blueprint downloader (#375)

* initial implementation of a blueprint downloader

* add tests for download and registration

* utilize printer within downloader implementation

* fix linter issues

* fix linter issues

---------

Co-authored-by: Gerald Morrison <67469729+morri-son@users.noreply.github.com>

pkg/contexts/oci/artdesc/utils.go

@@ -60,6 +60,11 @@ func ToDescriptorMediaType(media string) string {
 	return ToContentMediaType(media) + "+json"
 }
 
+func ToArchiveMediaTypes(media string) []string {
+	base := ToContentMediaType(media)
+	return []string{base + "+tar", base + "+tar+gzip"}
+}
+
 func IsOCIMediaType(media string) bool {
 	c := ToContentMediaType(media)
 	for _, t := range ContentTypes() {
@@ -90,8 +95,7 @@ func DescriptorTypes() []string {
 func ArchiveBlobTypes() []string {
 	r := []string{}
 	for _, t := range ContentTypes() {
-		t = ToContentMediaType(t)
-		r = append(r, t+"+tar", t+"+tar+gzip")
+		r = append(r, ToArchiveMediaTypes(t)...)
 	}
 	return r
 }

pkg/contexts/ocm/download/handlers/blueprint/blueprint_test.go

@@ -0,0 +1,106 @@
+// SPDX-FileCopyrightText: 2023 SAP SE or an SAP affiliate company and Open Component Model contributors.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package blueprint_test
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	. "github.com/open-component-model/ocm/pkg/env/builder"
+	. "github.com/open-component-model/ocm/pkg/testutils"
+
+	"github.com/mandelsoft/vfs/pkg/projectionfs"
+
+	"github.com/open-component-model/ocm/pkg/common"
+	"github.com/open-component-model/ocm/pkg/common/accessio"
+	"github.com/open-component-model/ocm/pkg/common/accessobj"
+	"github.com/open-component-model/ocm/pkg/contexts/oci/testhelper"
+	"github.com/open-component-model/ocm/pkg/contexts/ocm/accessmethods/ociartifact"
+	v1 "github.com/open-component-model/ocm/pkg/contexts/ocm/compdesc/meta/v1"
+	"github.com/open-component-model/ocm/pkg/contexts/ocm/download"
+	"github.com/open-component-model/ocm/pkg/contexts/ocm/download/handlers/blueprint"
+	ctfocm "github.com/open-component-model/ocm/pkg/contexts/ocm/repositories/ctf"
+	tenv "github.com/open-component-model/ocm/pkg/env"
+	"github.com/open-component-model/ocm/pkg/utils/tarutils"
+)
+
+const (
+	COMPONENT = "github.com/compa"
+	VERSION   = "1.0.0"
+	CTF       = "ctf"
+	OCI       = "oci"
+
+	OCIHOST      = "source"
+	OCINAMESPACE = "ocm/value"
+	OCIVERSION   = "v2.0"
+
+	MIMETYPE            = "testmimetype"
+	ARTIFACT_TYPE       = "testartifacttype"
+	OCI_ARTIFACT_NAME   = "ociblueprint"
+	LOCAL_ARTIFACT_NAME = "localblueprint"
+	ARTIFACT_VERSION    = "v1.0.0"
+
+	TESTDATA_PATH = "testdata/blueprint"
+	ARCHIVE_PATH  = "archive"
+	DOWNLOAD_PATH = "download"
+)
+
+var _ = Describe("download blueprint", func() {
+	var env *Builder
+
+	BeforeEach(func() {
+		env = NewBuilder(tenv.NewEnvironment(tenv.TestData()))
+
+		MustBeSuccessful(tarutils.CreateTarFromFs(Must(projectionfs.New(env, TESTDATA_PATH)), ARCHIVE_PATH, tarutils.Gzip, env))
+
+		env.OCICommonTransport(OCI, accessio.FormatDirectory, func() {
+			env.Namespace(OCINAMESPACE, func() {
+				env.Manifest(OCIVERSION, func() {
+					env.Config(func() {
+						env.BlobStringData(blueprint.CONFIG_MIME_TYPE, "{}")
+					})
+					env.Layer(func() {
+						env.BlobFromFile(blueprint.BLUEPRINT_MIMETYPE, ARCHIVE_PATH)
+					})
+				})
+			})
+		})
+
+		testhelper.FakeOCIRepo(env, OCI, OCIHOST)
+		env.OCMCommonTransport(CTF, accessio.FormatDirectory, func() {
+			env.ComponentVersion(COMPONENT, VERSION, func() {
+				env.Resource(OCI_ARTIFACT_NAME, ARTIFACT_VERSION, blueprint.TYPE, v1.ExternalRelation, func() {
+					env.Access(ociartifact.New(OCIHOST + ".alias/" + OCINAMESPACE + ":" + OCIVERSION))
+				})
+				env.Resource(LOCAL_ARTIFACT_NAME, ARTIFACT_VERSION, blueprint.TYPE, v1.LocalRelation, func() {
+					env.BlobFromFile(blueprint.BLUEPRINT_MIMETYPE, ARCHIVE_PATH)
+				})
+			})
+		})
+	})
+
+	AfterEach(func() {
+		env.Cleanup()
+	})
+	DescribeTable("download blueprints", func(index int) {
+		src := Must(ctfocm.Open(env.OCMContext(), accessobj.ACC_READONLY, CTF, 0, env))
+		defer Close(src, "source ctf")
+
+		cv := Must(src.LookupComponentVersion(COMPONENT, VERSION))
+		defer Close(cv)
+
+		racc := Must(cv.GetResourceByIndex(index))
+
+		p, buf := common.NewBufferedPrinter()
+		ok, path := Must2(download.For(env).Download(p, racc, DOWNLOAD_PATH, env))
+		Expect(ok).To(BeTrue())
+		Expect(path).To(Equal(DOWNLOAD_PATH))
+		Expect(env.FileExists(DOWNLOAD_PATH + "/blueprint.yaml")).To(BeTrue())
+		Expect(env.FileExists(DOWNLOAD_PATH + "/test/README.md")).To(BeTrue())
+		Expect(buf.String()).To(StringEqualTrimmedWithContext(DOWNLOAD_PATH + ": 2 file(s) with 390 byte(s) written"))
+	},
+		Entry("oci artifact", 0),
+		Entry("local resource", 1),
+	)
+})

