I want to have a custom key for the field id, for example, id_user, I've tried the following
class UserModel(db.model, UserMixin)
...
#property
def id(self):
return self.id_user
But couldn't make it work. When I try to login it sends me this message:
{
"message": "You don't have the permission to access the requested resource. It is either read-protected or not readable by the server."
}
I ended up with a nasty solution. I cloned the UserModel object, added a duplicated field for id, with the custom key I needed and told Flask-Security to use that object as the UserModel This is the function code I used:
def clone_model(model):
data = model
attr = getattr(model, "id_user")
setattr(data, "id", attr)
return data
cUserModel = clone_model(UserModel)
user_datastore = SQLAlchemyUserDatastore(db, cUserModel, Roles)
security = Security(app, user_datastore)
Hope someone find it useful
For anybody who is using Flask-Security-Too looking to change the default id column, here is my solution.
Define the User and Role Tables as usual and just define the id column depending on your preference.
class Role(db.Model, FsRoleMixin):
__tablename__ = 'role'
id = Column(String, primary_key=True)
class Users(db.Model, FsUserMixin):
__tablename__ = 'users'
id = Column(String, primary_key=True)
For me, I need to use String primary_key Column. For that to I needed to change the many-to-many relationship table (roles_users). Below is the code snippet for the same.
# Initialize the db object
db = SQLAlchemy()
# import this Class
from flask_security.models.fsqla_v2 import FsModels
# call this after creating the db object
FsModels.db = db
FsModels.user_table_name = 'users' # If you want a different table name than the default
FsModels.role_table_name = 'role'
# Create the relationship table as per your preferences
FsModels.roles_users = db.Table(
"roles_users",
Column("user_id", String, ForeignKey("users.id")),
Column("role_id", String, ForeignKey("role.id")),
)
Related
In my application, a 'set' can have a number of 'products' associated with it. Products listed against a set must have quantities defined. For this many-to-many relationship I have followed the SQLAlchemy documentation to use an association table with an additional column (quantity).
I am trying to create a form where the user can assign products and quantities against a given set. Both the sets and products already exist in the database. The data from the form are:
set.id
product.id
quantity
This works to create a new association (e.g. set 1 is 'linked' to product 3 with quantity=XYZ) but I get an integrity error when I try to update an existing record.
I can manually add a relationship/record (dummy data) or within the Flask view function as follows:
s = Set.query.get(2)
p = Product.query.get(3)
a = Set_Product_Association(set=s, product=p, quantity=23)
db.session.add(a)
db.session.commit()
Updating the record (different quantity) manually as follows works:
s.products[0].quantity = 43
db.session.add(s)
db.session.commit()
However when I use the code from the first block instead (with the aim to update the quantity field for a given, existing set and product ID), i.e.:
a = Set_Product_Association(set=s, product=p, quantity=43)
I get an integrity error
sqlalchemy.exc.IntegrityError: (sqlite3.IntegrityError) UNIQUE constraint failed: set_product_association.set_id, set_product_association.product_id [SQL: 'INSERT INTO set_product_association (set_id, product_id, quantity) VALUES (?, ?, ?)'] [parameters: (2, 3, 43)]
I assume this is to tell me that I'm trying to append a new record rather than updating the existing one.
How should I approach this? The 'manual' method works but relies on working out the correct index in the list (i.e. for the correct product.id).
Curiously, if I use form.popluate_obj(set) in my Flask view function to process the form data as described in my question here, I can update fields but not create new 'associations'. Unfortunately, I don't know what goes on behind the scenes there....
