I have model like this:
class CreatedMixin(DeclarativeBase):
__abstract__ = True
#declared_attr
def updated_by(cls):
return Column(Integer, ForeignKey('user.user_id',
onupdate="cascade", ondelete="restrict"),
onupdate=CURRENT_USER_ID)
updated_at = Column(DateTime, nullable=False, default=dt.now(),
onupdate=dt.now())
And auth with repoze.what-quickstart. How to get CURRENT_USER_ID?
I think you could do the following
identity = request.environ.get('repoze.who.identity')
and the gettin the user id
id = identity['user'].id
Related
So I'm building an app and I'm trying to save new changes to my database but when I try to commit the changes in the flask using db.session.commit() it returns me the following error:
sqlalchemy.exc.NoReferencedTableError: Foreign key associated with column 'products.country_id' could not find table 'countries' with which to generate a foreign key to target column 'id'
In my models.py I have the following:
from app import db
from . import db
from datetime import datetime
def now():
return datetime.now()
class Countries(db.Model):
__tablename__ = 'countries'
__table_args__ = {'schema': 'products_data'}
id = db.Column(db.Integer, primary_key=True, unique=True, autoincrement=True)
name = db.Column(db.String(255))
code = db.Column(db.String(45))
def __repr__(self):
return f'Id {self.id}'
class Categories(db.Model):
__tablename__ = 'categories'
__table_args__ = {'schema': 'products_data'}
id = db.Column(db.Integer, primary_key=True, unique=True, autoincrement=True)
name = db.Column(db.String(255))
def __repr__(self):
return f'Id {self.id}'
class Brands(db.Model):
__tablename__ = 'brands'
__table_args__ = {'schema': 'products_data'}
id = db.Column(db.Integer, primary_key=True, unique=True, autoincrement=True)
name = db.Column(db.String(255))
logo = db.Column(db.String(5000))
feed = db.Column(db.String(5000))
feed_type = db.Column(db.String(45))
category_id = db.Column(db.Integer, db.ForeignKey('categories.id'))
country_id = db.Column(db.Integer, db.ForeignKey('countries.id'))
awinmid = db.Column(db.Integer)
def __repr__(self):
return f'Id {self.id}'
class Products(db.Model):
__tablename__ = 'products'
__table_args__ = {'schema': 'products_data'}
id = db.Column(db.Integer, primary_key=True, unique=True, autoincrement=True)
name = db.Column(db.String(255))
url = db.Column(db.Text)
category_id = db.Column(db.Integer, db.ForeignKey('categories.id'))
country_id = db.Column(db.Integer, db.ForeignKey('countries.id'))
price = db.Column(db.Float)
currency = db.Column(db.String(45))
discount_price = db.Column(db.Float)
shipping = db.Column(db.Float)
brand_id = db.Column(db.Integer, db.ForeignKey('brands.id'))
Am I doing anything wrong when associating a column in products with a foreign key? This is the first time I encounter this error so I'm really lost on what to do right now.
To fix I just added the schema to the db.ForeignKey and it worked
Example:
db.ForeignKey('products_data.countries.id')
PS:
Not my idea. Just wanted to post the answer in case someone visits the post later with the same problem.
Gord Thompson thanks for the help!
First of all, I don t see any table Categories. Secondly, you copy pasted your schema from the Products table into your Countries one.
PS: By default sqlalchemy gives the tables the name of the class (lower cased). So your __tablename__='products' does nothing actually.
EDIT:
The problem with your code lies in how you set the __table_args__ attribute. You assign an object to it, which by their specifications is wrong.
Take a look at the following example and modify your code accordingly
__table_args__ = ({'schema': 'products_data'})
Also for further reference, take a look at this https://docs.sqlalchemy.org/en/13/orm/extensions/declarative/table_config.html
I am inexperienced programmer. I'd like to add one-to-one relationship CurrencyDefault (that value will be assigned to the field in FlaskForm) between User and Currency:
class User(UserMixin, db.Model):
id = db.Column(db.Integer, db.Sequence('user_id_seq'), primary_key=True)
username = db.Column(db.String(64), index=True, unique=True)
email = db.Column(db.String(64), index=True, unique=True)
pswd_hash = db.Column(db.String(128))
expenses = db.relationship('Expense', backref='user')
currency = db.relationship('Currency', backref='user')
curr_default = ?
# ...
class Currency(db.Model):
id = db.Column(db.Integer, db.Sequence('expense_id_seq'), primary_key=True)
abbr = db.Column(db.String(10))
name = db.Column(db.String(64))
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
default = ?
