score-flyio

A Score v1b1 transformer for Fly.io. Convert your Score application files into Fly.io apps!

Score is a platform-agnostic Workload specification to improve developer productivity and experience. Score allows you to specify the workload once and deploy the same specification to many platforms.

This CLI will transform a Score specification into a Fly.io App which can be deployed.

Usage

Installation options:

1. Curl and shell: curl https://raw.githubusercontent.com/astromechza/score-flyio/main/install.sh | sh
2. Go build the latest release locally: go install github.com/astromechza/score-flyio@latest
3. Homebrew (TODO)

$ score-flyio --help
Usage: score-flyio [global options...] <subcommand> ...

Available subcommands:
  run	Convert the input Score file into a Fly.io toml file.
  
Global options:
  -debug
    	Enable debug logging

Use "score-flyio" <subcommand> --help for more information about a given subcommand.

The run command will validate and transform the Score file into a Fly.io App Configuration (fly.toml) which can then be deployed.

$ score-flyio run --help
Usage: score-flyio [global options...] run [options...] <my-score-file.yaml>

The run subcommand converts the Score spec into a Fly.io app toml and outputs it on the standard output.

Options:
  -app string
    	The target Fly.io app name otherwise the name of the Score workload will be used
  -extension value
    	An extension in the generated TOML to apply, as json separated by a =
  -extensions string
    	A YAML file containing a list of extensions to apply to the generated TOML [{"path": string, "set": any, "delete": bool}]
  -region string
    	The target Fly.io region name otherwise the region will be assigned when you deploy

FLY_APP_NAME=score-flyio-1234
$ score-flyio run --app ${FLY_APP_NAME} examples/01-hello-world.score.yaml > fly.toml
$ fly app create ${FLY_APP_NAME}
$ fly deploy

Note that it still requires volumes to be created manually if required.

Supported Score Features

• metadata
• container
  • image (NOTE: all containers must use the same image)
  • command
  • args
  • variables (NOTE: environment variables will be merged and shared between containers)
  • 🗒️️ files
    • target
    • mode (⚠️ not supported)
    • content
    • source
    • noExpand
  • 🗒️ volumes
    • source
    • target
    • path (⚠️ not supported)
    • read_only (⚠️ not supported)
  • 🗒️ resources (NOTE: uses limits and falls back to requests)
    • limits
    • requests
  • livenessProbe
  • readinessProbe
• resources
  • metadata
  • type
  • class
• 🗒️ service (NOTE: if multiple containers are set, this will link to the first container)
  • port
  • protocol
  • targetPort

NOTE: that for any Fly.io features not directly supported by Score, you can use the --extensions to add in missing configuration.

Supported Resource Types

The supported resource types are:

• environment - For accessing local environment variables. Properties can be used for accessing environment variables like ${resources.env.SOME_KEY}.

• dns - For accessing a useful hostname of the deployment. The only available property is host, a hostname. The default class will return <app>.internal, while the external class will return the external hostname.

  • NOTE: The external class depends on a shared-ipv4 address being provisioned for the app.

• volume - For specifying the Fly.io volume name via the metadata.annotations.score-flyio/volume_name annotation. It can be referenced via ${resources.vol-name}.

  resources:
    data-volume:
      type: volume
      metadata:
        annotations:
          score-flyio/volume_name: "my_data_volume"

Metadata Interpolation

Environment Variables and File contents may interpolate values from the metadata section via ${metadata.<key>}.

Resource Interpolation

Properties from declared resources can be accessed via ${resources.<name>.<property>}.

Extensions

Once the Score spec has been converted into a Machine Config payload (see https://fly.io/docs/machines/working-with-machines/#the-machine-config-object-properties and https://docs.machines.dev/swagger/index.html#/Machines/Machines_create), Fly.io specific extensions can be applied. The extensions can be specified as a separate YAML/JSON file (see --extensions) or individually on the command line through the --extention=path=value syntax.

The extensions are applied by https://github.com/tidwall/sjson, so that path specifies a location to modify.

Extension file content:

- path: services.0.ports.0.port
  set: 443
- path: services.0.ports.0.handlers
  set: ["tls", "http"]
- path: env.EXTERNAL_SCHEMA
  delete: true

Extension command line to set a value: --extension 'env={"key":"value"}'.

Extension command line to delete a value: --extension 'env.key=.