pkg/contexts/ocm/download/handlers/blueprint/extrator.go

@@ -0,0 +1,92 @@
+// SPDX-FileCopyrightText: 2023 SAP SE or an SAP affiliate company and Open Component Model contributors.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package blueprint
+
+import (
+	"github.com/mandelsoft/vfs/pkg/projectionfs"
+	"github.com/mandelsoft/vfs/pkg/vfs"
+
+	"github.com/open-component-model/ocm/pkg/common"
+	"github.com/open-component-model/ocm/pkg/common/accessio"
+	"github.com/open-component-model/ocm/pkg/common/accessobj"
+	"github.com/open-component-model/ocm/pkg/common/compression"
+	"github.com/open-component-model/ocm/pkg/contexts/oci/repositories/artifactset"
+	"github.com/open-component-model/ocm/pkg/finalizer"
+	"github.com/open-component-model/ocm/pkg/utils/tarutils"
+)
+
+const (
+	BLUEPRINT_MIMETYPE_LEGACY = "application/vnd.gardener.landscaper.blueprint.layer.v1.tar"
+	BLUEPRINT_MIMETYPE        = "application/vnd.gardener.landscaper.blueprint.v1+tar+gzip"
+)
+
+func ExtractArchive(pr common.Printer, _ *Handler, access accessio.DataAccess, path string, fs vfs.FileSystem) (_ bool, rerr error) {
+	var finalize finalizer.Finalizer
+	defer finalize.FinalizeWithErrorPropagationf(&rerr, "extracting archived (and compressed) blueprint")
+
+	rawReader, err := access.Reader()
+	if err != nil {
+		return true, err
+	}
+	finalize.Close(rawReader)
+
+	reader, _, err := compression.AutoDecompress(rawReader)
+	if err != nil {
+		return true, err
+	}
+	finalize.Close(reader)
+
+	err = fs.MkdirAll(path, 0o700)
+	if err != nil {
+		return true, err
+	}
+
+	pfs, err := projectionfs.New(fs, path)
+	if err != nil {
+		return true, err
+	}
+	fcnt, bcnt, err := tarutils.ExtractTarToFsWithInfo(pfs, reader)
+	if err != nil {
+		return true, err
+	}
+	pr.Printf("%s: %d file(s) with %d byte(s) written\n", path, fcnt, bcnt)
+	return true, nil
+}
+
+func ExtractArtifact(pr common.Printer, handler *Handler, access accessio.DataAccess, path string, fs vfs.FileSystem) (_ bool, rerr error) {
+	var finalize finalizer.Finalizer
+	defer finalize.FinalizeWithErrorPropagationf(&rerr, "extracting oci artifact containing a blueprint")
+
+	rd, err := access.Reader()
+	if err != nil {
+		return true, err
+	}
+	finalize.Close(rd)
+
+	set, err := artifactset.Open(accessobj.ACC_READONLY, "", 0, accessio.Reader(rd))
+	if err != nil {
+		return true, err
+	}
+	finalize.Close(set)
+
+	art, err := set.GetArtifact(set.GetMain().String())
+	if err != nil {
+		return true, err
+	}
+	finalize.Close(art)
+
+	desc := art.ManifestAccess().GetDescriptor().Layers[0]
+	if !handler.ociConfigMimeTypes.Contains(art.ManifestAccess().GetDescriptor().Config.MediaType) {
+		if desc.MediaType != BLUEPRINT_MIMETYPE && desc.MediaType != BLUEPRINT_MIMETYPE_LEGACY {
+			return false, nil
+		}
+	}
+
+	blob, err := art.GetBlob(desc.Digest)
+	if err != nil {
+		return true, err
+	}
+	return ExtractArchive(pr, handler, blob, path, fs)
+}

