Allow skaffold dev —-watch-image name

Signed-off-by: David Gageot <[email protected]>

Author: dgageot

cmd/skaffold/app/cmd/cmd.go

@@ -129,6 +129,7 @@ func setFlagsFromEnvVariables(commands []*cobra.Command) {
 
 func AddDevFlags(cmd *cobra.Command) {
 	cmd.Flags().BoolVar(&opts.Cleanup, "cleanup", true, "Delete deployments after dev mode is interrupted")
+	cmd.Flags().StringArrayVarP(&opts.Watch, "watch-image", "w", nil, "Choose which artifacts to watch. Artifacts with image names that contain the expression will be watched only. Default is to watch sources for all artifacts.")
 }
 
 func AddRunDeployFlags(cmd *cobra.Command) {

pkg/skaffold/config/options.go

@@ -30,6 +30,7 @@ type SkaffoldOptions struct {
 	Profiles          []string
 	CustomTag         string
 	Namespace         string
+	Watch             []string
 }
 
 // Labels returns a map of labels to be applied to all deployed

pkg/skaffold/runner/runner.go

@@ -22,6 +22,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"strings"
 	"time"
 
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/bazel"
@@ -234,6 +235,10 @@ func (r *SkaffoldRunner) Dev(ctx context.Context, out io.Writer, artifacts []*v1
 	for i := range artifacts {
 		artifact := artifacts[i]
 
+		if !r.shouldWatch(artifact) {
+			continue
+		}
+
 		if err := watcher.Register(
 			func() ([]string, error) { return dependenciesForArtifact(artifact) },
 			func() { changed.Add(artifact) },
@@ -271,6 +276,20 @@ func (r *SkaffoldRunner) Dev(ctx context.Context, out io.Writer, artifacts []*v1
 	return nil, watcher.Run(ctx, PollInterval, onChange)
 }
 
+func (r *SkaffoldRunner) shouldWatch(artifact *v1alpha2.Artifact) bool {
+	if len(r.opts.Watch) == 0 {
+		return true
+	}
+
+	for _, watchExpression := range r.opts.Watch {
+		if strings.Contains(artifact.ImageName, watchExpression) {
+			return true
+		}
+	}
+
+	return false
+}
+
 // buildAndDeploy builds a subset of the artifacts and deploys everything.
 func (r *SkaffoldRunner) buildAndDeploy(ctx context.Context, out io.Writer, artifacts []*v1alpha2.Artifact, images *kubernetes.ImageList) error {
 	firstRun := r.builds == nil

pkg/skaffold/runner/runner_test.go

@@ -358,6 +358,7 @@ func TestBuildAndDeployAllArtifacts(t *testing.T) {
 	runner := &SkaffoldRunner{
 		Builder:  builder,
 		Deployer: deployer,
+		opts:     &config.SkaffoldOptions{},
 	}
 
 	ctx := context.Background()