Implementing the notification service

Now that we have everything set up, and the files that we are going to use as a template to send emails to the customers of the online (video) game store are in place in the python-blueprints S3 bucket, it is time to start implementing the notification service.

Let's go ahead and create a file called app.py in the notifier directory, and to start with, let's add some imports:

import smtplib
from http import HTTPStatus
from smtplib import SMTPAuthenticationError, SMTPRecipientsRefused

from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart

import boto3
from botocore.exceptions import ClientError

from flask import Flask
from flask import request, Response

from jinja2 import Template
import json

First, we import the JSON module so we can serialize and deserialize data. We import HTTPStatus from the HTTP module so we can use the HTTP status constants when sending responses back from the service's endpoints.

Then we import the...