pkg/contexts/ocm/download/handlers/blueprint/handler.go

@@ -0,0 +1,86 @@
+// SPDX-FileCopyrightText: 2022 SAP SE or an SAP affiliate company and Open Component Model contributors.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package blueprint
+
+import (
+	"github.com/mandelsoft/vfs/pkg/vfs"
+
+	"github.com/open-component-model/ocm/pkg/common"
+	"github.com/open-component-model/ocm/pkg/common/accessio"
+	"github.com/open-component-model/ocm/pkg/contexts/oci/artdesc"
+	"github.com/open-component-model/ocm/pkg/contexts/ocm/cpi"
+	registry "github.com/open-component-model/ocm/pkg/contexts/ocm/download"
+	"github.com/open-component-model/ocm/pkg/contexts/ocm/resourcetypes"
+	"github.com/open-component-model/ocm/pkg/finalizer"
+	"github.com/open-component-model/ocm/pkg/generics"
+	"github.com/open-component-model/ocm/pkg/mime"
+	"github.com/open-component-model/ocm/pkg/utils"
+)
+
+const (
+	TYPE             = resourcetypes.BLUEPRINT
+	LEGACY_TYPE      = resourcetypes.BLUEPRINT_LEGACY
+	CONFIG_MIME_TYPE = "application/vnd.gardener.landscaper.blueprint.config.v1"
+)
+
+type Extractor func(pr common.Printer, handler *Handler, access accessio.DataAccess, path string, fs vfs.FileSystem) (bool, error)
+
+var (
+	supportedArtifactTypes    []string
+	mimeTypeExtractorRegistry map[string]Extractor
+)
+
+type Handler struct {
+	ociConfigMimeTypes generics.Set[string]
+}
+
+func init() {
+	supportedArtifactTypes = []string{TYPE, LEGACY_TYPE}
+	mimeTypeExtractorRegistry = map[string]Extractor{
+		mime.MIME_TAR:      ExtractArchive,
+		mime.MIME_TGZ:      ExtractArchive,
+		mime.MIME_TGZ_ALT:  ExtractArchive,
+		BLUEPRINT_MIMETYPE: ExtractArchive,
+	}
+	for _, t := range append(artdesc.ToArchiveMediaTypes(artdesc.MediaTypeImageManifest), artdesc.ToArchiveMediaTypes(artdesc.MediaTypeDockerSchema2Manifest)...) {
+		mimeTypeExtractorRegistry[t] = ExtractArtifact
+	}
+
+	h := New()
+
+	registry.Register(h, registry.ForArtifactType(TYPE))
+	registry.Register(h, registry.ForArtifactType(LEGACY_TYPE))
+}
+
+func New(configmimetypes ...string) *Handler {
+	if len(configmimetypes) == 0 || utils.Optional(configmimetypes...) == "" {
+		configmimetypes = []string{CONFIG_MIME_TYPE}
+	}
+	return &Handler{
+		ociConfigMimeTypes: generics.NewSet[string](configmimetypes...),
+	}
+}
+
+func (h *Handler) Download(pr common.Printer, racc cpi.ResourceAccess, path string, fs vfs.FileSystem) (_ bool, _ string, err error) {
+	var finalize finalizer.Finalizer
+	defer finalize.FinalizeWithErrorPropagationf(&err, "downloading blueprint")
+
+	meth, err := racc.AccessMethod()
+	if err != nil {
+		return false, "", err
+	}
+	finalize.Close(meth)
+
+	ex := mimeTypeExtractorRegistry[meth.MimeType()]
+	if ex == nil {
+		return false, "", nil
+	}
+
+	ok, err := ex(pr, h, meth, path, fs)
+	if err != nil || !ok {
+		return ok, "", err
+	}
+	return true, path, nil
+}