我有代表4个表格的模型：User，Test，Area，Issue 一个用户有多个测试，每个测试有多个区域，每个区域有多个问题 我想重构代码（工作正常）以使用棉花糖序列化我的SLQ-Alchemy对象
使用棉花糖的拳头方法行之有效。 但是，我在尝试返回一项测试时遇到了问题，包括所有方面和问题。
这是详细信息：
这是我的model.py文件
db = SQLAlchemy()
ma = Marshmallow()
class User(db.Model):
__tablename__ = 'user'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(250), nullable=False)
email = db.Column(db.String(250), nullable=False)
class Test(db.Model):
__tablename__ = 'test'
id = db.Column(db.Integer, primary_key=True)
user_id = db.Column(db.Integer, ForeignKey('user.id'))
user = relationship(User, backref=backref('tests'))
class Area(db.Model):
__tablename__ = 'area'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(30), nullable=False)
test_id = db.Column(db.Integer, ForeignKey('test.id'))
test = relationship(Test,
backref=backref('areas', cascade='all, delete-orphan')
)
user_id = db.Column(db.Integer, ForeignKey('user.id'))
user = relationship(User, backref=backref('areas'))
class Issue(db.Model):
__tablename__ = 'issue'
name = db.Column(db.String(80), nullable=False)
id = db.Column(db.Integer, primary_key=True)
area_id = db.Column(db.Integer, ForeignKey('area.id'))
area = relationship(Area,
backref=backref('issues', cascade='all, delete-orphan')
)
user_id = db.Column(db.Integer, ForeignKey('user.id'))
user = relationship(User, backref=backref('issues'))
class UserSchema(ma.ModelSchema):
class Meta:
model = User
# A User has a list of tests
test = ma.Nested('TestSchema', many=True)
class TestSchema(ma.ModelSchema):
class Meta:
model = Test
# Each test belongs to one user
user = ma.Nested('UserSchema')
# Each test has a list of areas
area = ma.Nested('AreaSchema', many=True)
class AreaSchema(ma.ModelSchema):
class Meta:
model = Area
# Each Area belongs to one test
test = ma.Nested('TestSchema')
# Each Area has a list of issues
issue = ma.Nested('IssueSchema', many=True)
class IssueSchema(ma.ModelSchema):
class Meta:
model = Issue
# Each issue belongs to one area
area = ma.Nested('AreaSchema')
所以现在这是使用棉花糖完美工作的资源。 这将返回所有测试，没有其区域，没有其问题 这样就可以了：
# This works perfectly .
# It returns all tests for the user without its Areas and without Issues
# See line 26 the use of tests = tests_schema.dump(results).data
tests_schema = TestSchema(many=True)
class Tests(Resource):
""" This method return the list of tests for the user
We expect a valid JWT token from the user that was already
validated thorugh the decorator we created: token_required"""
@token_required
def get(self, *args, **kwargs):
jwt_data = kwargs['jwt_data']
if jwt_data:
# The JWT payload contains the "user"
user_name = jwt_data["user"]
logger.info("User from JWT payload data is %s" % user_name)
userId = modelUser.getUserIDFromName(user_name)
user = modelUser.getUserInfo(userId)
results = modelTest.getAllTestsForUser(userId)
logger.info(results)
tests = tests_schema.dump(results).data
logger.info(tests)
if tests:
return jsonify(tests)
else:
response = make_response(json.dumps(
'You do not have any test'), 204)
response.headers['Content-Type'] = 'application/json'
return response
这是我遇到的问题 即时通讯在：
result = test_schema.dump（testWithAreasAndIssues）.data
# This returns just one test with ALL its Areas and ALL ISSUES
# The value returned from the DB is correct.I'm just refactoring to use Marshmallow
# line 19 returns empty
class Test(Resource):
""" GET DELETE AND PUT(modifies) a Test /api/test/<int:test_id>"""
@token_required
def get(self, test_id, *args, **kwargs):
logger.info("GET for /api/test/test_id= %s" % test_id)
jwt_data = kwargs['jwt_data']
test = getTestForJWT(jwt_data, test_id)
logger.info('test.id= %s for jwt=%s is %s' % (test_id, jwt_data, test))
logger.info('test= %s' % test)
logger.info('Calling getTestWithAreasAndIssues')
testWithAreasAndIssues = modelTest.getTestWithAreasAndIssues(
test.id)
logger.info('FullTest for testid =%s is %s' % (
test.id, testWithAreasAndIssues))
result = test_schema.dump(testWithAreasAndIssues).data
logger.info(jsonify(result))
为什么我要输入一个空字典
结果= test_schema.dump（testWithAreasAndIssues）.data
？
这里是模型中的函数，可以获取所有区域和问题的测试结果。
def getTestWithAreasAndIssues(id):
""" This method will return a table containing a test
with all its areas and each areas with all its issues.