My models are defined like so:
class Set_Product_Association(db.Model):
__tablename__ = 'set_product_association'
set_id = db.Column(db.Integer, db.ForeignKey('sets.id'), primary_key=True)
product_id = db.Column(db.Integer, db.ForeignKey('products.id'), primary_key=True)
quantity = db.Column(db.Integer)
product = db.relationship("Product", back_populates="sets")
set = db.relationship("Set", back_populates="products")
class Set(db.Model):
__tablename__ = 'sets'
id = db.Column(db.Integer, primary_key=True)
products = db.relationship("Set_Product_Association",
back_populates="set")
class Product(db.Model):
__tablename__= 'products'
id = db.Column(db.Integer, primary_key=True)
part_number = db.Column(db.String(100), unique=True, nullable=False)
sets = db.relationship("Set_Product_Association",
back_populates="product")
Edit:
I've also tried reversing the operation as suggested here:
s = Set.query.get(2)
a = Set_Product_Association()
a.quantity = 43
a.product = Product.query.get(3)
a.set = s
db.session.commit()
But I still get an error:
sqlalchemy.exc.IntegrityError: (sqlite3.IntegrityError) UNIQUE constraint failed: set_product_association.set_id, set_product_association.product_id [SQL: 'INSERT INTO set_product_association (set_id, product_id, quantity) VALUES (?, ?, ?)'] [parameters: (2, 3, 43)]
You get an integrity error because you are trying to create a new object with the same primary keys.
This:
a = Set_Product_Association(set=s, product=p, quantity=43)
Does not update, but create.
If you want to update the actual row in the table, you need to update the existing one:
assoc = Set_Product_Association.query.filter_by(set=s, product=p).first()
assoc.quantity = 43
db.session.commit()
Also, from the documentation it is advised to not use a model but an actual table.
Maybe I misunderstand the purpose of Django's update_or_create Model method.
Here is my Model:
from django.db import models
import datetime
from vc.models import Cluster
class Vmt(models.Model):
added = models.DateField(default=datetime.date.today, blank=True, null=True)
creation_time = models.TextField(blank=True, null=True)
current_pm_active = models.TextField(blank=True, null=True)
current_pm_total = models.TextField(blank=True, null=True)
... more simple fields ...
cluster = models.ForeignKey(Cluster, null=True)
class Meta:
unique_together = (("cluster", "added"),)
Here is my test:
from django.test import TestCase
from .models import *
from vc.models import Cluster
from django.db import transaction
# Create your tests here.
class VmtModelTests(TestCase):
def test_insert_into_VmtModel(self):
count = Vmt.objects.count()
self.assertEqual(count, 0)
# create a Cluster
c = Cluster.objects.create(name='test-cluster')
Vmt.objects.create(
cluster=c,
creation_time='test creaetion time',
current_pm_active=5,
current_pm_total=5,
... more simple fields ...
)
count = Vmt.objects.count()
self.assertEqual(count, 1)
self.assertEqual('5', c.vmt_set.all()[0].current_pm_active)
# let's test that we cannot add that same record again
try:
with transaction.atomic():
Vmt.objects.create(
cluster=c,
creation_time='test creaetion time',
current_pm_active=5,
current_pm_total=5,
... more simple fields ...
)
self.fail(msg="Should violated integrity constraint!")
except Exception as ex:
template = "An exception of type {0} occurred. Arguments:\n{1!r}"
message = template.format(type(ex).__name__, ex.args)
self.assertEqual("An exception of type IntegrityError occurred.", message[:45])
Vmt.objects.update_or_create(
cluster=c,
creation_time='test creaetion time',
# notice we are updating current_pm_active to 6
current_pm_active=6,
current_pm_total=5,
... more simple fields ...
)
count = Vmt.objects.count()
self.assertEqual(count, 1)
On the last update_or_create call I get this error:
IntegrityError: duplicate key value violates unique constraint "vmt_vmt_cluster_id_added_c2052322_uniq"
DETAIL: Key (cluster_id, added)=(1, 2018-06-18) already exists.
Why didn't wasn't the model updated? Why did Django try to create a new record that violated the unique constraint?
The update_or_create(defaults=None, **kwargs) has basically two parts:
the **kwargs which specify the "filter" criteria to determine if such object is already present; and
the defaults which is a dictionary that contains the fields mapped to values that should be used when we create a new row (in case the filtering fails to find a row), or which values should be updated (in case we find such row).
