I have an User
admin ModelView with form_extra_field constituency
and I wanted to have it dynamically loaded choices (it is SelectField). Model for this view is User
which will store constituency as id
of the item.
I tried to load choices from remote API but certainly it was wrong time to load these things because of RuntimeError: Working outside of application context. It happened at migration command ...venv/bin/flask db init -d ctiweb/migrations
. I read some API_KEY from config object which needs to have application context ...
So solution would be load choices at serving or rendering time. I don't want have the solutiont in customized template rather I want it in customized admin ModelView for User
model.
Is there such a solution? Can I overload somemethod of ModelView which has application context already (so it is during serving data or rendering template)?
part of source code from models.py
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(80), unique=True, nullable=False)
password_hash = db.Column(db.String(128))
email = db.Column(db.String(255), nullable=False)
is_superuser = db.Column(db.Boolean())
constituency_id = db.Column(db.Integer())
def __str__(self):
return self.username
@property
def password(self):
raise AttributeError("not readable attribute")
@password.setter
def password(self, password):
self.password_hash = generate_password_hash(password)
def verify_password(self, password):
return check_password_hash(self.password_hash, password)
part of source code from admin.py
from flask_admin.contrib.sqla import ModelView
class UserAdminModelView(ModelView):
def serve_constituency_choices():
consituencies = (
get_constituency(constituency_id) for constituency_id in get_constituencies()
)
return ((constituency['id'], constituency['name']) for constituency in consituencies)
column_list = ['username', 'email', 'is_superuser']
form_columns = ['username', 'email', 'password', 'is_superuser', 'constituency']
form_extra_fields = {
'password': PasswordField('Password'),
'constituency': SelectField('Constituency', choices=serve_constituency_choices())
}
Actually I have finally find a simpler solution - only with class iterator on constituency choices. I think is better than the first one :-)
class ConstituencyChoices(Iterator):
def __init__(self, first_item=None):
self.first_item = first_item
self.constituencies = None
def __next__(self):
if self.first_item is not None:
res = self.first_item
self.first_item = None
return res
if self.constituencies is None:
self.constituencies = (
get_constituency(constituency_id) for constituency_id in get_constituencies()
)
constituency = self.constituencies.__next__()
res = (constituency['id'], constituency['name'])
return res
# pylint: disable=too-many-ancestors
class UserAdminModelView(ModelView):
column_list = ['username', 'email', 'is_superuser']
form_columns = ['username', 'email', 'password', 'is_superuser', 'constituency']
form_extra_fields = {
'password': PasswordField('Password'),
'constituency': SelectField(
'Constituency',
coerce=int,
choices=ConstituencyChoices(
(0, "--- {} ---".format(_('no constituency')))
)
)
}