The result are unserialized object in a table with 3 columns
So we need to later serialize them and convert them
to a herarquick view using a python dictionary"""
test = (db.session.query(Test, Area, Issue)
.join(Area)
.join(Issue)
.options(
joinedload(Test.areas)
.joinedload(Area.issues)
)
.filter(Test.id == id)
.filter(Test.id == Area.test_id)
.filter(Area.id == Issue.area_id)
).all()
return test
这是此函数的输出：
[(<Test 4>, <Area 28>, <Issue 17>),
(<Test 4>, <Area 29>, <Issue 18>),
(<Test 4>, <Area 36>, <Issue 19>),
(<Test 4>, <Area 36>, <Issue 20>),
(<Test 4>, <Area 36>, <Issue 21>)]
在使用棉花糖之前，我创建了一个函数，该函数使用此SQLAlchemy表并将其转换为python对象。
答案 0 :(得分：0)
您应该使用getTestWithAreasAndIssues()要使用的其他架构。
从拥有一个与您的TestSchema模型正确对应的Test开始：
class TestSchema(ma.ModelSchema):
class Meta:
model = Test
我还建议您检查模型，您的User模型不包含与Test，Area或Issue的关系。看一下here，以正确定义与SQLAlchemy的关系。
然后，您可以为getTestWithAreasAndIssues()返回的结果创建一个模式：
class TestSchema(ma.ModelSchema):
test = ma.Nested('TestSchema')
user = ma.Nested('UserSchema')
area = ma.Nested('AreaSchema')
答案 1 :(得分：0)
通过在模型中进行一些更改，我设法创建了与我想要的东西类似的东西（我在模型中添加了backref以及从Issue到Test的关系）。所以现在是我的模式
class UserSchema(ma.ModelSchema):
class Meta:
model = User
class TestSchema(ma.ModelSchema):
class Meta:
model = Test
class AreaSchema(ma.ModelSchema):
class Meta:
model = Area
class IssueSchema(ma.ModelSchema):
class Meta:
model = Issue
class Test_DetailedSchema(ma.ModelSchema):
test = ma.Nested('self')
areas = ma.Nested('AreaSchema', many=True, exclude=('test', 'user',))
issues = ma.Nested('IssueSchema', many=True,
include=('name', 'id', 'reference_number', 'status',))
所以我现在认为
from models.model import TestSchema
from models.model import IssueSchema
from models.model import AreaSchema
from models.model import Test_DetailedSchema
# Schemas
test_detailed_schema = Test_DetailedSchema()
test_schema = TestSchema(exclude=('user',))
areas_schema = AreaSchema(many=True, exclude=('test', 'user',))
issues_schema = IssueSchema(many=True)
在路线中，我会执行以下操作：
class Test(Resource):
""" GET DELETE AND PUT(modifies) a Test /api/test/<int:test_id>"""
@token_required
def get(self, test_id, *args, **kwargs):
test_result = modelTest.getTest(test_id)
test_details, error = test_detailed_schema.dump(test_result)
pprint.pprint({'test_details': test_details})
这是我得到的输出：
{'test': {'areas': [
{'id': 10, 'issues': [7, 8], 'name': 'Name1'},
{'id': 11, 'issues': [9], 'name': 'NameX'},
{'id': 12, 'issues': [], 'name': 'Name2'},
{'id': 13,'issues': [],'name': 'Name3'},
{'id': 14, 'issues': [], 'name': 'Name4'},
{'id': 15,'issues': [],'name': 'Name5'},
{'id': 16, 'issues': [], 'name': 'Name6'},
{'id': 17, 'issues': [], 'name': 'Name7'},
{'id': 18,'issues': [10, 11],'name': 'Name8'}],
'issues': [{
'area': 10,
'id': 7,
'name': 'This is the issueX',
'open_date': None,
'reference_number': '701',
'status': 'N',
'test': 2,
'user': 1},
{'area': 10,
'id': 8,
'name': 'This is the issueY',
'open_date': None,
'reference_number': '702',
'status': 'N',
'test': 2,
'user': 1},
{'area': 11,
'id': 9,
'name': 'This is the issueZ',
'open_date': None,
'reference_number': '703',
'status': 'N',
'test': 2,
'user': 1},
{'area': 18,
'id': 10,
'name': 'This is the issueZZ',
'open_date': None,
'reference_number': '786',
'status': 'N',
'test': 2,
'user': 1},
{'area': 18,
'id': 11,
'name': 'This is the issueXXC',
'open_date': None,
'reference_number': '787',
'status': 'N',
'test': 2,
'user': 1}]}}
那我该怎么做才能扩大问题范围，并避免：
'id': 10, 'issues': [7, 8], 'name': 'Name1'}
并改为
{'test': {'areas': [
{ 'id': 10,
'name': 'Name1'
'issues':[
{'area': 10,
'id': 7,
'name': 'This is the issueX',
'open_date': None,
'reference_number': '701',
'status': 'N',
'test': 2,
'user': 1},
{'area': 10,
'id': 8,
'name': 'This is the issueY',
'open_date': None,
'reference_number': '702',
'status': 'N',
'test': 2,
'user': 1}
]
为什么问题不在内部扩展？
答案 2 :(得分：0)
我得到了想要的东西：
test_schema = TestSchema(exclude=('user',))
areas_schema = AreaSchema(many=True, exclude=('test', 'user',))
issues_schema = IssueSchema(many=True, exclude=('test', 'user',))
及更高版本：
test, error = test_schema.dump(test_result)
areas, error = areas_schema.dump(test_result.areas)
issues, error = issues_schema.dump(test_result.issues)
return jsonify({'test': test, 'areas': areas, 'issues': issues})
如果有人知道为什么
test_detailed_schema = Test_DetailedSchema()
使用
class Test_DetailedSchema(ma.ModelSchema):
test = ma.Nested('TesSchema')
areas = ma.Nested('AreaSchema', many=True, exclude=('test', 'user',))
issues = ma.Nested('IssueSchema', many=True, exclude=('test', 'user',))
不要返回相同的结果，请在此处回复