Bytes #1: Mail Catcher: Dummy Email Server to catch your emails!

MailCatcher is a nice little tool to help you run a dummy email server

It’s open source - https://github.com/sj26/mailcatcher

Why would one use it? There are two use cases for which I personally used it for.

One is - trying out a program in local which needs an email server as part of setup. I couldn’t setup an email server like the ones people do in production environments or use email services like AWS Simple Email Service, as I was only simply trying out the program and not doing a production deployment. So, I used mailcatcher in this case. The program I was trying out was Discourse

Another is, I had to develop a solution in our project to send email alerts when some issue occurs. To test it out, I use mailcatcher dummy email server to see if mail sending feature works

In both cases I needed SMTP email server to send emails and mailcatcher provided it.

To check the emails sent to the mailcatcher server, there’s a web UI! :D I always used the web UI. Apparently there’s also a HTTP API, but I haven’t tried it out

How to run it? It’s written in Ruby. You can use gem and install it and run it. Or you can use Docker, there’s an official Docker image for it

Docker Image in Docker Hub - https://hub.docker.com/r/sj26/mailcatcher

Source Dockerfile for the Docker Image - https://github.com/sj26/mailcatcher/blob/master/Dockerfile

I think the below is enough

$ docker run -d --name mailcatcher -p 1025:1025 -p 1080:1080 sj26/mailcatcher

It will run the Docker container in the background with SMTP port and web server port exposed, the web server serves the web UI

What’s my recommendation on the method to run? Use Docker! :) As Ruby installation, Ruby versions, gem versions, access mode of the directories etc is too much work. Unless you work with Ruby and are pretty comfortable, you can go with Docker :)