bootstrap.py

from flask import Flask
from ddtrace import tracer, patch
patch(sqlalchemy=True,sqlite3=True,psycopg=True)
from models import Sensor, Network, db


# configure the tracer so that it reaches the Datadog Agent
# available in another container
tracer.configure(hostname='agent')

import os
DB_USERNAME = os.environ['POSTGRES_USER']
DB_PASSWORD = os.environ['POSTGRES_PASSWORD']


def create_app():
    """Create a Flask application"""
    app = Flask(__name__)
    #app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///app.db'
    app.config['SQLALCHEMY_DATABASE_URI'] = 'postgresql://' + DB_USERNAME + ':' + DB_PASSWORD + '@' + 'db/' + DB_USERNAME
    app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

    db.init_app(app)
    initialize_database(app, db)
    return app


def initialize_database(app, db):
    """Drop and restore database in a consistent state"""
    with app.app_context():
        db.drop_all()
        db.create_all()
        first_network = Network(name='First Network', site='DEL18DT')
        first_network.sensors.extend([Sensor(name='Bulkhead 5 Water Level', value=50),
                                    Sensor(name='Bulkhead 7 Water Level', value=20),
                                    Sensor(name='Bulkhead 2 Water Level', value=40)])
        second_network = Network(name='Second Network', site='DEL23DT')
        second_network.sensors.extend([Sensor(name='Rain Sensor Front Level', value=250),
                                    Sensor(name='Rain  Sensor Back Level', value=620)])
        db.session.add(first_network)
        db.session.add(second_network)
        db.session.commit()