pruning implemented for normal builders. need to figure out plugins

cmd/skaffold/app/cmd/cmd.go

@@ -49,6 +49,8 @@ var rootCmd = &cobra.Command{
 
 func NewSkaffoldCommand(out, err io.Writer) *cobra.Command {
 	rootCmd.PersistentPreRunE = func(cmd *cobra.Command, args []string) error {
+		// only prune if flag is set, AND we're not caching
+		opts.Prune = !(opts.NoPrune || opts.CacheArtifacts)
 		if err := SetUpLogs(err, v); err != nil {
 			return err
 		}

cmd/skaffold/app/cmd/dev.go

@@ -62,17 +62,17 @@ func dev(out io.Writer, ui bool) error {
 		catchCtrlC(cancel)
 	}
 
-	prune := func() {}
-	if !opts.NoPrune {
+	cleanup := func() {}
+	if opts.Cleanup {
 		defer func() {
-			prune()
+			cleanup()
 		}()
 	}
 
-	cleanup := func() {}
-	if opts.Cleanup {
+	prune := func() {}
+	if opts.Prune {
 		defer func() {
-			cleanup()
+			prune()
 		}()
 	}
 

pkg/skaffold/build/bazel/bazel.go

@@ -102,7 +102,7 @@ func (b *Builder) local(ctx context.Context, out io.Writer, tags tag.ImageTags,
 	if err != nil {
 		return nil, errors.Wrap(err, "getting current cluster context")
 	}
-	builder, err := local.NewBuilder(l, kubeContext, b.opts.SkipTests)
+	builder, err := local.NewBuilder(l, kubeContext, b.opts.Prune, b.opts.SkipTests)
 	if err != nil {
 		return nil, errors.Wrap(err, "getting local builder")
 	}
@@ -114,6 +114,11 @@ func (b *Builder) local(ctx context.Context, out io.Writer, tags tag.ImageTags,
 	return builder.Build(ctx, out, tags, artifacts)
 }
 
+func (b *Builder) Prune(ctx context.Context, out io.Writer) error {
+	// TODO(nkubala): implement
+	return nil
+}
+
 func setArtifact(artifact *latest.Artifact) error {
 	if artifact.ArtifactType.BazelArtifact != nil {
 		return nil

pkg/skaffold/build/cache.go

@@ -37,10 +37,12 @@ import (
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/docker"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/latest"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/util"
+	"github.com/docker/docker/api/types"
 	"github.com/google/go-containerregistry/pkg/name"
 	homedir "github.com/mitchellh/go-homedir"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
+
 	yaml "gopkg.in/yaml.v2"
 )
 
@@ -61,6 +63,7 @@ type Cache struct {
 	cacheFile     string
 	useCache      bool
 	needsPush     bool
+	prune         bool
 }
 
 var (
@@ -86,7 +89,7 @@ func NewCache(builder Builder, opts *skafconfig.SkaffoldOptions, needsPush bool)
 		logrus.Warnf("Error retrieving artifact cache, not using skaffold cache: %v", err)
 		return noCache
 	}
-	client, err := docker.NewAPIClient(!opts.NoPrune)
+	client, err := docker.NewAPIClient(opts.Prune)
 	if err != nil {
 		logrus.Warnf("Error retrieving local daemon client, not using skaffold cache: %v", err)
 		return noCache
@@ -98,6 +101,7 @@ func NewCache(builder Builder, opts *skafconfig.SkaffoldOptions, needsPush bool)
 		client:        client,
 		builder:       builder,
 		needsPush:     needsPush,
+		prune:         opts.Prune,
 	}
 }
 
