Respect host_only option in targets (#233)

cmd/yb/build.go

@@ -193,15 +193,19 @@ func doTargetList(ctx context.Context, pkg *yb.Package, targets []*yb.BuildTarge
 }
 
 func doTarget(ctx context.Context, pkg *yb.Package, target *yb.BuildTarget, opts *doOptions) error {
-	bio, err := newBiome(ctx, newBiomeOptions{
+	biomeOpts := newBiomeOptions{
 		packageDir:      pkg.Path,
 		target:          target.Name,
 		dataDirs:        opts.dataDirs,
 		baseEnv:         opts.baseEnv,
 		dockerClient:    opts.dockerClient,
 		targetContainer: target.Container.ToNarwhal(),
 		dockerNetworkID: opts.dockerNetworkID,
-	})
+	}
+	if target.HostOnly {
+		biomeOpts = biomeOpts.disableDocker()
+	}
+	bio, err := newBiome(ctx, biomeOpts)
 	if err != nil {
 		return fmt.Errorf("target %s: %w", target.Name, err)
 	}

cmd/yb/helpers.go

@@ -43,6 +43,14 @@ type newBiomeOptions struct {
 	dockerNetworkID string
 }
 
+func (opts newBiomeOptions) disableDocker() newBiomeOptions {
+	// Operating on copy, so free to modify fields.
+	opts.dockerClient = nil
+	opts.targetContainer = nil
+	opts.dockerNetworkID = ""
+	return opts
+}
+
 func newBiome(ctx context.Context, opts newBiomeOptions) (biome.BiomeCloser, error) {
 	if opts.dockerClient == nil {
 		l := biome.Local{

cmd/yb/run.go

@@ -78,15 +78,19 @@ func (b *runCmd) run(ctx context.Context, args []string) error {
 
 	// Run command.
 	execTarget := targets[len(targets)-1]
-	bio, err := newBiome(ctx, newBiomeOptions{
+	biomeOpts := newBiomeOptions{
 		packageDir:      pkg.Path,
 		target:          execTarget.Name,
 		dataDirs:        dataDirs,
 		baseEnv:         baseEnv,
 		dockerClient:    dockerClient,
 		targetContainer: execTarget.Container.ToNarwhal(),
 		dockerNetworkID: dockerNetworkID,
-	})
+	}
+	if execTarget.HostOnly {
+		biomeOpts = biomeOpts.disableDocker()
+	}
+	bio, err := newBiome(ctx, biomeOpts)
 	if err != nil {
 		return err
 	}