TODO: add badges
__/\\\\\\\\\\\\__________/\\\\\_________/\\\\\\\\\____________/\\\\\\\\\_
_\/\\\////////\\\______/\\\///\\\_____/\\\///////\\\_______/\\\////////__
_\/\\\______\//\\\___/\\\/__\///\\\__\/\\\_____\/\\\_____/\\\/___________
_\/\\\_______\/\\\__/\\\______\//\\\_\/\\\\\\\\\\\/_____/\\\_____________
_\/\\\_______\/\\\_\/\\\_______\/\\\_\/\\\//////\\\____\/\\\_____________
_\/\\\_______\/\\\_\//\\\______/\\\__\/\\\____\//\\\___\//\\\____________
_\/\\\_______/\\\___\///\\\__/\\\____\/\\\_____\//\\\___\///\\\__________
_\/\\\\\\\\\\\\/______\///\\\\\/_____\/\\\______\//\\\____\////\\\\\\\\\_
_\////////////__________\/////_______\///________\///________\/////////__
A stupid deployment utility!
dorc is a tool for deploying simple backend services with a green–blue strategy.
dorc as it stands will only function on linux systems that use SystemD.
That's pretty much the only requirement.
Binaries need to have a way to set which port they listen on (e.g., ./yourbin --port 8081)
You may run into trouble if your software uses filesystem as permanent storage if that data is stored relative to the working directory.
That means you should be storing data in an external database, or a bucket, or in some absolute path like /etc/yourapp/data.
If you need more (or different) functionality, use a more mainstream deployment tool like k8s or docker swarm.
Say you're Devin W. Brite. You host your website (dwbrite.com) on a Raspberry Pi or a VPS. Your website is a self-hosted binary with a working directory, hosted on port 8081 with nginx sitting in front. You want to deploy new versions of your website without any downtime. What do you do?
You could run two versions of your site on your machine and then switch between them by enabling and disabling configurations. But that feels clunky and you technically have some downtime. And when your binaries change you'll have to stop and restart them yourself.
Setting up k8s is a pain and k8 engines are expensive. There's a few other high friction options, but you're lazy.
If that sounds like you, dorc is your solution in search of a problem!
dorc helps you set up two live versions of your application. Then it functions as a simple proxy.
Let's call a live version of an application a service, so we have a blue service and a green service.
Both services run at the same time, but only one is routed to at a time. Thus we have an active and an inactive service.
The dorc daemon will listen on a port you specify, and forward data to the port of the active version.
When you upload a new release, dorc copies the files to the inactive version and restart the binary.
Once you're ready to show the new version of your application to the world,
you can run dorc switch {my-app} and not miss a beat.
Old connections are kept alive and new connections are routed to the other service.
When you register an application with dorc, the blue and green services will be registered with SystemD.
This allows you to manage sub-services and be sure that your processes are kept alive.
I have Github Actions upload releases to my server.
Note that I upload my files to /var/tmp/dwbrite.com/.
Then I run dorc register.
I'll call my application dwbrite.com and tell dorc to listen on port 41234.
I'll also tell it that the working directory is /var/tmp/dwbrite.com,
and that the binary is at /var/tmp/dwbrite.com/target/dwbrite.com.
Then I need to set up green-dwbrite.com and blue-dwbrite.com
I leave Working dir: default, and tell dorc how to start and stop my application.
And that's it!
dorc is pretty stupid, so if I want to run more than one website, I need to run nginx in front of it.
apache/nginx blue-dwbrite.com
┌─────────────────┐ ┌─────────────────┐
│ │ │. . * │
│ dwbrite.com───►:41234 │ . . │
:80,:443◄───► │ :41235◄─────► . * . * │
│ │ │ * . * :) │
│ ohej.us───────►:8080 │ .. * .│
│ │ │ * * . │
└─────────────────┘ └─────────────────┘
dorc (dwbrite.com) green-dwbrite.com
┌─────────────────┐ ┌─────────────────┐
│ active │ │ * .. .│
│ ┌───────────►:41235 │. * │
:41234◄─────┼─────┘ │ :41236◄─────► :) * . . │
│ . inactive │ │* . . * . │
│ .............:41236 │ * . .. * │
│ │ │ . * * .│
└─────────────────┘ └─────────────────┘
When a new version of my website is uploaded, dorc will copy that to the inactive service.
Then I can call dorc switch dwbrite.com to swap which service is considered active.
If I run into any problems, or if I simply don't like this change,
I can call dorc switch dwbrite.com again to roll back to the previous version.
Happy deploying!
dorc relies on Nightly Rust and cargo deb:
rustup toolchain install nightlycargo install cargo-deb
Clone the project, cd into it, and run cargo +nightly deb --install