# ...
What I want to achieve is to assign to each user.id one currency.id (one-to-one)
I'd like to ask for some advice what is the best way to make it.
After considering the problem I have some ideas like:
Association Table with uselist=False relationship,
Create a new class CurrencyDefault(id, user_id, currency_id),
Or maybe there is other, better way to achieve it?
I'm very curious of your point of view on this problem.
Implementing solution:
This is how my classes look like now:
class User(UserMixin, db.Model):
id = db.Column(db.Integer, db.Sequence('user_id_seq'), primary_key=True)
username = db.Column(db.String(64), index=True, unique=True)
email = db.Column(db.String(64), index=True, unique=True)
pswd_hash = db.Column(db.String(128))
currency_default_choice = db.Column(db.Integer, b.ForeignKey('currency.id'))
expenses = db.relationship('Expense', backref='user')
currency = db.relationship('Currency', backref='user', foreign_keys="Currency.user_id")
# currency_default = db.relationship(
# 'Currency',
# foreign_keys='User.currency_default_choice',
# backref='currency_default',
# uselist=False,
# )
# ...
class Currency(db.Model):
id = db.Column(db.Integer, db.Sequence('expense_id_seq'), primary_key=True)
abbr = db.Column(db.String(10), b.ForeignKey('currency_official_abbr.abbr'))
name = db.Column(db.String(64))
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
currency_default = db.relationship(
'User',
foreign_keys='User.currency_default_choice',
backref='currency_default',
uselist=False,
)
The first problem I find is that I can set Currency.id object created by other_user as currency_default_choice. How to restrict currency_default_choice only to the <Currency> that was created by this user?
What is the difference between setting relationship having foreign key in User class (currency_default_choice = db.Column(db.Integer, b.ForeignKey('currency.id'))) with:
class Currency(db.Model):
# ...
currency_default = db.relationship(
'User',
foreign_keys='User.currency_default_choice',
backref='currency_default',
uselist=False,
)
and setting this relationship on User side with:
class User(db.Model):
# ...
currency_default = db.relationship(
'Currency',
foreign_keys='User.currency_default_choice',
backref='currency_default',
uselist=False,
)
Ad.2. What seems to me is that there is no difference between these two ways because the backref parameter implicates bidirectional behavior so it doesn't matter if I placed db.relationship() in User or Currency class. Is it correct?
Using Python shell I added value to the User.currency_default
>>> app = create_app()
>>> app.app_context().push()
>>> admin = User.query.filter_by(username='admin').first()
<User(id= 1, username = admin, email = admin#admin.com)
>>> currency = Currency.query.filter_by(user=admin)
>>> currency
<flask_sqlalchemy.BaseQuery object at 0x03EA05D0>
>>> currency[0].id
1
>>> admin.currency_default = currency[0]
>>> db.session.commit()
>>> currency[0].currency_default
<User(id= 1, username = admin, email = admin#admin.com)
>>> admin.currency_default_choice
1
and then using Admin Panel after running flask run I wanted to remove introduced value but I got error that I don't understand. Why there is circular dependency between (Currency.currency_default),(User.currency_default) and (User.currency)? I don't understand what is happening. How to fix it?
sqlalchemy.exc.CircularDependencyError: Circular dependency detected.
(ProcessState(OneToManyDP(Currency.currency_default),
<Currency at 0x46542b0>, delete=False),
ProcessState(ManyToOneDP(User.currency_default),
<User at 0x4669b10>, delete=False),
SaveUpdateState(<Currency at 0x46542b0>),
ProcessState(OneToManyDP(User.currency), <User at 0x4669b10>, delete=False),
SaveUpdateState(<User at 0x4669b10>))
I am trying to return JSON or even a complete string of a returned one to many sqlalchemy query. I am using Marshmallow at this point to try do it but it keeps returning incomplete data
I have two models defined as :
class UserModel(db.Model):
__tablename__ = 'usermodel'
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(80), unique=True)
password = db.Column(db.String(120))
weekday = db.relationship('weekDay', cascade='all,delete-orphan', single_parent=True, backref=db.backref('usermodel', lazy='joined'))
class weekDay(db.Model):
__tablename__ = 'weekday'
id = db.Column(db.Integer, primary_key=True)
#Defining the Foreign Key on the Child Table
dayname = db.Column(db.String(15))
usermodel_id = db.Column(db.Integer, db.ForeignKey('usermodel.id'))
I have defined two schemas
class WeekdaySchema(Schema):
id = fields.Int(dump_only=True)
dayname = fields.Str()
class UserSchema(Schema):
id = fields.Int(dump_only=True)
