Multiple Fly Applications
This guide discusses how to manage multiple Fly applications within a Rails projects. This is useful for Rails projects that need to run other services, like running a pool of Puppeteer servers that your Rails app calls to take screenshots of web pages.
Your Rails application is a Fly application, which means it has the following few things:
fly.tomlfile in the root directory
Dockerfilein the root directory that describes the image
- A “server” running on Fly’s infrastructure.
So how do you spin up multiple Fly applications for a single Rails project?
The important thing about creating multiple Fly applications within a project is keeping them organized. For our example, we’ll setup a Redis server application and keep it in the
./fly/applications folder within our project repo.
Let’s get started by running the following commands:
mkdir -p fly/applications/redis
From inside the
fly/applications/redis folder, run:
fly launch --image flyio/redis:6.2.6 --no-deploy --name my-project-name-redis
This command will create a
fly.toml file that can be further configured for your application’s needs.
Next, deploy the application:
Fly creates DNS hosts for each of your applications that are not surprising.
In the future, when it’s time to deploy updates to your Fly application within a Fly application, run: