AttributeError: 'UUID' object has no attribute 'replace' when using backend-agnostic GUID type
AttributeError: 'UUID' object has no attribute 'replace' when using backend-agnostic GUID type
我想在使用 SQLAlchemy 1.1.5 的 Postgresql 数据库中拥有一个类型为 uuid 的主键 ID，并使用 pg8000 适配器连接到数据库。我使用了 SQLAlchemy 文档中的 Backend-agnostic GUID Type recipe。
当我想插入数据库时，出现如下错误
File ".../guid.py", line ???, in process_result_value
return uuid.UUID(value)
File "/usr/lib/python2.7/uuid.py", line 131, in __init__
hex = hex.replace('urn:', '').replace('uuid:', '')
AttributeError: 'UUID' object has no attribute 'replace'
我的模型是这样的
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String
from guid import GUID
import uuid
base = declarative_base()
class Item(base):
__tablename__ = 'item'
id = Column(GUID(), default=uuid.uuid4, nullable=False, unique=True, primary_key=True)
name = Column(String)
description = Column(String)
def __repr__(self):
return "<Item(name='%s', description='%s')>" % (self.name, self.description)
我的资源或控制器如下所示
data = req.params
item = Item(name=data['name'], description=data['description'])
self.session.add(item)
self.session.commit()
pg8000 PostgreSQL 数据库适配器正在返回一个 uuid.UUID() 对象（参见它们的 type mapping documentation, and SQLAlchemy has passed that to the TypeDecorator.process_result_value() method.
文档中给出的实现需要一个 string，但是失败了：
>>> import uuid
>>> value = uuid.uuid4()
>>> uuid.UUID(value)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/mjpieters/Development/Library/buildout.python/parts/opt/lib/python2.7/uuid.py", line 133, in __init__
hex = hex.replace('urn:', '').replace('uuid:', '')
AttributeError: 'UUID' object has no attribute 'replace'
快速的解决方法是强制该值为字符串：
def process_result_value(self, value, dialect):
if value is None:
return value
else:
return uuid.UUID(str(value))
或者您可以先测试类型：
def process_result_value(self, value, dialect):
if value is None:
return value
else:
if not isinstance(value, uuid.UUID):
value = uuid.UUID(value)
return value
我已提交 pull request #403 以在文档中修复此问题（合并后）。
在整个系统中使用 UUID 时，这可能会非常令人沮丧。在某些情况下，可能很难控制 UUID 是以字符串形式出现还是以原始 UUID 形式出现。要解决此问题，像这样的解决方案可能会奏效。我附上了文档的示例，以确保其他所有内容仍然适用。
# TODO: Set this up such that the normal uuid interface is available as a pass through
import uuid
class UUID(uuid.UUID):
def __init__(self, hex=None, bytes=None, bytes_le=None, fields=None,
int=None, version=None):
if hex and (issubclass(type(hex), uuid.UUID) or isinstance(hex, uuid.UUID)):
hex = str(hex)
super(UUID, self).__init__(hex=hex, bytes=bytes, bytes_le=bytes_le, fields=fields, int=int, version=version)
print(UUID(uuid4())) # Now this works!
print(UUID('{12345678-1234-5678-1234-567812345678}'))
print(UUID('12345678123456781234567812345678'))
print(UUID('urn:uuid:12345678-1234-5678-1234-567812345678'))
print(UUID(bytes=b'\x12\x34\x56\x78' * 4)) # Python 3 requires this to be prefixed with b''. Docs appear to be mainly for Python 2
print(UUID(bytes_le=b'\x78\x56\x34\x12\x34\x12\x78\x56' +
b'\x12\x34\x56\x78\x12\x34\x56\x78'))
print(UUID(fields=(0x12345678, 0x1234, 0x5678, 0x12, 0x34, 0x567812345678)))
print(UUID(int=0x12345678123456781234567812345678))
请自行判断，这只是一个示例。
这应该可以解决问题：
id = Column(GUID(as_uuid=True), ...)
来自 https://bitbucket.org/zzzeek/sqlalchemy/issues/3323/in-099-uuid-columns-are-broken-with:
"If you want to pass a UUID() object, the as_uuid flag must be set to True."
