Note to the Student/Instructor

There several ways to setup a configuration for this project. It all depends on the goals of the class or student.

• Use smtp.gmail.com as the email server. This is probably the simplest but perhaps not the "best" way. Each student would be required to create a Gmail account and "app password".


• Set up a single SMTP server for the class. This would require extra hardware. However, you would only need a SBC (Single Board Computer) because not a lot of "horsepower" would be required. (Raspberry Pi?)


• The most complex and interesting would for every student to install and configure a SMTP server on their own computer. This would require for each student to have a computer. (Tablets and smart phones would be useless.)

Questions:

• Could Pi-hole be used as a DNS for this project?
• What about a docker container running a SMTP server?

Note: A lab with old obsolete computers running Linux would be great. I'm sure there is a lot of hardware sitting in closets somewhere collecting dust. There are places that would probably donate them just to get rid of them.

The Tale

You are working for company XYZ. You are responsible for writing and maintaining a cron job that runs at midnight. It checks the status of various processes. The last thing the program does is send you an email with the status of each process. (Sometimes detailed status information is written to a file if a problem is detected. Th email will notify the receiver of the file's creation.)

You come in every morning and read the email and see what problems were detected (if any).

If you do not receive an email, the monitoring cron jobs has a problem that you must fix.

Note: this once a day scenario is assumed to be sufficient. However, you may need to check the status more often. You may decide to send a text messages to insure a more intermediate response. (This is not part of this project.)

For this project use SMTP.

Project #1

Write a program that sends yourself an email. Read the email with your normal email client.

The message can be a text string for this project.

Project #2

Write a program that reads a text file and sends it as an email.

Project #3

Read system information and send a summary as an email:

• system log
• open ports
• disk usage
• system resource usage
• other system stats

(See the instructor for more information about this project.)

Project #4

Email attachments such as images, pdf files, etc.

Project #5

Write a program to read email messages on a server.

Project #6

Create and test a cron job that sends an email. Perhaps containing some system information (see project #3).

Gmail

Create a Gmail (Google) account
Send Email Using yagmail in Python
Delete your Google Account
Send Emails in Python with Gmail
How to Send Emails in Python with Gmail (Mailtrap)
Gmail help: Sign in with app passwords
How to Use the Gmail SMTP Server to Send Emails for Free
Gmail SMTP Settings (Updated Guide)
yagmail Documentation Release 0.10.189 (pdf)
My Notes on Creating a Google App Account

Links

Simple Mail Transfer Protocol (Wikipedia)
smtplib — SMTP protocol client
Sending mail from Python using SMTP
How to Send an Email in Python (2022)
RFC 5321: Simple Mail Transfer Protocol

Free (and not so free) SMTP Servers

The Four Horsemen of Linux Mail Transfer: Exim, Postfix, Sendmail, and Qmail
Howto install EXIM4 mail server in ubuntu and LinuxMint
3 easy steps to setting up your simple SMTP server
11 Free SMTP Server Solutions for Marketers & Developers (2023)
How To Set Up Your Own Email Server
Free SMTP Server for Testing (14 days free)
Mailtrap (100 emails per month free)
Mailtrap - email testing
Python - aiosmtpd - An asyncio based SMTP server
How to set up your own Docker mail server step by step

Cron Jobs

Setting up a cron job in Windows
How to Automate Tasks with cron Jobs in Linux

Definitions

base64	Base64 is used to encode binary data as printable text. This allows you to transport binary data over protocols that cannot handle it.
cron job	Cron jobs are used to automating tasks that run in the background periodically. Cron is a time-based task or job organizer in operating systems. These scheduled jobs or tasks are referred to as cron Jobs.
daemon	In computing, a daemon (pronounced DEE-muhn) is a program that runs continuously as a background process and wakes up to handle periodic service requests which often come from remote processes. Daemons are processes that run unattended and usually started when the system starts, and run until the system stops.
IMAP	Internet Message Access Protocol is a protocol for accessing email from a mail server or service. IMAP allows a client e-mail program to access remote message stores as if they were local.
MIME	(Multipurpose Internet Mail Extensions) is an extension of SMTP. It lets users exchange different kinds of data files, including audio, video, images, and application programs using email. Unlike SMTP, MIME supports sending both ASCII text and non-ASCII data. For text in character sets other than ASCII, the MIME protocol is required.
POP3	(Post Office Protocol) is an older protocol that was originally designed to be used on only one computer. Unlike modern protocols that use two-way synchronization, POP3 only supports one-way email synchronization, only allowing users to download emails from a server to a client.
protocol	In networking, a protocol is a standardized set of rules for formatting and processing data. Protocols enable computers to communicate with one another.
SMTP	(Simple Mail Transfer Protocol) is used to send and receive email. It primarily sends messages to a server for forwarding.