I encounter a weird import error when I try to deploy an app built on flask, sqlalchemy on a server. The app works well when I run it on my localhost. However, it raises an import error when I run the app on a server. I suspect the cause of my problem is a circular import. But it's really weird that it works on a local environment but fails on a server environment.
I have file structure looks like the following:
.
├── __main__.py
├── instance
│ ├── config.cfg
├── theapp
│ ├── __init__.py
│ ├── models.py
│ └── views.py
init.py
# File for initializing the application and set up global variables(app, db)
...
from flask.ext.sqlalchemy import SQLAlchemy
app = Flask(__name__)
CONFIG_FILE = os.path.join(app.instance_path, 'config.cfg')
# Instantiate the application and initializes the login manager.
def create_app(app, config):
app.config.update(SECRET_KEY=config['key']['SECRET_KEY'], SQLALCHEMY_DATABASE_URI=config['app']['SQLALCHEMY_DATABASE_URI'],
DEBUG=config['app']['DEBUG'])
# Read configuration
config = ConfigParser()
config.read(CONFIG_FILE)
create_app(app, config)
db = SQLAlchemy(app)
# These imports are useful. They help to avoid cyclic import
from lemur import views, models
views.py
from theapp import (app, db)
...
models.py
from theapp import db
...
main.py
from theapp import app
if __name__ == '__main__':
app.run()
The error is(in views.py):
cannot import name models
I have tried a method suggested here but it doesn't work.