我在不使用表单的情况下遇到了影响我的 ORM 的问题。我是 运行 psycopg2。我的解决方法是：
sudo pip install psycopg2-binary
重启apache后，psycopg2-binary version 2.7.5+的错误没有再出现
我也遇到了同样的问题，找了两天才发现错误前面的代码有错误：
出现以下错误，指的是 python 和 sqlalchemy
中的错误
offertemodule_1 | File "/opt/packages/database/models.py", line 79, in process_bind_param
offertemodule_1 | return "%.32x" % uuid.UUID(value).int
offertemodule_1 | File "/usr/local/lib/python3.7/uuid.py", line 157, in __init__
offertemodule_1 | hex = hex.replace('urn:', '').replace('uuid:', '')
offertemodule_1 | sqlalchemy.exc.StatementError: (builtins.AttributeError) 'builtin_function_or_method' object has no attribute 'replace'
offertemodule_1 | [SQL: SELECT product.id AS product_id, product.supplier_id AS product_supplier_id, product.supplier_product_url AS product_supplier_product_url, product.supplier_product_id AS product_supplier_product_id, product.title AS product_title, product.description AS product_description, product.brand AS product_brand, product.product_line AS product_product_line, product.buying_price_ex_vat AS product_buying_price_ex_vat, product.buying_vat AS product_buying_vat, product.vat_pct AS product_vat_pct, product.advise_price AS product_advise_price, product.estimated_days_leadtime AS product_estimated_days_leadtime, product.product_category AS product_product_category, product.nestedproducts AS product_nestedproducts, product.atttibutes_meta AS product_atttibutes_meta, product.statistics_meta AS product_statistics_meta, product.active AS product_active, product.created AS product_created, product.created_by AS product_created_by, product.modified AS product_modified, product.modified_by AS product_modified_by
offertemodule_1 | FROM product
offertemodule_1 | WHERE product.id = %(id_1)s]
offertemodule_1 | [parameters: [immutabledict({})]]
但事实证明，在此之前的一个进程向我的数据库函数发送了错误的对象
@ns_products.route('/<string:product_id>')
@api.response(404, 'product not found.')
class Details(Resource):
@api.marshal_with(product)
@api.doc(security='jwt')
@jwt_required
def get(self, product_id):
'''Returns a single product instance'''
return Product.get(id)`
应该是（注'product_id'）
@ns_products.route('/<string:product_id>')
@api.response(404, 'product not found.')
class Details(Resource):
@api.marshal_with(product)
@api.doc(security='jwt')
@jwt_required
def get(self, product_id):
'''Returns a single product instance'''
return Product.get(product_id)
因此存储在 product_id 中的 uuid 字符串实际上是一个本地 python 对象 'id'。因此它试图将字符串处理为 uuid 但失败了。
这里的实际问题是您有 default=uuid.uuid4，其中 postgres 需要 UUID 格式的字符串。你会想要像 default=lambda: str(uuid.uuid4())
这样的东西
我想在使用 SQLAlchemy 1.1.5 的 Postgresql 数据库中拥有一个类型为 uuid 的主键 ID，并使用 pg8000 适配器连接到数据库。我使用了 SQLAlchemy 文档中的 Backend-agnostic GUID Type recipe。
当我想插入数据库时，出现如下错误
File ".../guid.py", line ???, in process_result_value
return uuid.UUID(value)
File "/usr/lib/python2.7/uuid.py", line 131, in __init__
hex = hex.replace('urn:', '').replace('uuid:', '')
AttributeError: 'UUID' object has no attribute 'replace'
我的模型是这样的
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String
from guid import GUID
import uuid
base = declarative_base()
class Item(base):
__tablename__ = 'item'
id = Column(GUID(), default=uuid.uuid4, nullable=False, unique=True, primary_key=True)
name = Column(String)
description = Column(String)
def __repr__(self):
return "<Item(name='%s', description='%s')>" % (self.name, self.description)
我的资源或控制器如下所示
data = req.params
item = Item(name=data['name'], description=data['description'])
self.session.add(item)
self.session.commit()
pg8000 PostgreSQL 数据库适配器正在返回一个 uuid.UUID() 对象（参见它们的 type mapping documentation, and SQLAlchemy has passed that to the TypeDecorator.process_result_value() method.
文档中给出的实现需要一个 string，但是失败了：
>>> import uuid
>>> value = uuid.uuid4()
>>> uuid.UUID(value)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/mjpieters/Development/Library/buildout.python/parts/opt/lib/python2.7/uuid.py", line 133, in __init__
hex = hex.replace('urn:', '').replace('uuid:', '')
AttributeError: 'UUID' object has no attribute 'replace'
快速的解决方法是强制该值为字符串：
def process_result_value(self, value, dialect):
if value is None:
return value
else:
return uuid.UUID(str(value))
或者您可以先测试类型：
def process_result_value(self, value, dialect):
if value is None:
return value
else:
if not isinstance(value, uuid.UUID):
value = uuid.UUID(value)
return value
我已提交 pull request #403 以在文档中修复此问题（合并后）。
在整个系统中使用 UUID 时，这可能会非常令人沮丧。在某些情况下，可能很难控制 UUID 是以字符串形式出现还是以原始 UUID 形式出现。要解决此问题，像这样的解决方案可能会奏效。我附上了文档的示例，以确保其他所有内容仍然适用。
# TODO: Set this up such that the normal uuid interface is available as a pass through
import uuid
class UUID(uuid.UUID):
def __init__(self, hex=None, bytes=None, bytes_le=None, fields=None,
int=None, version=None):
if hex and (issubclass(type(hex), uuid.UUID) or isinstance(hex, uuid.UUID)):
hex = str(hex)
super(UUID, self).__init__(hex=hex, bytes=bytes, bytes_le=bytes_le, fields=fields, int=int, version=version)
print(UUID(uuid4())) # Now this works!
