hello.py

import os
from threading import Thread

from flask import Flask, render_template, session, redirect, url_for, flash
from flask_script import Manager, Shell
from flask_bootstrap import Bootstrap
from flask_moment import Moment
from datetime import datetime
from flask_wtf import FlaskForm
from wtforms import StringField, SubmitField
from wtforms.validators import DataRequired
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate, MigrateCommand
from flask_mail import Mail, Message


app = Flask(__name__)
app.config['SECRET_KEY'] = "ssss"
bootstrap = Bootstrap(app)
moment = Moment(app)
manager = Manager(app)
basedir = os.path.abspath(os.path.dirname(__file__))
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'data.sqlite')
app.config['SQLALCHEMY_COMMIT_ON_TEARDOWN'] = True
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
db = SQLAlchemy(app)
migrate = Migrate(app,db)
app.config['MAIL_SERVER'] = 'smtp.googlemail.com' 
app.config['MAIL_PORT'] = 587
app.config['MAIL_USE_TLS'] = True
app.config['MAIL_USERNAME'] = os.environ.get('MAIL_USERNAME')
app.config['MAIL_PASSWORD'] = os.environ.get('MAIL_PASSWORD')
mail = Mail(app)
app.config['FLASKY_MAIL_SUBJECT_PREFIX'] = '[FLasky]'
app.config['FLASKY_MAIL_SENDER'] = 'Flasky Admin <flasky@example.com>'
app.config['FLASKY_ADMIN'] = os.environ.get('FLASKY_ADMIN')

def send_mail(to, subject, template, **kwargs):
    msg = Message(subject=app.config['FLASKY_MAIL_SUBJECT_PREFIX'] + subject, sender=app.config['FLASKY_MAIL_SENDER'] , recipients=[to])
    msg.body = render_template(template + '.txt', **kwargs)
    msg.html = render_template(template + '.html', **kwargs)
    thr = Thread(target=send_async_mail, args=[msg])
    thr.start()
    return thr

def send_async_mail(msg):
    with app.app_context():
        mail.send(msg)

class Role(db.Model):
    __tablename__ = 'roles'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(64), unique=True)
    users = db.relationship('User', backref='role', lazy='dynamic')

    def __repr__(self):
        return '<Role %r>' % self.name


class User(db.Model):
    __tablename__ = 'users'
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(64), unique=True, index=True)
    role_id = db.Column(db.Integer, db.ForeignKey('roles.id'))

    def __repr__(self):
        return '<User %r>' % self.username


def make_shell_context():
    return dict(app=app, db=db, User=User, Role=Role, mail=mail)
manager.add_command("shell", Shell(make_context=make_shell_context))
manager.add_command("db", MigrateCommand)

class NameForm(FlaskForm):
    name = StringField('What is your name?', validators=[DataRequired()])
    submit = SubmitField('Submit')


@app.route('/', methods=['GET', 'POST'])
def index():
    form = NameForm()
    if form.validate_on_submit():
        user = User.query.filter_by(username=form.name.data).first()
        if user is None:
            user = User(username=form.name.data)
            db.session.add(user)
            session['known'] = False
            if app.config['FLASKY_ADMIN']:
                send_mail(app.config['FLASKY_ADMIN'], 'New User', 'mail/new_user', user=user)
        else:
            session['known'] = True
        session['name'] = form.name.data
        return redirect(url_for('index'))
    return render_template('index.jinja', form=form, name=session.get('name'), known=session.get('known', False))


@app.route('/user/<name>')
def user(name):
    return render_template('user.jinja', name=name)


@app.errorhandler(404)
def page_not_found(e):
    return render_template('404.jinja'), 400


@app.errorhandler(500)
def internal_server_error(e):
    return render_template('500.jinja'), 500


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