targets/go.go

package targets

import (
	"context"
	"fmt"

	"dagger.io/dagger"
)

const (
	GoRepo = "mcr.microsoft.com/oss/go/microsoft/golang"
)

var (
	GoModCacheKey = "go-mod-cache"
)

func InstallGo(ctx context.Context, c *dagger.Container, modCache, buildCache *dagger.CacheVolume, goVersion string) (*dagger.Container, error) {
	goRef := fmt.Sprintf("%s:%s", GoRepo, goVersion)
	dir := c.From(goRef).Directory("/usr/local/go")
	pathEnv, err := c.EnvVariable(ctx, "PATH")
	if err != nil {
		return nil, fmt.Errorf("error getting PATH: %w", err)
	}
	if pathEnv == "" {
		return nil, fmt.Errorf("PATH is empty")
	}

	return c.WithDirectory("/usr/local/go", dir).
		WithEnvVariable("PATH", "/go/bin:/usr/local/go/bin:"+pathEnv).
		WithEnvVariable("GOROOT", "/usr/local/go").
		WithEnvVariable("GOPATH", "/go").
		WithMountedCache("/root/.cache/go-build", buildCache).
		WithMountedCache("/go/pkg/mod", modCache), nil
}

func (t *Target) InstallGo(ctx context.Context, goVersion string) (*Target, error) {
	c, err := InstallGo(ctx, t.c, t.client.CacheVolume(GoModCacheKey), t.client.CacheVolume(t.name+"-go-build-cache-"+string(t.platform)), goVersion)
	if err != nil {
		return nil, err
	}

	t.goVersion = goVersion
	return t.update(c), nil
}