Simple python3 program to send email from a Jinja2 template and a CSV datasource

README.txt

This is a simple Python3 program, using a CSV file with headers as datasource. Column names are injected in the template rendering to be used as variable substitution.

This is not perfect. For example, the encoding fails for address headers when there are some accentuated characters (éèà for example) in the firsname or the lastname.

The template can contain UTF-8 characters, the message is Base64 encoded before beeing sent.

accounts.csv

emailing.py

#!/usr/bin/env python3

import csv
from email import message_from_string
from email.utils import formatdate, parseaddr, make_msgid
from smtplib import SMTP

from jinja2 import Environment, PackageLoader


def main():
    # Initialize Jinja2 environment and template
    env = Environment(loader=PackageLoader('emailing', '.'))
    template = env.get_template('template.eml.j2')

    # Open CSV file
    with open('accounts.csv', 'r', newline='', encoding='utf-8') as f:
        for row in csv.DictReader(f, dialect=csv.unix_dialect):r
            # Render template
            text = template.render(**row)

            # Prepare message
            message = message_from_string(text)
            # Add date and message ID
            message['Date'] = formatdate()
            message['Message-ID'] = make_msgid()
            # Set charset
            message.set_charset('utf-8')

            # Send message
            with SMTP(host='smtp.sysnove.fr', port=587) as smtp:
                smtp.starttls()
                smtp.login('alexis@sysnove.fr', 'password')

                smtp.send_message(message)


if __name__ == '__main__':
    main()

template.eml.j2

From: "Alexis Lahouze" <alexis@sysnove.fr>
To: "{{ firstname }} {{ lastname }}" <{{ address }}>
Subject: Here is a mail to {{ address }}

Hi {{ firstname }},

Greetings from Alexis.