@@ -139,7 +143,7 @@ func (c *Cache) RetrieveCachedArtifacts(ctx context.Context, out io.Writer, arti
 		artifact, err := c.resolveCachedArtifact(ctx, out, a)
 		if err != nil {
 			logrus.Debugf("error retrieving cached artifact for %s: %v\n", a.ImageName, err)
-			color.Red.Fprintf(out, "Unable to retrieve %s from cache; this image will be rebuilt.", a.ImageName)
+			color.Red.Fprintln(out, "Unable to retrieve %s from cache; this image will be rebuilt.", a.ImageName)
 			needToBuild = append(needToBuild, a)
 			continue
 		}
@@ -297,6 +301,12 @@ func (c *Cache) CacheArtifacts(ctx context.Context, artifacts []*latest.Artifact
 			logrus.Debugf("both image id and digest are empty for %s, skipping caching", tags[a.ImageName])
 			continue
 		}
+		entry, ok := c.artifactCache[hash]
+		if ok && c.prune {
+			if err := c.Prune(ctx, entry.ID); err != nil {
+				logrus.Warnf("error pruning evicted cache entry %s: %s", entry.ID, err.Error())
+			}
+		}
 		c.artifactCache[hash] = ImageDetails{
 			Digest: digest,
 			ID:     id,
@@ -352,6 +362,25 @@ func (c *Cache) save() error {
 	return ioutil.WriteFile(c.cacheFile, data, 0755)
 }
 
+func (c *Cache) Prune(ctx context.Context, imageID string) error {
+	resp, err := c.client.ImageRemove(ctx, imageID, types.ImageRemoveOptions{
+		Force:         true,
+		PruneChildren: true,
+	})
+	if err != nil {
+		return errors.Wrap(err, "pruning images")
+	}
+	for _, r := range resp {
+		if r.Deleted != "" {
+			logrus.Infof("deleted image %s\n", r.Deleted)
+		}
+		if r.Untagged != "" {
+			logrus.Infof("untagged image %s\n", r.Untagged)
+		}
+	}
+	return nil
+}
+
 func getHashForArtifact(ctx context.Context, builder Builder, a *latest.Artifact) (string, error) {
 	deps, err := builder.DependenciesForArtifact(ctx, a)
 	if err != nil {

pkg/skaffold/build/docker/docker.go

@@ -41,6 +41,8 @@ import (
 type Builder struct {
 	opts *config.SkaffoldOptions
 	env  *latest.ExecutionEnvironment
+
+	builder build.Builder
 }
 
 // NewBuilder creates a new Builder that builds artifacts with Docker.
@@ -102,7 +104,8 @@ func (b *Builder) local(ctx context.Context, out io.Writer, tags tag.ImageTags,
 	if err != nil {
 		return nil, errors.Wrap(err, "getting current cluster context")
 	}
-	builder, err := local.NewBuilder(l, kubeContext, b.opts.SkipTests)
+	builder, err := local.NewBuilder(l, kubeContext, b.opts.Prune, b.opts.SkipTests)
+	b.builder = builder
 	if err != nil {
 		return nil, errors.Wrap(err, "getting local builder")
 	}
@@ -111,7 +114,7 @@ func (b *Builder) local(ctx context.Context, out io.Writer, tags tag.ImageTags,
 			return nil, err
 		}
 	}
-	return builder.Build(ctx, out, tags, artifacts)
+	return b.builder.Build(ctx, out, tags, artifacts)
 }
 
 // googleCloudBuild sets any necessary defaults and then builds artifacts with docker in GCB
@@ -126,7 +129,12 @@ func (b *Builder) googleCloudBuild(ctx context.Context, out io.Writer, tags tag.
 			return nil, err
 		}
 	}
-	return gcb.NewBuilder(g, b.opts.SkipTests).Build(ctx, out, tags, artifacts)
+	b.builder = gcb.NewBuilder(g, b.opts.SkipTests)
+	return b.builder.Build(ctx, out, tags, artifacts)
+}
+
+func (b *Builder) Prune(ctx context.Context, out io.Writer) error {
+	return b.builder.Prune(ctx, out)
 }
 
 func setArtifact(artifact *latest.Artifact) error {

pkg/skaffold/build/local/local.go

@@ -53,12 +53,12 @@ func (b *Builder) buildArtifact(ctx context.Context, out io.Writer, artifact *la
 	}
 
 	if b.pushImages {
-		digest := digestOrImageID
-		imageID, err := b.getImageIDForDigest(ctx, digest)
+		imageID, err := b.getImageIDForTag(ctx, tag)
 		if err != nil {
 			logrus.Warnf("unable to inspect image: built images may not be cleaned up correctly by skaffold")
 		}
 		b.builtImages = append(b.builtImages, imageID)
+		digest := digestOrImageID
 		return tag + "@" + digest, nil
 	}
 
