use v1.Layers (#284)

internal/bundler/apko.go

@@ -10,7 +10,9 @@ import (
 	apko_types "chainguard.dev/apko/pkg/build/types"
 	"chainguard.dev/apko/pkg/tarfs"
 	"github.com/google/go-containerregistry/pkg/name"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/empty"
+	"github.com/google/go-containerregistry/pkg/v1/mutate"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 )
 
@@ -78,7 +80,7 @@ func NewApko(opts ...ApkoOpt) (Bundler, error) {
 	return a, nil
 }
 
-func (a *apko) Bundle(ctx context.Context, repo name.Repository, layers ...Layerer) (name.Reference, error) {
+func (a *apko) Bundle(ctx context.Context, repo name.Repository, layers ...v1.Layer) (name.Reference, error) {
 	bopts := []apko_build.Option{
 		apko_build.WithImageConfiguration(a.apkoConfig),
 		apko_build.WithArch(a.arch),
@@ -105,7 +107,7 @@ func (a *apko) Bundle(ctx context.Context, repo name.Repository, layers ...Layer
 		return nil, fmt.Errorf("failed to build image: %w", err)
 	}
 
-	img, err := appendLayers(base, layers...)
+	img, err := mutate.AppendLayers(base, layers...)
 	if err != nil {
 		return nil, fmt.Errorf("failed to append layers: %w", err)
 	}

internal/bundler/append.go

@@ -13,12 +13,16 @@ import (
 
 type AppendOpts struct {
 	RemoteOptions []remote.Option
-	Layers        []Layerer
+	Layers        []v1.Layer
 	Envs          map[string]string
+	Cmd           string
+	Entrypoint    []string
 }
 
-func Append(ctx context.Context, source name.Reference, target name.Repository, opts AppendOpts) (name.Reference, error) {
-	desc, err := remote.Get(source, opts.RemoteOptions...)
+// Append mutates the source Image or ImageIndex with the provided append
+// options, and pushes it to the target repository via its digest.
+func Append(ctx context.Context, base name.Reference, target name.Repository, opts AppendOpts) (name.Reference, error) {
+	desc, err := remote.Get(base, opts.RemoteOptions...)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get image: %w", err)
 	}
@@ -42,12 +46,7 @@ func Append(ctx context.Context, source name.Reference, target name.Repository,
 				return nil, fmt.Errorf("failed to load image: %w", err)
 			}
 
-			mutated, err := appendLayers(baseimg, opts.Layers...)
-			if err != nil {
-				return nil, err
-			}
-
-			mutated, err = mutateConfig(mutated, opts.Envs)
+			mutated, err := appendToImage(ctx, baseimg, opts)
 			if err != nil {
 				return nil, err
 			}
@@ -86,17 +85,12 @@ func Append(ctx context.Context, source name.Reference, target name.Repository,
 		return ref, nil
 
 	} else if desc.MediaType.IsImage() {
-		baseimg, err := remote.Image(source, opts.RemoteOptions...)
+		baseimg, err := remote.Image(base, opts.RemoteOptions...)
 		if err != nil {
 			return nil, fmt.Errorf("failed to get image: %w", err)
 		}
 
-		mutated, err := appendLayers(baseimg, opts.Layers...)
-		if err != nil {
-			return nil, err
-		}
-
-		mutated, err = mutateConfig(mutated, opts.Envs)
+		mutated, err := appendToImage(ctx, baseimg, opts)
 		if err != nil {
 			return nil, err
 		}
@@ -117,7 +111,21 @@ func Append(ctx context.Context, source name.Reference, target name.Repository,
 	return nil, fmt.Errorf("unsupported media type: %s", desc.MediaType)
 }
 