print(UUID('{12345678-1234-5678-1234-567812345678}'))
print(UUID('12345678123456781234567812345678'))
print(UUID('urn:uuid:12345678-1234-5678-1234-567812345678'))
print(UUID(bytes=b'\x12\x34\x56\x78' * 4)) # Python 3 requires this to be prefixed with b''. Docs appear to be mainly for Python 2
print(UUID(bytes_le=b'\x78\x56\x34\x12\x34\x12\x78\x56' +
b'\x12\x34\x56\x78\x12\x34\x56\x78'))
print(UUID(fields=(0x12345678, 0x1234, 0x5678, 0x12, 0x34, 0x567812345678)))
print(UUID(int=0x12345678123456781234567812345678))
请自行判断，这只是一个示例。
这应该可以解决问题：
id = Column(GUID(as_uuid=True), ...)
来自 https://bitbucket.org/zzzeek/sqlalchemy/issues/3323/in-099-uuid-columns-are-broken-with:
"If you want to pass a
UUID()object, theas_uuidflag must be set to True."
我在不使用表单的情况下遇到了影响我的 ORM 的问题。我是 运行 psycopg2。我的解决方法是：
sudo pip install psycopg2-binary
重启apache后，psycopg2-binary version 2.7.5+的错误没有再出现
我也遇到了同样的问题，找了两天才发现错误前面的代码有错误：
出现以下错误，指的是 python 和 sqlalchemy
中的错误offertemodule_1 | File "/opt/packages/database/models.py", line 79, in process_bind_param
offertemodule_1 | return "%.32x" % uuid.UUID(value).int
offertemodule_1 | File "/usr/local/lib/python3.7/uuid.py", line 157, in __init__
offertemodule_1 | hex = hex.replace('urn:', '').replace('uuid:', '')
offertemodule_1 | sqlalchemy.exc.StatementError: (builtins.AttributeError) 'builtin_function_or_method' object has no attribute 'replace'
offertemodule_1 | [SQL: SELECT product.id AS product_id, product.supplier_id AS product_supplier_id, product.supplier_product_url AS product_supplier_product_url, product.supplier_product_id AS product_supplier_product_id, product.title AS product_title, product.description AS product_description, product.brand AS product_brand, product.product_line AS product_product_line, product.buying_price_ex_vat AS product_buying_price_ex_vat, product.buying_vat AS product_buying_vat, product.vat_pct AS product_vat_pct, product.advise_price AS product_advise_price, product.estimated_days_leadtime AS product_estimated_days_leadtime, product.product_category AS product_product_category, product.nestedproducts AS product_nestedproducts, product.atttibutes_meta AS product_atttibutes_meta, product.statistics_meta AS product_statistics_meta, product.active AS product_active, product.created AS product_created, product.created_by AS product_created_by, product.modified AS product_modified, product.modified_by AS product_modified_by
offertemodule_1 | FROM product
offertemodule_1 | WHERE product.id = %(id_1)s]
offertemodule_1 | [parameters: [immutabledict({})]]
但事实证明，在此之前的一个进程向我的数据库函数发送了错误的对象
@ns_products.route('/<string:product_id>')
@api.response(404, 'product not found.')
class Details(Resource):
@api.marshal_with(product)
@api.doc(security='jwt')
@jwt_required
def get(self, product_id):
'''Returns a single product instance'''
return Product.get(id)`
应该是（注'product_id'）
@ns_products.route('/<string:product_id>')
@api.response(404, 'product not found.')
class Details(Resource):
@api.marshal_with(product)
@api.doc(security='jwt')
@jwt_required
def get(self, product_id):
'''Returns a single product instance'''
return Product.get(product_id)
因此存储在 product_id 中的 uuid 字符串实际上是一个本地 python 对象 'id'。因此它试图将字符串处理为 uuid 但失败了。
这里的实际问题是您有 default=uuid.uuid4，其中 postgres 需要 UUID 格式的字符串。你会想要像 default=lambda: str(uuid.uuid4())