@@ -132,8 +132,8 @@ func (b *Builder) DependenciesForArtifact(ctx context.Context, a *latest.Artifac
 	return util.AbsolutePaths(a.Workspace, paths), nil
 }
 
-func (b *Builder) getImageIDForDigest(ctx context.Context, digest string) (string, error) {
-	insp, _, err := b.api.ImageInspectWithRaw(ctx, digest)
+func (b *Builder) getImageIDForTag(ctx context.Context, tag string) (string, error) {
+	insp, _, err := b.localDocker.ImageInspectWithRaw(ctx, tag)
 	if err != nil {
 		return "", errors.Wrap(err, "inspecting image")
 	}

pkg/skaffold/build/local/types.go

@@ -44,8 +44,8 @@ type Builder struct {
 }
 
 // NewBuilder returns an new instance of a local Builder.
-func NewBuilder(cfg *latest.LocalBuild, kubeContext string, noPrune bool, skipTests bool) (*Builder, error) {
-	api, err := docker.NewAPIClient(!noPrune)
+func NewBuilder(cfg *latest.LocalBuild, kubeContext string, prune bool, skipTests bool) (*Builder, error) {
+	localDocker, err := docker.NewAPIClient(prune)
 	if err != nil {
 		return nil, errors.Wrap(err, "getting docker client")
 	}
@@ -70,7 +70,7 @@ func NewBuilder(cfg *latest.LocalBuild, kubeContext string, noPrune bool, skipTe
 		localCluster: localCluster,
 		pushImages:   pushImages,
 		skipTests:    skipTests,
-		prune:        !noPrune,
+		prune:        prune,
 	}, nil
 }
 
@@ -91,7 +91,7 @@ func (b *Builder) Labels() map[string]string {
 // Prune uses the docker API client to remove all images built with Skaffold
 func (b *Builder) Prune(ctx context.Context, out io.Writer) error {
 	for _, id := range b.builtImages {
-		resp, err := b.api.ImageRemove(ctx, id, types.ImageRemoveOptions{
+		resp, err := b.localDocker.ImageRemove(ctx, id, types.ImageRemoveOptions{
 			Force:         true,
 			PruneChildren: true,
 		})

pkg/skaffold/build/plugin/plugin.go

@@ -148,6 +148,15 @@ func (b *Builder) DependenciesForArtifact(ctx context.Context, artifact *latest.
 	return nil, errors.New("couldn't find plugin builder to get dependencies for artifact")
 }
 
+func (b *Builder) Prune(ctx context.Context, out io.Writer) error {
+	for name, builder := range b.Builders {
+		if err := builder.Prune(ctx, out); err != nil {
+			return errors.Wrapf(err, "pruning images for builder %s", name)
+		}
+	}
+	return nil
+}
+
 func retrieveArtifactsByPlugin(artifacts []*latest.Artifact) map[string][]*latest.Artifact {
 	m := map[string][]*latest.Artifact{}
 	for _, a := range artifacts {

pkg/skaffold/config/options.go

@@ -41,6 +41,7 @@ type SkaffoldOptions struct {
 	ExperimentalGUI   bool
 	EnableRPC         bool
 	NoPrune           bool
+	Prune             bool // this is a logical combination of NoPrune and CacheArtifacts
 	Profiles          []string
 	CustomTag         string
 	Namespace         string

pkg/skaffold/docker/image.go

@@ -49,6 +49,8 @@ type LocalDaemon interface {
 	Load(ctx context.Context, out io.Writer, input io.Reader, ref string) (string, error)
 	Tag(ctx context.Context, image, ref string) error
 	ImageID(ctx context.Context, ref string) (string, error)
+	ImageInspectWithRaw(ctx context.Context, image string) (types.ImageInspect, []byte, error)
+	ImageRemove(ctx context.Context, image string, opts types.ImageRemoveOptions) ([]types.ImageDeleteResponseItem, error)
 	RepoDigest(ctx context.Context, ref string) (string, error)
 	FindTaggedImageByDigest(ctx context.Context, id string) (string, error)
 	FindImageByID(ctx context.Context, id string) (string, error)
@@ -345,6 +347,14 @@ func (l *localDaemon) FindTaggedImageByDigest(ctx context.Context, digest string
 	return "", nil
 }
 
