模型类序列化器ModelSerializer

定义

比如我们创建一个bookinfoserializer

class bookinfoserializer(serializers.modelserializer):
    """图书数据序列化器"""
    class meta:
        model = bookinfo
        fields = '__all__'

• model指明参照哪个模型类
• fields指明为模型类的哪些字段生成

我们可以在python manage.py shell中查看自动生成的bookinfoserializer的具体实现

>>> from booktest.serializers import bookinfoserializer
>>> serializer = bookinfoserializer()
>>> serializer
bookinfoserializer():
    id = integerfield(label='id', read_only=true)
    btitle = charfield(label='名称', max_length=20)
    bpub_date = datefield(allow_null=true, label='发布日期', required=false)
    bread = integerfield(label='阅读量', max_value=2147483647, min_value=-2147483648, required=false)
    bcomment = integerfield(label='评论量', max_value=2147483647, min_value=-2147483648, required=false)
    image = imagefield(allow_null=true, label='图片', max_length=100, required=false)

2.指定字段

1）使用字段来明确字段，__all__表名包含所有字段，也可以写明具体哪些字段，如

class bookinfoserializer(serializers.modelserializer):
    """图书数据序列化器"""
    class meta:
        model = bookinfo
        fields = ('id', 'btitle', 'bpub_date')

2）使用排除可以明确排除掉哪些字段

class bookinfoserializer(serializers.modelserializer):
    """图书数据序列化器"""
    class meta:
        model = bookinfo
        exclude = ('image',)

3）默认modelserializer使用主键作为关联字段，但是我们可以使用depth来简单的生成嵌套表示，depth应该是整数，表明嵌套的层级数量。

class heroinfoserializer2(serializers.modelserializer):
    class meta:
        model = heroinfo
        fields = '__all__'
        depth = 1

形成的序列化器如下：

heroinfoserializer():
    id = integerfield(label='id', read_only=true)
    hname = charfield(label='名称', max_length=20)
    hgender = choicefield(choices=((0, 'male'), (1, 'female')), label='性别', required=false, validators=[<django.core.valators.minvaluevalidator object>, <django.core.validators.maxvaluevalidator object>])
    hcomment = charfield(allow_null=true, label='描述信息', max_length=200, required=false)
    hbook = nestedserializer(read_only=true):
        id = integerfield(label='id', read_only=true)
        btitle = charfield(label='名称', max_length=20)
        bpub_date = datefield(allow_null=true, label='发布日期', required=false)
        bread = integerfield(label='阅读量', max_value=2147483647, min_value=-2147483648, required=false)
        bcomment = integerfield(label='评论量', max_value=2147483647, min_value=-2147483648, required=false)
        image = imagefield(allow_null=true, label='图片', max_length=100, required=false)

4）显示指明字段，如：

class heroinfoserializer(serializers.modelserializer):
    hbook = bookinfoserializer()

    class meta:
        model = heroinfo
        fields = ('id', 'hname', 'hgender', 'hcomment', 'hbook')

5）指明只读字段

可以通过read_only_fields指明只读字段，即仅用于序列化输出的字段

class bookinfoserializer(serializers.modelserializer):
    """图书数据序列化器"""
    class meta:
        model = bookinfo
        fields = ('id', 'btitle', 'bpub_date'， 'bread', 'bcomment')
        read_only_fields = ('id', 'bread', 'bcomment')

3.添加额外参数

我们可以使用extra_kwargs参数为modelserializer添加或修改原有的选项参数

class bookinfoserializer(serializers.modelserializer):
    """图书数据序列化器"""
    class meta:
        model = bookinfo
        fields = ('id', 'btitle', 'bpub_date', 'bread', 'bcomment')
        extra_kwargs = {
            'bread': {'min_value': 0, 'required': true},
            'bcomment': {'min_value': 0, 'required': true},
        }

# bookinfoserializer():
#    id = integerfield(label='id', read_only=true)
#    btitle = charfield(label='名称', max_length=20)
#    bpub_date = datefield(allow_null=true, label='发布日期', required=false)
#    bread = integerfield(label='阅读量', max_value=2147483647, min_value=0, required=true)
#    bcomment = integerfield(label='评论量', max_value=2147483647, min_value=0, required=true)