Mailspree is a mailing service which delegates mailsending to different mail service providers. It aims to be fault tolerant, failing over to another mail service provider if there was a problem with the one that tried to send the email.
Mailspree is written in go which is great for writing services. Mailspree is exposed as a http api, with token authentication. It currently supports mailgun and sendgrid. It has a simple circuit breaker, which prevents a mail service from being used for some time, if it has been having problems.
The http api is documented in the api reference
The easiest way to run the mailspree service is using docker. You can either grab the latest image from dockerhub blacksails/mailspree, or build the image from source using the following instructions:
git clone git@github.com:blacksails/mailspree.git
cd mailspree-ui
npm install
npm run build
docker build -t blacksails/mailspree .Instead of using docker run you can save a create an environment varibale
file in the directory, called mailspree-vars.env, which contains the
environment variable. See the
mailspree-vars.env.example file for an
example. Then run the mailspree container with docker compose.
docker-compose up
Currently the api allows that the consumer supplies the from email, which can be problematic due to SPF checks.
Say a user wants to send an eamil from test@test.com to someone, when we send the email, the mail service that we used for sending the email will be checked against the SPF record of test.com, and it might very well get bounced.
Therefore you should be sure that the mailing services you have configured with mailspree, are allowed to send mails from the domain that you want as the sender.
I was making this project with a set time, and there are certainly areas in the application that would be nice to improve. To read more about these, checkout the issues.
To see a demo of the project go to the mailspree-ui project and follow the instructions.
I am new to the go eco system. I started looking into go during my summer holidays 2016. There might and most likely are pieces of the code that could be written more go idiomatic.
Author: Benjamin Nørgaard (blacksails)