score-implementation-sample

This score-implementation-sample is a template repo for creating a new Score implementation following the conventions laid out in Score Compose and Score K8s.

This sample comes complete with:

1. CLI skeleton including init andgenerate subcommands
   • generate --overrides-file and generate --override-property for applying Score overrides before conversion
   • generate --image for overriding the workload image before conversion.
   • Full placeholder support for ${metadata...} and ${resource...} expressions in the workload variables, files, and resource params.
2. State directory storage in .score-implementation-sample/
3. TODO in place of resource provisioning and workload conversion

To adapt this for your target platform, you should:

1. Fork the repo or use the "use as template" button in Github (this flattens the commit history)
2. Rename the go module by replacing all instances of github.com/score-spec/score-implementation-sample with your own module name.
3. Replace all other instances of score-implementation-sample with your own score-xyz name including renaming the cmd/score-implementation-sample directory.
4. Run the tests with go test -v ./....
5. Change the TODO in provisioning.go to provision resources and set the resource outputs. The existing implementation resolves placeholders in the resource params but does not set any resource outputs.
6. Change the TODO in convert.go to convert workloads into the target manifest form. The existing implementation resolves placeholders in the variables and files sections but just returns the workload spec as yaml content in the manifests.

Good luck, and have fun!

Demo

Write the following to score.yaml:

apiVersion: score.dev/v1b1
metadata:
    name: example
containers:
    main:
        image: stefanprodan/podinfo
        variables:
            key: value
            dynamic: ${metadata.name}
        files:
        - target: /somefile
          content: |
            ${metadata.name}
resources:
    thing:
        type: something
        params:
          x: ${metadata.name}

And run:

go run ./cmd/score-xyz init
go run ./cmd/score-xyz generate score.yaml

The output manifests.yaml contains the following which indicates:

1. Resources were "provisioned" and their parameters interpolated.
2. Workloads were converted by copying them to the output manifests with variables or files interpolated as required.

apiVersion: score.dev/v1b1
metadata:
    name: example
containers:
    main:
        files:
            - content: |
                example
              noExpand: true
              target: /somefile
        image: stefanprodan/podinfo
        variables:
            dynamic: example
            key: value
resources:
    thing:
        params:
            x: example
        type: something

A note on licensing

Most code files here retain the Apache licence header since they were copied or adapted from the reference score-compose which is Apache licensed. Any modifications to these files should retain the Apache licence and attribution.