Using with Flask A template for using MongoFrames with Flask.

Flask is a Python web framework (full disclosure - currently Flask is my go-to framework), this snippet provides a template for creating a Flask application that uses MongoFrames.

There are various ways of creating a Flask application, we're going to be using an application factory:

# app.py

import argparse

from flask import Flask
from mongoframes import *
from pymongo import MongoClient


def create_app(env):
    """
    We use an application factory to allow the app to be configured from the
    command line at start up.
    """

    # Create the app
    app = Flask(__name__)

    # Configure the application to the specified config
    app.config['ENV'] = env
    app.config.from_object('settings.{0}.Config'.format(env))

    # Set up MongoFrames
    app.mongo = MongoClient(app.config['MONGO_URI'])
    Frame._client = app.mongo
    if app.config.get('MONGO_PASSWORD'):
        Frame.get_db().authenticate(
            app.config.get('MONGO_USERNAME'),
            app.config.get('MONGO_PASSWORD')
            )

    # ...other application set up tasks...

    return app


if __name__ == "__main__":

    # Parse the command-line arguments
    parser = argparse.ArgumentParser(description='Application server')
    parser.add_argument(
        '-e',
        '--env',
        choices=['dev', 'local', 'prod'],
        default='local',
        dest='env',
        required=False
        )
    args = parser.parse_args()

    # Create and run the application
    app = create_app(args.env)
    app.run(port=app.config.get('PORT'))

The application code here can be configured to different environments (in this case local, development or production), to start the application in the production environment we'd enter the following at the command line:

$ python app.py --prod

Each environment requires its own settings file which is used to configure the application (including potentially different database credentials), at the same level as the app.py file we create a settings folder and add Python files for each environment (e.g local.py, dev.py, prod.py). Each settings file must define a Config class the attributes of which are used as settings:

# settings/prod.py

class Config:

    # Database
    MONGO_URI = 'mongodb://localhost:27017/mydb'
    MONGO_USERNAME = 'mydb'
    MONGO_PASSWORD = 'password'

    # Debugging
    DEBUG = False

    # Networking
    PORT = 5000
    PREFERRED_URL_SCHEME = 'https'
    SERVER_NAME = 'mywebsite.com'

In my own set up I also create a DefaultConfig class which the other environment Config classes inherit from.

And that's it, you can now use MongoFrames with your Flask application :)