CLI to get binaries from a docker image with multi arch support

have a look at the README.md to see how it works.

Bootstrap a CLI program to copy binaries from multi arch images

Signed-off-by: Gianluca Arbezzano <gianarb92@gmail.com>

cmd/getbinariesfromquay/docker/image.go

@@ -0,0 +1,76 @@
+package docker
+
+import (
+	"context"
+
+	"github.com/containers/image/v5/copy"
+	"github.com/containers/image/v5/manifest"
+	"github.com/containers/image/v5/signature"
+	"github.com/containers/image/v5/transports/alltransports"
+	"github.com/containers/image/v5/types"
+)
+
+type Image struct {
+	src types.ImageSource
+	ref types.ImageReference
+	sys *types.SystemContext
+}
+
+func ImageFromName(ctx context.Context, sys *types.SystemContext, name string) (*Image, error) {
+	imageRef, err := alltransports.ParseImageName(name)
+	if err != nil {
+		return nil, err
+	}
+	src, err := imageRef.NewImageSource(ctx, sys)
+	if err != nil {
+		return nil, err
+	}
+	return &Image{
+		src: src,
+		ref: imageRef,
+		sys: sys,
+	}, nil
+}
+
+func (img *Image) GetManifest(ctx context.Context) ([]byte, string, error) {
+	rawManifest, _, err := img.src.GetManifest(ctx, nil)
+	if err != nil {
+		return nil, "", err
+	}
+	return rawManifest, manifest.GuessMIMEType(rawManifest), nil
+}
+
+func (img *Image) Copy(ctx context.Context, dst string) error {
+	destRef, err := alltransports.ParseImageName(dst)
+	if err != nil {
+		return err
+	}
+	pc, err := signature.NewPolicyContext(&signature.Policy{
+		Default: []signature.PolicyRequirement{
+			signature.NewPRInsecureAcceptAnything(),
+		},
+	})
+	if err != nil {
+		return err
+	}
+	_, err = copy.Image(ctx, pc, destRef, img.ref, &copy.Options{SourceCtx: img.sys})
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+type SchemaV2List struct {
+	MediaType     string `json:"mediaType"`
+	SchemaVersion int    `json:"schemaVersion"`
+	Manifests     []struct {
+		MediaType string `json:"mediaType"`
+		Digest    string `json:"digest"`
+		Size      int    `json:"size"`
+		Platform  struct {
+			Architecture string `json:"architecture"`
+			Os           string `json:"os"`
+			Variant      string `json:"variant"`
+		} `json:"platform,omitempty"`
+	} `json:"manifests"`
+}