Reflecting tables with Flask-SQLAlchemy raises RuntimeError: application not registered
<p>I have an SQLite database to manage user logins, along with an existing MySQL database.  I added the MySQL database to the Flask-SQLAlchemy <code>SQLALCHEMY_BINDS</code> config.  When I try to reflect the tables, I get the following error:</p>

<pre><code>RuntimeError: application not registered on db instance and no application bound to current context
</code></pre>

<p>How do I correctly reflect the tables?</p>

<p><code>__init__.py</code>:</p>

<pre><code>from flask import Flask
from flask.ext.sqlalchemy import SQLAlchemy
from config import config

db = SQLAlchemy()

def create_app(config_name):
    app = Flask(__name__)
    app.config.from_object(config[config_name])
    config[config_name].init_app(app)

    db.init_app(app)

    from .main import main as main_blueprint
    app.register_blueprint(main_blueprint)

    return app
</code></pre>

<p><code>manage.py</code>:</p>

<pre><code>from myapp import create_app
from flask.ext.migrate import Migrate, MigrateCommand

app = create_app(os.getenv('FLASK_CONFIG') or 'default')
manager = Manager(app)
migrate = Migrate(app, db)
manager.add_command('db', MigrateCommand)

if __name__ == '__main__':
    manager.run()
</code></pre>

<p><code>models.py</code>:</p>

<pre><code>from . import db, login_manager

db.Model.metadata.reflect(db.engine)

class Calls(db.Model):
    __table__ = db.Model.metadata.tables['Calls2']
    __bind_key__ = 'calls'

    def __repr__(self):
        return self.test1
</code></pre>



<pre><code>Traceback (most recent call last):
  File "./manage.py", line 6, in &lt;module&gt;
    from app.models import User, Role, Permission
  File "/home/ilias/Desktop/client-reporting/app/models.py", line 9, in &lt;module&gt;
    db.Model.metadata.reflect(db.engine)
  File "/home/ilias/Desktop/client-reporting/local/lib/python2.7/site-packages/flask_sqlalchemy/__init__.py", line 780, in engine
    return self.get_engine(self.get_app())
  File "/home/ilias/Desktop/client-reporting/local/lib/python2.7/site-packages/flask_sqlalchemy/__init__.py", line 809, in get_app
    raise RuntimeError('application not registered on db '
RuntimeError: application not registered on db instance and no application bound to current context
</code></pre>