mercurio

Bare Notification Service based in Golang and SSE.

Okay, so what is it actually?

This is a prototype of a Notification Service (in the vein of what you get while using YouTube/Facebook/LinkedIn and the likes) that leverages server-sent events to deliver one way communication in a quick and safe manner. Any time there is an event on the server site, it is pushed to the client near real time. It supports unicast (one-to-one) and broadcast (one-to-many) models of event notification. And there is also an API where client can fetch previous notifications and stuff.

For security, it uses JWT -- even on the SSE channel (a.k.a. EventSource). In order to pass custom HTTP headers, I've got Viktor's EventSource Polyfill in the train.

As it is a prototype, SQLite is being used for persistence. To make it even easier, GORM is in charge of migrations and object-relational mapping.

There is also an optional feature (turned off by default) of using an underlying RabbitMQ to allow for horizontal scaling. It could well being ActiveMQ, Amazon SQS, Redis Pub/Sub or whatever message-oriented middleware platform for that matter. I went with RabbitMQ because I got it running on Docker container so why not?

What is included?

Source code is in ./src folder;
There is some manual tests on ./test folder;
While we're in the subject of tests, there is little automated tests yet;
In the folder auth there is files quite utils in dev/test time: private-key (oh so super secret) and test-tokens.txt (a few valid JWT tokens);
.env files as you'd like.

Where to go from here?

Well, production would be a nice place to land on. Even though it's not ready for production yet, it is quite in its way.

I've let things fairly well arranged and malleable for a prototype, with .env files, separation of concerns and stuff, in such a way that "not much" has to be done before a beta candidate to production, I guess.

TODO

If you'd like to get your hands dirt with this little project, there is always somenthing that could be done. Send me a pull request if like. And of course, feel free to reach me out to discuss any feature or anything else.

Tasks that I have in mind now are as follow:

Write a Dockerfile;
Definitely improve logging;
Implement a nice client side app to show case a full closed loop;
Grow up and better the automated test suite (it's quite poor yet);
Clients might be interested in receive notifications of a certain sort;
Automate GitHub pipeline;
Add HTTPS (maybe -- 'cause we can just have that on load balancer).

Copyright

Leandro Silva <leandrosilva.com.br>

leandrosilva / mercurio