Reusable Python Code Modules, Part 6 - Notifications - Email

Keeping Users Informed: Implementing Reusable Email Notification Modules

Email notifications are essential for user engagement, transactional messaging, and alerting users about important events. This guide covers how to structure reusable email notification modules in Python using Flask, manage email sending efficiently, and integrate common libraries. We will explore common email libraries, compare their features, and provide practical examples and code snippets.

Common Libraries and Tools

1. Flask-Mail

Flask-Mail is a Flask extension that provides a simple interface to set up and send emails

Key Features

• Ease of Integration: Easily integrates with Flask applications

• Support for Multiple Recipients: Allows sending emails to multiple recipients.

• Attachment Support: Enables sending attachments with emails

• Configuration Flexibility: Provides multiple configuration options for different email backends

2. Flask-Mailman

Flask-Mailman is a fork of Flask-Mail that aims to provide a more modern and actively maintained alternative

Key Features

• Enhanced Attachment Support: Improved handling of email attachments

• HTML and Plain Text Emails: Supports sending both HTML and plain text versions of emails

• Improved Backend Integration: Provides better integration with various email backends

• Compatibility: Compatible with Flask-Mail but offers additional features

3. yagmail

yagmail is a user-friendly SMTP client for sending emails with Gmail

Key Features

• Simple Configuration: Easy to set up and configure with Gmail

• Inline Attachments: Allows embedding attachments directly in the email body

• OAuth2 Support: Supports OAuth2 for secure authentication with Gmail

• HTML Support: Enables sending HTML emails with inline images

https://mailtrap.io/blog/yagmail-tutorial

4. SendGrid

SendGrid is a cloud-based email service that offers a comprehensive API for sending emails

Key Features

• Scalability: Handles large volumes of emails with ease

• Detailed Analytics: Provides insights and analytics on email delivery and engagement

• Template Support: Supports reusable email templates for consistent email formatting

• SMTP and API: Offers both SMTP and RESTful API for sending emails

Comparison

• Flask-Mail: Best for simple email sending needs with easy Flask integration

• Flask-Mailman: Ideal for applications requiring enhanced attachment handling and better backend integration

• yagmail: Suitable for applications using Gmail with simple configuration and OAuth2 support

• SendGrid: Best for scalable email sending with advanced features like analytics and templates

Examples

Example 1: Flask-Mail

Setup:

$ pip install Flask-Mail

Configuration:

from flask import Flask
from flask_mail import Mail, Message

app = Flask(__name__)
app.config['MAIL_SERVER'] = 'smtp.example.com'
app.config['MAIL_PORT'] = 587
app.config['MAIL_USE_TLS'] = True
app.config['MAIL_USERNAME'] = 'your_username'
app.config['MAIL_PASSWORD'] = 'your_password'

mail = Mail(app)

Usage:

@app.route('/send-email')
def send_email():
    msg = Message('Hello', sender='your@example.com', recipients=['user@example.com'])
    msg.body = 'This is a test email sent from Flask-Mail'
    mail.send(msg)
    return 'Email sent successfully'

Example 2: Flask-Mailman

Setup:

$ pip install Flask-Mailman

Configuration:

from flask import Flask
from flask_mailman import Mail, EmailMessage

app = Flask(__name__)
app.config['MAIL_SERVER'] = 'smtp.example.com'
app.config['MAIL_PORT'] = 587
app.config['MAIL_USE_TLS'] = True
app.config['MAIL_USERNAME'] = 'your_username'
app.config['MAIL_PASSWORD'] = 'your_password'

mail = Mail(app)

Usage:

@app.route('/send-email')
def send_email():
    msg = EmailMessage(
      subject='Hello',
      to=['user@example.com'],
      body='This is a test email sent from Flask-Mailman',
    )
    mail.send(msg)
    return 'Email sent successfully'

Example 3: yagmail

Setup:

$ pip install yagmail

Configuration:

import yagmail

yag = yagmail.SMTP('your_email@gmail.com', 'your_password')

Usage:

def send_email():
    yag.send(
      to='user@example.com', 
      subject='Hello', 
      contents='This is a test email sent from yagmail'
    )
    return 'Email sent successfully'

Example 4: SendGrid

Setup:

$ pip install sendgrid

Configuration:

import os
from sendgrid import SendGridAPIClient
from sendgrid.helpers.mail import Mail

SENDGRID_API_KEY = os.getenv('SENDGRID_API_KEY')

def send_email():
    message = Mail(
        from_email='your@example.com',
        to_emails='user@example.com',
        subject='Hello',
        html_content='<strong>This is a test email sent from SendGrid</strong>'
    )
    try:
        sg = SendGridAPIClient(SENDGRID_API_KEY)
        response = sg.send(message)
        print(response.status_code)
        print(response.body)
        print(response.headers)
    except Exception as e:
        print(str(e))
    return 'Email sent successfully'