pymailgen

Starting from the content of a CSV file and a template text file, pymailgen generates a list of emails to be sent out using a command-line SMTP client.

pymailgen does not send the emails itself, but it relies on external command-line tools to do it. pymailgen generates a shell script called sendall.sh that contains the list of commands to send out the emails using a command line STMP client.

This two-stage procedure has at least two advantages:

1. you can inspect the emails before sending them out;
2. in case of any issue in the sending, you have a log of what happened, and you can send the failed emails by just manually editing the sendall.sh script to keep the necessary corresponding commands.

At the moment, the only supported SMTP client is ssmtp. Some useful info to configure ssmtp for being used with Gmail are reported in this blog.

The logic of pymailgen is super simple. Therefore, it is easy to hack and customize in case a more complex logic is required to fill the template.

Install

pymailgen is available using pip:

pip install pymailgen

How it works

The elements required to generate the emails are:

• the body of the email: a plain text file template with placeholders;
• the header of the email: a plain text file with standard email header format;
• the list of recipients: a CSV file with as many optional fields as needed.

The body and the header of the email can contain placeholders in the form of {Field}. For each email, pymailgen replaces the placeholder with the value in the column Field in a CSV file containing the necessary information. Association between field and placeholder is case-sensitive.

Each individual generated email is stored in a file named email_X.txt, where X is an incremental number.

Once all the necessary data are in place, run the following command to generate the emails:

pymailgen body.txt contacts.csv --ssmtp header.txt

If the SMTP client is properly configured, the emails will be sent out by running

bash sendall.sh

In the repository, you can find an example of body, header and CSV file in the tests directory.

Blacklisting

If the input CSV file contains a column named Blacklist (case-sensitive), every row with any non-empty content in that column will be skipped during the generation of the set of emails.