+func (l *localDaemon) ImageInspectWithRaw(ctx context.Context, image string) (types.ImageInspect, []byte, error) {
+	return l.apiClient.ImageInspectWithRaw(ctx, image)
+}
+
+func (l *localDaemon) ImageRemove(ctx context.Context, image string, opts types.ImageRemoveOptions) ([]types.ImageDeleteResponseItem, error) {
+	return l.apiClient.ImageRemove(ctx, image, opts)
+}
+
 func getDigest(img string) string {
 	ref, _ := name.NewDigest(img, name.WeakValidation)
 	return ref.DigestStr()

pkg/skaffold/plugin/environments/gcb/types.go

@@ -88,5 +88,5 @@ func (b *Builder) DependenciesForArtifact(ctx context.Context, a *latest.Artifac
 }
 
 func (b *Builder) Prune(ctx context.Context, out io.Writer) error {
-	return nil
+	return nil // noop
 }

pkg/skaffold/plugin/shared/server.go

@@ -47,7 +47,7 @@ func (b *BuilderRPC) Init(opts *config.SkaffoldOptions, env *latest.ExecutionEnv
 	b.client.Call("Plugin.Init", args, &resp)
 }
 
-func (b *BuilderRPC) DependenciesForArtifact(ctx context.Context, artifact *latest.Artifact) ([]string, error) {
+func (b *BuilderRPC) DependenciesForArtifact(_ context.Context, artifact *latest.Artifact) ([]string, error) {
 	var resp []string
 	if err := convertPropertiesToBytes([]*latest.Artifact{artifact}); err != nil {
 		return nil, errors.Wrapf(err, "converting properties to bytes")
@@ -70,7 +70,7 @@ func (b *BuilderRPC) Labels() map[string]string {
 	return resp
 }
 
-func (b *BuilderRPC) Build(ctx context.Context, out io.Writer, tags tag.ImageTags, artifacts []*latest.Artifact) ([]build.Artifact, error) {
+func (b *BuilderRPC) Build(_ context.Context, _ io.Writer, tags tag.ImageTags, artifacts []*latest.Artifact) ([]build.Artifact, error) {
 	var resp []build.Artifact
 	if err := convertPropertiesToBytes(artifacts); err != nil {
 		return nil, errors.Wrapf(err, "converting properties to bytes")
@@ -86,6 +86,14 @@ func (b *BuilderRPC) Build(ctx context.Context, out io.Writer, tags tag.ImageTag
 	return resp, nil
 }
 
+func (b *BuilderRPC) Prune(_ context.Context, _ io.Writer) error {
+	var resp error
+	if err := b.client.Call("Plugin.Prune", new(interface{}), &resp); err != nil {
+		return err
+	}
+	return resp
+}
+
 func convertPropertiesToBytes(artifacts []*latest.Artifact) error {
 	for _, a := range artifacts {
 		if a.BuilderPlugin.Properties == nil {

pkg/skaffold/runner/runner.go

@@ -150,7 +150,7 @@ func getBuilder(cfg *latest.BuildConfig, kubeContext string, opts *config.Skaffo
 
 	case cfg.LocalBuild != nil:
 		logrus.Debugln("Using builder: local")
-		return local.NewBuilder(cfg.LocalBuild, kubeContext, opts.NoPrune, opts.SkipTests)
+		return local.NewBuilder(cfg.LocalBuild, kubeContext, opts.Prune, opts.SkipTests)
 
 	case cfg.GoogleCloudBuild != nil:
 		logrus.Debugln("Using builder: google cloud")
@@ -331,6 +331,7 @@ func (r *SkaffoldRunner) BuildAndTest(ctx context.Context, out io.Writer, artifa
 	if err != nil {
 		return nil, errors.Wrap(err, "build failed")
 	}
+	// TODO(nkubala): prune evicted cache entries here
 	artifactCache.Retag(ctx, out, artifactsToBuild, bRes)
 	bRes = append(bRes, res...)
 	if err := artifactCache.CacheArtifacts(ctx, artifacts, bRes); err != nil {