The problem here is that you make your filters too restrictive: you add several filters, and as a result the database does not find such row. So what happens? The database then aims to create the row with these filter values (and since defaults is missing, no extra values are added). But then it turns out that we create a row, and that the combination of the cluster and added already exists. Hence the database refuses to add this row.
So this line:
Model.objects.update_or_create(field1=val1,
field2=val2,
defaults={
'field3': val3,
'field4': val4
})
Is to semantically approximately equal to:
try:
item = Model.objects.get(field1=val1, field2=val2)
except Model.DoesNotExist:
Model.objects.create(field1=val1, field2=val2, field3=val3, field4=val4)
else:
item = Model.objects.filter(
field1=val1,
field2=val2,
).update(
field3 = val3
field4 = val4
)
(but the original call is typically done in a single query).
You probably thus should write:
Vmt.objects.update_or_create(
cluster=c,
creation_time='test creaetion time',
defaults = {
'current_pm_active': 6,
'current_pm_total': 5,
}
)
(or something similar)
You should separate your field:
Fields that should be searched for
Fields that should be updated
for example:
If I have the model:
class User(models.Model):
username = models.CharField(max_length=200)
nickname = models.CharField(max_length=200)
And I want to search for username = 'Nikolas' and update this instance nickname to 'Nik'(if no User with username 'Nikolas' I need to create it) I should write this code:
User.objects.update_or_create(
username='Nikolas',
defaults={'nickname': 'Nik'},
)
see in https://docs.djangoproject.com/en/3.1/ref/models/querysets/
This is already answered well in the above.
To be more clear the update_or_create() method should have **kwargs as those parameters on which you want to check if that data already exists in DB by filtering.
select some_column from table_name where column1='' and column2='';
Filtering by **kwargs will give you objects. Now if you wish to update any data/column of those filtered objects, you should pass them in defaults param in update_or_create() method.
so lets say you found an object based on a filter now the default param values are expected to be picked and updated.
and if there's no matching object found based on the filter then it goes ahead and creates an entry with filters and the default param passed.
I have the following model:
class Locale (models.Model):
"""
Locale model
"""
locale_id = models.AutoField(primary_key=True)
locale_name = models.CharField(max_length=800)
magister = models.ForeignKey(Magister, on_delete=models.CASCADE)
def get_name(self):
return self.locale_name
In the database, there must be exactly one locale-magister pair.
To create each locale item, an administrator has to upload the locales. This is done via a bulk upload:
try:
lcl=Locale(locale_name = data_dict["locale_name"], magister = data_dict["magister "])
# lcl.full_clean()
locales_list.append(lcl)
rows+=1
if rows==INSERTNUMBER:
try:
Locale.objects.bulk_create(locales_list)
locales_uploaded+=rows
except IntegrityError as e:
print("Error: locale bulk_create "+repr(e))
locales_list=[]
rows=0
I tried using lcl.full_clean() in my bulk upload but I get a UNIQUE constraint failed: zones_locale.locale_name error and only about 1/2 of all locales upload successfully.
I also tried using:
def validate_unique(self, exclude=None):
lcl = Locale.objects.filter(locale_id=self.locale_id)
if lcl.filter(magister=self.magister).exists():
raise ValidationError("item already exists")
But the same error occurs.
I also tried using:
class Meta:
unique_together = (("locale_name", "magister"),)
This did not work either.
From what I can tell, the problem is that there exist locales with the same name that belong to different magisters.
How can I allow locales with the same name to be uploaded while also enforcing the uniqueness of any given locale-magister pair?
What i want to do is get all userimages that use a particular foriegnkey
I'm doing this by
User.objects.get(pk=1).profile.friends.all().values_list('userimages')
but then this is what i get. What I find strange is that uservideo model is very similar to userimages and yet userimages cannot be resolved.
