Flask operates mongo in two ways -- ORM

# manage.py 
# coding=utf-8 
# Flask-Script is an extension that can write scripts outside the flask application 
# Common functions: 
# Run a development server 
# Operate the database in python shell 
# Command line tasks 
# from flask_script import Manager 
#Execute the statement python manage.py save

from flask_script import Manager
from app import app, db
from models import User

manager = Manager(app)

@manager.command
def save():
    user = User("dadao3", "[email protected]")
    user.save()


@manager.command
def query_users():
    users = User.objects.all()
    for u in users:
        print u


if __name__ == "__main__":
    manager.run()


#models.py
#coding=-utf-8

from app import db

class User(db.Document):
    name = db.StringField()
    email = db.StringField()
    
    def __str__(self):
        return "name: %s--email: %s" % (self.name, self.email)

# app.py 
# coding = utf-8 
# pip install flask-mongoengine 
from flask import Flask
 from flask.ext.mongoengine import MongoEngine

app = Flask(__name__)
app.config["MONGODB_SETTINGS"] = {"db":"users"}

db = MongoEngine (app)


@app.route("/")
def main():
    return "hello world"

if __name__ == "__main__":
    app.run(debug=True)