Flask-Security user_registered Signal Not Received

I'm trying to use the user_registered signal in order to set up default roles for users when they register using flask-security as in the following link: Setting Default Role in Flask Security

In my searches I can see that there was a bug that was already addressed for this in flask-security: Not getting signal from flask-security, Fix - user_registered signal problem

I've tried the following to prove if the signal is received by the handler without any luck:

@user_registered.connect_via(app)
def user_registered_sighandler(sender, **extra):
    print("print-user_registered_sighandler:", extra)

This, however, never gets called even though the user gets registered and the signal should be sent.

If it helps I've set the flask-security configuration as follows:

app.config['SECURITY_REGISTERABLE'] = True
app.config['SECURITY_CONFIRMABLE'] = False
app.config['SECURITY_SEND_REGISTER_EMAIL'] = False
app.config['SECURITY_CHANGEABLE'] = True
app.config['SECURITY_SEND_PASSWORD_CHANGE_EMAIL'] = False

Signals from Flask-Login and Flask-Principal are working for me as I managed to confirm that the following code snippets successfully print when the signals are sent:

@user_logged_out.connect_via(app)
def on_user_logged_out(sender, user):
    print('USER LOG OUT: made it in',user)

@identity_changed.connect_via(app)
def identity_changed_ok(sender,identity):
    print('Identity changed:',identity)

For my setup I am using python 3.3 (anaconda) and using the following: Flask==0.10.1,flask-login==0.2.11,flask-principal==0.4.0,flask-security==1.7.4,blinker==1.3. Having looked at the signals in both flask-login and flask-security I'm not sure why the flask-security signals would not be working.

EDIT:

If I add print(user_registered.receivers) to a route in my app it will show that I have a receiver: {139923381372400: <function user_registered_sighandler at 0x7f42737145f0>}. If I put this same print statement within the registerable.py of flask-security just before the user_registered.send(app._get_current_object(),user=user, confirm_token=token) then it lists no receivers: {}

EDIT2:

Problem appears to be related to using python 3.3. I created a python 2.7 environment and the user_registered code worked as expected.

Full code to reproduce:

from flask import Flask,render_template
from playhouse.flask_utils import FlaskDB
import os
from flask.ext.security import Security, PeeweeUserDatastore
from flask.ext.security.signals import user_registered
from flask.ext.login import user_logged_out
from peewee import *
from playhouse.signals import Model
from flask.ext.security import UserMixin,RoleMixin

app = Flask(__name__)

app.config['ADMIN_PASSWORD']='secret'
app.config['APP_DIR']=os.path.dirname(os.path.realpath(__file__))
app.config['DATABASE']='sqliteext:///%s' % os.path.join(app.config['APP_DIR'], 'blog.db')
app.config['SECRET_KEY'] = 'shhh, secret!'
app.config['SECURITY_REGISTERABLE'] = True
app.config['SECURITY_CONFIRMABLE'] = False
app.config['SECURITY_SEND_REGISTER_EMAIL'] = False

flask_db = FlaskDB()
flask_db.init_app(app)
database = flask_db.database

class BaseModel(Model):
    class Meta:
        database=flask_db.database


class User(BaseModel, UserMixin):
    email=CharField()
    password=CharField()
    active = BooleanField(default=True)
    confirmed_at = DateTimeField(null=True)

    def is_active(self):
        return True

    def is_anonymous(self):
        return False

    def is_authenticated(self):
        return True


class Role(BaseModel, RoleMixin):
    name = CharField(unique=True)
    description = TextField(null=True)


class UserRoles(BaseModel):
    user = ForeignKeyField(User, related_name='roles')
    role = ForeignKeyField(Role, related_name='users')
    name = property(lambda self: self.role.name)
    description = property(lambda self: self.role.description)


user_datastore = PeeweeUserDatastore(database, User, Role, UserRoles)
security = Security(app, user_datastore)

@user_registered.connect_via(app)
def user_registered_sighandler(sender,**extra):
    print("print-user_registered_sighandler")

@user_logged_out.connect_via(app)
def on_user_logged_out(sender, user):
    print('USER LOG OUT: made it in',user)

@app.route('/')
def index():
    print(user_registered.receivers)
    return render_template('base.html')

database.create_tables([User,Role,UserRoles], safe=True)
app.run(debug=True)

base.html template:

<!doctype html>
<html>
  <head>
    <title>Blog</title>
  </head>
  <body>
          <ul>
            {% if current_user.is_authenticated() %}
              <li><a href="{{ url_for('security.logout',next='/') }}">Log out</a></li>
              <li><a href="{{ url_for('security.register') }}">Register</a></li>
        {% else %}
        <li><a href="{{ url_for('security.login',next='/') }}">Login</a></li>
        <li><a href="{{ url_for('security.register') }}">Register</a></li>
            {% endif %}
            {% block extra_header %}{% endblock %}
          </ul>
  </body>
</html>

回答1:

I was able to do this with something like:

security = Security(app, user_datastore,
         register_form=ExtendedRegisterForm)


@user_registered.connect_via(app)
def user_registered_sighandler(app, user, confirm_token):
    default_role = user_datastore.find_role("Pending")
    user_datastore.add_role_to_user(user, default_role)
    db.session.commit()

回答2:

If the import for user_registered is changed to the following:

from flask.ext.security import user_registered

then the signal will work as expected in python 3.3 and call the user_registered_sighandler function when a user is registered.

The user_registered signal is imported within the __init__.py file for flask-security so it is also available at the top level of the package.