username = fields.Str()
password = fields.Str()
weekday = fields.Nested(WeekdaySchema)
and finally I run the command (I pass the name in userName variable)
userlist = UserModel.query.filter_by(parentuser=userName).all()
full_schema = UserSchema(many=True)
result, errors = full_schema.dump(userlist)
print (result)
I print the result to see before I attempt to Jsonify it:
My weekday object is completely empty
'weekday': {}
Doesn anyone know how I can do this correctly
It's a one-to-many relationship and you must indicate it on UserSchema, like that
class UserSchema(Schema):
id = fields.Int(dump_only=True)
username = fields.Str()
password = fields.Str()
weekday = fields.Nested(WeekdaySchema, many=True)
read more on documentation
I'm trying to work with the example in the SQLAlchemy docs: Simplifying Association Objects
What I am struggling with understanding is how I can access the special_key. Ultimately I'd like to be able to do something like this:
for user in users
for keyword in user.keywords
keyword.special_key
Here is the code from the example:
class User(Base):
__tablename__ = 'user'
id = Column(Integer, primary_key=True)
name = Column(String(64))
# association proxy of "user_keywords" collection
# to "keyword" attribute
keywords = association_proxy('user_keywords', 'keyword')
def __init__(self, name):
self.name = name
class UserKeyword(Base):
__tablename__ = 'user_keyword'
user_id = Column(Integer, ForeignKey('user.id'), primary_key=True)
keyword_id = Column(Integer, ForeignKey('keyword.id'), primary_key=True)
special_key = Column(String(50))
# bidirectional attribute/collection of "user"/"user_keywords"
user = relationship(User,
backref=backref("user_keywords",
cascade="all, delete-orphan")
)
# reference to the "Keyword" object
keyword = relationship("Keyword")
def __init__(self, keyword=None, user=None, special_key=None):
self.user = user
self.keyword = keyword
self.special_key = special_key
class Keyword(Base):
__tablename__ = 'keyword'
id = Column(Integer, primary_key=True)
keyword = Column('keyword', String(64))
def __init__(self, keyword):
self.keyword = keyword
def __repr__(self):
return 'Keyword(%s)' % repr(self.keyword)
Am I on the right track in following this pattern here?
My goal is essentially many-to-many with an extra column containing a boolean value.
This should work:
for user in users:
for keyword in user.user_keywords:
print keyword.special_key
hi i have a many to many relationship between a user and a group.and i will like to add a user with many groups in my database.how do i do that if my database is as follows
user_group_table = Table('tg_user_group', metadata,
Column('user_id', Integer, ForeignKey('tg_user.user_id',
onupdate="CASCADE", ondelete="CASCADE")),
Column('group_id', Integer, ForeignKey('tg_group.group_id',
onupdate="CASCADE", ondelete="CASCADE"))
)
class Group(DeclarativeBase):
"""
Group definition for :mod:`repoze.what`.1
Only the ``group_name`` column is required by :mod:`repoze.what`.
"""
__tablename__ = 'tg_group'
#{ Columns
group_id = Column(Integer, autoincrement=True, primary_key=True)
group_name = Column(Unicode(16), unique=True, nullable=False)
display_name = Column(Unicode(255))
created = Column(DateTime, default=datetime.now)
#{ Relations
users = relation('User', secondary=user_group_table, backref='groups')
#{ Special methods
def __repr__(self):
return '<Group: name=%s>' % self.group_name
def __unicode__(self):
return self.group_name
#}
class User(DeclarativeBase):
"""
User definition.
This is the user definition used by :mod:`repoze.who`, which requires at
least the ``user_name`` column.
"""
__tablename__ = 'tg_user'
#{ Columns
user_id = Column(Integer, autoincrement=True, primary_key=True)
user_name = Column(Unicode(16), unique=True, nullable=False)
email_address = Column(Unicode(255), unique=True, nullable=False,
info={'rum': {'field':'Email'}})
display_name = Column(Unicode(255))
_password = Column('password', Unicode(80),
info={'rum': {'field':'Password'}})
created = Column(DateTime, default=datetime.now)
doing it this way however gives me an error
#expose()
def user_save(self, **kw):
user = User()
user.user_name = kw['user_name']
user.display_name = kw['display_name']
user.email_address = kw['Email']
user._password = kw['password']
user.groups.extend(kw['groups'])
DBSession.add(user)
DBSession.flush()
flash("successfully saved...")
flash(user)
redirect("/user_new")
pls help me solve this.thanks in advance
I believe the answer is in the error message that you havn't posted in the question. user.groups is a list of Group objects, while you assign a list of strings(?) got from form to it. Also I see no explicit DBSession.commit() call. Are you sure TurboGears will do it for you?