-func mutateConfig(img v1.Image, envs map[string]string) (v1.Image, error) {
+func appendToImage(_ context.Context, img v1.Image, opts AppendOpts) (v1.Image, error) {
+	mutated, err := mutate.AppendLayers(img, opts.Layers...)
+	if err != nil {
+		return nil, err
+	}
+
+	mutated, err = mutateConfig(mutated, opts.Envs, opts.Entrypoint, opts.Cmd)
+	if err != nil {
+		return nil, err
+	}
+
+	return mutated, nil
+}
+
+func mutateConfig(img v1.Image, envs map[string]string, entrypoint []string, cmd string) (v1.Image, error) {
 	cfg, err := img.ConfigFile()
 	if err != nil {
 		return nil, fmt.Errorf("failed to get config file: %w", err)
@@ -127,5 +135,13 @@ func mutateConfig(img v1.Image, envs map[string]string) (v1.Image, error) {
 		cfg.Config.Env = append(cfg.Config.Env, fmt.Sprintf("%s=%s", k, v))
 	}
 
+	if cmd != "" {
+		cfg.Config.Cmd = []string{cmd}
+	}
+
+	if len(entrypoint) > 0 {
+		cfg.Config.Entrypoint = entrypoint
+	}
+
 	return mutate.ConfigFile(img, cfg)
 }

internal/bundler/appender.go

@@ -4,6 +4,7 @@ import (
 	"context"
 
 	"github.com/google/go-containerregistry/pkg/name"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 )
 
@@ -30,7 +31,7 @@ func NewAppender(base name.Reference, opts ...AppenderOpt) (Bundler, error) {
 	return a, nil
 }
 
-func (a *appender) Bundle(ctx context.Context, repo name.Repository, layers ...Layerer) (name.Reference, error) {
+func (a *appender) Bundle(ctx context.Context, repo name.Repository, layers ...v1.Layer) (name.Reference, error) {
 	opts := AppendOpts{
 		RemoteOptions: a.ropts,
 		Layers:        layers,

internal/bundler/bundler.go

@@ -4,8 +4,9 @@ import (
 	"context"
 
 	"github.com/google/go-containerregistry/pkg/name"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
 )
 
 type Bundler interface {
-	Bundle(ctx context.Context, repo name.Repository, layers ...Layerer) (name.Reference, error)
+	Bundle(ctx context.Context, repo name.Repository, layers ...v1.Layer) (name.Reference, error)
 }

internal/bundler/layer.go

@@ -4,32 +4,16 @@ import (
 	"archive/tar"
 	"io"
 	"io/fs"
-	"path/filepath"
+	"os"
+	"path"
 
+	"chainguard.dev/apko/pkg/tarfs"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
-	"github.com/google/go-containerregistry/pkg/v1/mutate"
 	"github.com/google/go-containerregistry/pkg/v1/tarball"
 )
 
-type Layerer interface {
-	Layer() (v1.Layer, error)
-}
-
-var _ Layerer = &fsl{}
-
-type fsl struct {
-	source fs.FS
-	target string
-}
-
-func NewFSLayer(source fs.FS, target string) Layerer {
-	return &fsl{
-		source: source,
-		target: target,
-	}
-}
-
-func (l *fsl) Layer() (v1.Layer, error) {
+// NewLayerFromFS creates a v1.Layer from a filesystem and target path.
+func NewLayerFromFS(source fs.FS, target string) (v1.Layer, error) {
 	return tarball.LayerFromOpener(func() (io.ReadCloser, error) {
 		pr, pw := io.Pipe()
 
@@ -38,7 +22,7 @@ func (l *fsl) Layer() (v1.Layer, error) {
 			defer tw.Close()
 			defer pw.Close()
 
-			if err := fs.WalkDir(l.source, ".", func(path string, d fs.DirEntry, err error) error {
+			if err := fs.WalkDir(source, ".", func(p string, d fs.DirEntry, err error) error {
 				if err != nil {
 					return err
 				}
@@ -53,14 +37,14 @@ func (l *fsl) Layer() (v1.Layer, error) {
 					return err
 				}
 
-				hdr.Name = filepath.Join(l.target, path)
+				hdr.Name = path.Join(target, p)
 
 				if err := tw.WriteHeader(hdr); err != nil {
 					return err
 				}
 
 				if !d.IsDir() {
-					f, err := l.source.Open(path)
+					f, err := source.Open(p)
 					if err != nil {
 						return err
 					}
@@ -82,19 +66,27 @@ func (l *fsl) Layer() (v1.Layer, error) {
 	})
 }
 
