I'm trying to setup flask-admin model views with SQLAlchemy against 'user' and 'role' models. Instead of a function admin view I'm getting:

ValueError: Invalid model property name <class 'app.models.Role'>.desc

Stack trace:

Traceback (most recent call last):File "/Users/dbg/Projects/Python/Current/ziff/flaskbase/manage.py", line 18, in <module>app = create_app(os.getenv('APP_CONFIG') or 'default')File "/Users/dbg/Projects/Python/Current/ziff/flaskbase/app/__init__.py", line 49, in create_appadmin.add_view(RoleAdmin(Role, db.session))File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/view.py", line 288, in __init__menu_icon_value=menu_icon_value)File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 570, in __init__self._refresh_cache()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 640, in _refresh_cacheself._refresh_forms_cache()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 580, in _refresh_forms_cacheself._create_form_class = self.get_create_form()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 856, in get_create_formreturn self.get_form()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 848, in get_formreturn self.scaffold_form()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/view.py", line 607, in scaffold_formextra_fields=self.form_extra_fields)File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/form.py", line 427, in get_formfor name, p in properties:File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/form.py", line 422, in <genexpr>properties = ((x, find(x)) for x in only)File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/form.py", line 419, in findraise ValueError('Invalid model property name %s.%s' % (model, name))
ValueError: Invalid model property name <class 'app.models.Role'>.desc

I am using a flask application factory approach with blueprints. Here's my application factory.

My __init__.py file where I try and create the views on line 49:

from flask import Flask
from flask.ext.bootstrap import Bootstrap
from flask.ext.mail import Mail
from flask.ext.moment import Moment
from flask.ext.sqlalchemy import SQLAlchemy
from flask.ext.security import Security
from flask.ext.admin import Admin
from flask_s3 import FlaskS3
from flask.ext.cdn import CDN
from flask.ext.assets import Environment
from flask.ext.assets import PythonLoader as PythonAssetsLoader
from config import config# app setup
bootstrap = Bootstrap()
mail = Mail()
moment = Moment()
db = SQLAlchemy()
security = Security()
admin = Admin()
s3 = FlaskS3()
cdn = CDN()
assets_env = Environment()def create_app(config_name):app = Flask(__name__)app.config.from_object(config[config_name])app.name = app.config['APP_NAME']config[config_name].init_app(app)from .models import user_datastore, User, Rolefrom .auth.views import RoleAdmin, UserAdminbootstrap.init_app(app)mail.init_app(app)moment.init_app(app)db.init_app(app)security.init_app(app, user_datastore)admin.init_app(app)s3.init_app(app)cdn.init_app(app)assets_env.init_app(app)# Here's where I'm trying to create the viewsadmin.add_view(RoleAdmin(Role, db.session))admin.add_view(UserAdmin(User, db.session))from . import assetsassets_loader = PythonAssetsLoader(assets)for name, bundle in assets_loader.load_bundles().iteritems():assets_env.register(name, bundle)# attach asset bundles, routes, and custom error pages herefrom main import main as main_blueprintapp.register_blueprint(main_blueprint)import main.assets as main_assetsassets_loader = PythonAssetsLoader(main_assets)for name, bundle in assets_loader.load_bundles().iteritems():assets_env.register(name, bundle)from auth import auth as auth_blueprintapp.register_blueprint(auth_blueprint)return app

My ModelView classes:

from flask.ext.admin.contrib.sqla import ModelView__author__ = 'dbg'class RoleAdmin(ModelView):column_display_pk = Trueform_columns = ['id', 'desc']class UserAdmin(ModelView):column_display_pk = Trueform_columns = ['id', 'email', 'active', 'last_login_at', 'login_count', 'roles']

EDIT

Models.py

from app import db
from flask.ext.security import UserMixin, RoleMixin, SQLAlchemyUserDatastoreroles_users = db.Table('roles_users',db.Column('user_id', db.Integer(), db.ForeignKey('user.id')),db.Column('role_id', db.Integer(), db.ForeignKey('role.id')))class Role(db.Model, RoleMixin):id = db.Column(db.Integer(), primary_key=True)name = db.Column(db.String(80), unique=True)description = db.Column(db.String(255))class User(db.Model, UserMixin):id = db.Column(db.Integer(), primary_key=True)email = db.Column(db.String(256), unique=True)password = db.Column(db.String(36))active = db.Column(db.Boolean())confirmed_at = db.Column(db.DateTime())last_login_at = db.Column(db.DateTime())current_login_at = db.Column(db.DateTime())last_login_ip = db.Column(db.String(45))current_login_ip = db.Column(db.String(45))login_count = db.Column(db.Integer())roles = db.relationship('Role', secondary=roles_users,backref=db.backref('users', lazy='dynamic'))user_datastore = SQLAlchemyUserDatastore(db, User, Role)

UPDATE

Found a very helpful write-up here by this good soul. Still stuck. New error.

Traceback (most recent call last):File "/Users/dbg/Projects/Python/Current/ziff/flaskbase/manage.py", line 18, in <module>app = create_app(os.getenv('APP_CONFIG') or 'default')File "/Users/dbg/Projects/Python/Current/ziff/flaskbase/app/__init__.py", line 83, in create_appadmin.add_view(RoleAdmin(RoleAdmin, db.session))File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/view.py", line 288, in __init__menu_icon_value=menu_icon_value)File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 570, in __init__self._refresh_cache()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 632, in _refresh_cacheself._list_columns = self.get_list_columns()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/model/base.py", line 708, in get_list_columnscolumns = self.scaffold_list_columns()File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/view.py", line 371, in scaffold_list_columnsfor p in self._get_model_iterator():File "/usr/local/share/anaconda/envs/flaskbase27/lib/python2.7/site-packages/Flask_Admin-1.0.9-py2.7.egg/flask_admin/contrib/sqla/view.py", line 310, in _get_model_iteratorreturn model._sa_class_manager.mapper.iterate_properties
AttributeError: type object 'RoleAdmin' has no attribute '_sa_class_manager'

Here is another way using blueprints:

# app/__init__.pyfrom flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_admin import Admindb = SQLAlchemy()
admin = Admin(name='my-app', template_mode='bootstrap3')def create_app():app = Flask(__name__)db.init_app(app)admin.init_app(app)# Add the admin panelfrom app.admin import bp as admin_bpapp.register_blueprint(admin_bp)return app

# app/admin/__init__.pyfrom flask import Blueprintbp = Blueprint('admin_bp', __name__)from app.admin import routes

# app/admin/routes.pyfrom flask_admin.contrib.sqla import ModelView
from app import db, admin
from app.models import Cityadmin.add_view(ModelView(City, db.session))