我有一个 flask_sqlalchemy 模型,我想使用 SQLAlchemyAutoSchema 序列化它的实例和它的实例列表:
class TestModel(Model):
id = Column(Integer, primary_key=True)
test_comments = relationship("TestCommentModel", backref=backref("test", lazy="joined"),
lazy="dynamic", foreign_keys="TestCommentModel.test_id")
def find_by_id( ... #
def find_all(... #
class TestSchema(ma.SQLAlchemyAutoSchema):
test_comments = ma.Nested(TestCommentSchema, many=True)
class Meta:
model = TestModel
dump_only = ("id",)
load_instance = True
include_fk = False
为此,我创建了上述类的两个实例,如下所示:
test_schema = TestSchema()
test_list_schema = TestSchema(many=True)
test = TestModel.find_by_id(test_id)
serialized_test = test_schema.dump(test)
tests = TestModel.find_all()
serialized_tests = {"tests": test_list_schema.dump(tests)}
那么什么是serialized_test?这是我想要的,它看起来像这样:
{"id":1, "comments": ["id": 1, "id":2]}
什么是serialized_tests?它看起来像这样:
{"tests": [
{"id":1, "comments": ["id": 1, "id":2]},
{"id":2, "comments": ["id": 3, "id":4]},
]
}
但我不需要评论。我只需要:
{"tests": [
{"id":1},
{"id":2},
]
}
我怎样才能拥有这个而不必重新定义另一个 TestSchema,例如 TestListSchema?
如果我能做这样的事情,那将非常有帮助:
test_schema = TestSchema()
test_list_schema = TestSchema(many=True)}
test_list_schema = test_list_schema.pop(test_comment) # Pseudo Code
我实际上想要做的是从实例中删除类属性。
如何做到这一点的任何解决方案?
或者如果我可以有条件地向类添加属性
# Pseudo code
class TestSchema(ma.SQLAlchemyAutoSchema):
if not many:
test_comments = ma.Nested(TestCommentSchema, many=True)
class Meta:
model = TestModel
dump_only = ("id",)
load_instance = True
include_fk = False
任何解决方案?