docker/swarmkit

package genericresource

import (
    "strconv"
    "strings"

    "github.com/moby/swarmkit/v2/api"
)

func discreteToString(d *api.GenericResource_DiscreteResourceSpec) string {
    return strconv.FormatInt(d.DiscreteResourceSpec.Value, 10)
}

// Kind returns the kind key as a string
func Kind(res *api.GenericResource) string {
    switch r := res.Resource.(type) {
    case *api.GenericResource_DiscreteResourceSpec:
        return r.DiscreteResourceSpec.Kind
    case *api.GenericResource_NamedResourceSpec:
        return r.NamedResourceSpec.Kind
    }

    return ""
}

// Value returns the value key as a string
func Value(res *api.GenericResource) string {
    switch res := res.Resource.(type) {
    case *api.GenericResource_DiscreteResourceSpec:
        return discreteToString(res)
    case *api.GenericResource_NamedResourceSpec:
        return res.NamedResourceSpec.Value
    }

    return ""
}

// EnvFormat returns the environment string version of the resource
func EnvFormat(res []*api.GenericResource, prefix string) []string {
    envs := make(map[string][]string)
    for _, v := range res {
        key := Kind(v)
        val := Value(v)
        envs[key] = append(envs[key], val)
    }

    env := make([]string, 0, len(res))
    for k, v := range envs {
        k = strings.ToUpper(prefix + "_" + k)
        env = append(env, k+"="+strings.Join(v, ","))
    }

    return env
}