This repo is a coursework assignment. The task was to create a basic EMail delivery service, using microservices.
Finally, all those microservices had to be containerised using Docker.

This service is made of 3 microservices:

1. A Mail Submission Agent or "MSA", which acts as a client. The user interacts with this service to write emails to the
outbox, read their entire inbox, read a single email or delete an email. The MSA also writes email to the inbox when an email
is sent to the user. The MSA is linked to a single user, e.g: user1@domain.com

2. A Message Transfer Agent or "MTA", which acts as a broker. The MTA scans each outbox in its SLD name, and send them
to their corresponding MTA. Once an MTA receives an email, it dispatches it to the right MSA. An MTA is linked to a
SLD name, e.g: domain.com

3. A Bluebook which acts as a record of the IP address of each MTA. When an MTA sends one email to another, they first
query the Bluebook to find the IP address of the destination MTA.