse(BOOKS.data, safe=False)

    def delete(self, request):
        id = request.query_params.get('id')
        models.Book.objects.filter(pk=id).delete()
        dic = {'status': 100, 'msg': '删除成功'}
        return JsonResponse(dic)

    def put(self, request):
        id = request.query_params.get('id')
        name = request.data.get('name')
        price = request.data.get('price')
        models.Book.objects.filter(pk=id).update(name=name, price=price)
        dic = {'status': 100, 'msg': '修改成功'}
        return JsonResponse(dic, safe=False)

    def post(self, request):
        p_name = request.data.get('name')
        p_price = request.data.get('price')
        p_publish = request.data.get('publish')
        p_authors = request.data.get('authors')
        book = models.Book.objects.create(name=p_name, price=p_price, publish_id=p_publish)
        p_authors = p_authors.split(',')
        for p_author in p_authors:
            author = models.Author.objects.filter(pk=p_author).first()
            print(author)
            book.authors.add(author)
        print(book)
        ret = books(book, many=False)
        return JsonResponse(ret.data, safe=False)

HyperlinkedIdentityField(用的很少)

　　-1 publish = serializers.HyperlinkedIdentityField(view_name='ttt',lookup_field='publish_id',lookup_url_kwarg='pky')
  　　-2 view_name:路由的别名,lookup_field:根据表的哪个字段,来拼路径,lookup_url_kwarg:反向解析有名分组的名字
  　　-3 写路由:url(r'^publish/(?P<pky>\d+)', views.Publish.as_view(),name='ttt'),
  　　-4 实例化序列化类的时候,需要把request对象传过去
   　　　　book_ser=BookSerializer(ret,many=True,context={'request': request})

设置：
class book_serializers(serializers.ModelSerializer):
    class Meta:
        model = models.Book
        fields = '__all__'

    url = serializers.HyperlinkedIdentityField(source='name', view_name='book', lookup_field='nid',
                                               lookup_url_kwarg='pk')
    # 该设置与form校验类似，都可设置一些参数（max_length，error_messages）
    name = serializers.CharField(max_length=20, error_messages={'required': '必填', 'max_length': '太长'})
    authors = serializers.CharField(required=False)
视图函数使用：
class BOOK(APIView):
    def get(self, request, *args, **kwargs):
        books = models.Book.objects.all()
        bs = SER.book_serializers(books, many=True, context={'request': request})
        return JsonResponse(bs.data, safe=False)

序列化组件的数据校验

　　　　-类比forms组件
  　　　　-字段是否必填,通过required,来控制 authors=serializers.CharField(required=False)
 　　　　 -数据校验,生成一个序列化类的对象
   　　　　　　-对象.is_valid()
  　　　　-新增数据:
  　　　　　　 -对象.save()
  　　　　-修改数据:
   　　　　　　-在生成对象的时候,需要传instanse=查询出来的对象
   　　　　　　-对象.save()

视图函数中使用：

设置时：

校验中的局部、全局钩子

    def validate_name(self, value):
        user = models.UserInfo.objects.filter(name=value).first()
        if user:
            raise ValidationError('用户名存在')
        else:
            return value

    def validate(self, attrs):
        name = attrs.get('name')
        pwd = attrs.get('pwd')
        if name and pwd:
            if name == pwd:
                raise ValidationError('用户密码不能相同')
            else:
                return attrs
        return attrs