FieldError: Cannot resolve keyword 'userimages' into field. Choices are: about_me, display_image, friends, id, nick_name, owner, owner_id, user, user_id, uservideo
models
class UserImages(models.Model):
owner = models.ForeignKey('auth.User', related_name='UserImages')
user=models.ForeignKey(Profile,related_name="profile_owner")
# highlighted = models.TextField(default=None,blank=True,null=True)
image=models.ImageField()
pub_date=models.DateTimeField(default=now)
class UserVideo(models.Model):
owner = models.ForeignKey('auth.User', related_name='UserVideo')
# highlighted = models.TextField(default=None,blank=True,null=True)
user=models.ForeignKey(Profile)
image=models.FileField()
pub_date=models.DateTimeField(default=now)
Logic is:
Select all images from Images object where user has FK:
query = UserImages.objects.filter(user=1).all()
There are multiple ways to get this,you can try this also
userObj=User.objects.get(pk=1)
userImages = UserImages.objects.filter(user=userObj)
Images=[]
for userImage in userImages:
Images.append(userImage.image)
I'm having an issue with turbogears admin controller throwing an error when I try to edit the User, ShoppingItem or ShoppingList items (code below). The error coming up is AttributeError: 'function' object has no attribute 'primary_key'. The Local Variables in frame always come back as the same:
mapper
<Mapper at 0x3719810; ShoppingList>
fields
['id']
self
<sprox.sa.provider.SAORMProvider instance at 0x03E537B0>
value
<bound method OrderedProperties.items of <sqlalchemy.util._collections.OrderedProperties object at 0x037199F0>>
entity
<class 'insertmealhere.model.shoppinglist.ShoppingList'>
field_name
'items'
I'm having trouble figuring out what is different between this and the other many-to-many relationships that are configured elsewhere in the code and are not throwing this error. I'm running Turbogears 2.2 on Python 2.7.8 currently on a windows 8.1 system. Any help is greatly appreciated.
list_item_table = Table("list_item_table", metadata,
Column('item_id', Integer, ForeignKey('shopping_item.id', onupdate="CASCADE", ondelete="CASCADE"), primary_key=True),
Column('list_id', Integer, ForeignKey('shopping_list.id', onupdate="CASCADE", ondelete='CASCADE'), primary_key=True))
class ShoppingItem(DeclarativeBase):
__tablename__ = "shopping_item"
id = Column(Integer, primary_key=True)
name = Column(String(50))
quantity = Column(String(5))
measure = Column(String(10))
# less important optional parameters that will be useful for users
brand = Column(String(50))
list_id = Column(Integer, ForeignKey('shopping_list.id'))
shopping_list = relation("ShoppingList", secondary=list_item_table, backref="items")
def get_owner_id(self):
return self.list.user_id
#classmethod
def delete_list(cls, id, user_id):
item = DBSession.query(cls).filter_by(id=id).one() # get the item from the given ID
if item.get_owner_id() == user_id: # owned by current user
DBSession.delete(item) # delete from shopping list
return True
flash(_("You do not have authorization to perform that action."))
return False
class ShoppingList(DeclarativeBase):
__tablename__ = 'shopping_list'
id = Column(Integer, primary_key=True)
date = Column(Date, index=True, nullable=False)
static = Column(Boolean, nullable=False, default=False)
# static is true if the items from the meal plan have been imported into the shopping list. Once done you can edit
# the items in the shopping list, remove items, etc. Until the shopping list is made static it is impossible to edit
# the items that are imported from the schedule as they do not exist in the shopping list! (and we do not want to
# edit them in the recipe!
user_id = Column(Integer, ForeignKey('tg_user.user_id'))
user = relation("User", backref="shopping_lists")
date_user_list = Index('date_user_list', 'date', 'user_id')
Maybe it's the list_id = Column(Integer, ForeignKey('shopping_list.id')) in the ShoppingItem model class that's confusing SQLAlchemy?