-func appendLayers(img v1.Image, layers ...Layerer) (v1.Image, error) {
-	mutated := img
+// NewLayerFromPath creates a v1.Layer from a local path.
+func NewLayerFromPath(source string, target string) (v1.Layer, error) {
+	pi, err := os.Stat(source)
+	if err != nil {
+		return nil, err
+	}
+
+	if pi.IsDir() {
+		return NewLayerFromFS(os.DirFS(source), target)
+	}
 
-	for _, l := range layers {
-		layer, err := l.Layer()
-		if err != nil {
-			return nil, err
-		}
+	// Handle single file
+	data, err := os.ReadFile(source)
+	if err != nil {
+		return nil, err
+	}
 
-		mutated, err = mutate.AppendLayers(mutated, layer)
-		if err != nil {
-			return nil, err
-		}
+	tfs := tarfs.New()
+	if err := tfs.WriteFile(pi.Name(), data, pi.Mode()); err != nil {
+		return nil, err
 	}
-	return mutated, nil
+
+	return NewLayerFromFS(tfs, target)
 }

internal/provider/harness_docker_resource.go

@@ -14,6 +14,7 @@ import (
 	"github.com/chainguard-dev/terraform-provider-imagetest/internal/provider/framework"
 	"github.com/docker/docker/api/types/mount"
 	"github.com/google/go-containerregistry/pkg/name"
+	ggcrv1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/hashicorp/terraform-plugin-framework/diag"
 	"github.com/hashicorp/terraform-plugin-framework/resource"
 	"github.com/hashicorp/terraform-plugin-framework/resource/schema"
@@ -210,12 +211,16 @@ func (r *HarnessDockerResource) harness(ctx context.Context, data *HarnessDocker
 		return nil, []diag.Diagnostic{diag.NewErrorDiagnostic("failed to create bundler", err.Error())}
 	}
 
-	var layers []bundler.Layerer
+	var layers []ggcrv1.Layer
 	for _, sl := range data.Layers {
-		layers = append(layers, bundler.NewFSLayer(
+		layer, err := bundler.NewLayerFromFS(
 			os.DirFS(sl.Source.ValueString()),
 			sl.Target.ValueString(),
-		))
+		)
+		if err != nil {
+			return nil, []diag.Diagnostic{diag.NewErrorDiagnostic("failed to create layer", err.Error())}
+		}
+		layers = append(layers, layer)
 	}
 
 	bref, err := b.Bundle(ctx, r.store.repo, layers...)

internal/provider/harness_k3s_resource.go

@@ -14,6 +14,7 @@ import (
 	"github.com/chainguard-dev/terraform-provider-imagetest/internal/provider/framework"
 	"github.com/docker/docker/api/types/mount"
 	"github.com/google/go-containerregistry/pkg/name"
+	ggcrv1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/hashicorp/terraform-plugin-framework/diag"
 	"github.com/hashicorp/terraform-plugin-framework/resource"
 	"github.com/hashicorp/terraform-plugin-framework/resource/schema"
@@ -167,16 +168,17 @@ func (r *HarnessK3sResource) harness(ctx context.Context, data *HarnessK3sResour
 		return nil, []diag.Diagnostic{diag.NewErrorDiagnostic("failed to create bundler", err.Error())}
 	}
 
-	var ls []bundler.Layerer
+	var ls []ggcrv1.Layer
 
 	if sandbox := data.Sandbox; sandbox != nil {
 		log.Info(ctx, "parsing sandbox", "raw", sandbox)
 
 		for _, l := range sandbox.Layers {
-			ls = append(ls, bundler.NewFSLayer(
-				os.DirFS(l.Source.ValueString()),
-				l.Target.ValueString(),
-			))
+			layer, err := bundler.NewLayerFromPath(l.Source.ValueString(), l.Target.ValueString())
+			if err != nil {
+				return nil, []diag.Diagnostic{diag.NewErrorDiagnostic("failed to create layer", err.Error())}
+			}
+			ls = append(ls, layer)
 		}
 
 		for _, m := range sandbox.Mounts {