prefer relative access for uploader

- use relative access methods for OCI upload to
  local OCM repository
- make preference configurable for repos

Author: mandelsoft

api/config/utils.go

@@ -0,0 +1,18 @@
+package config
+
+import (
+	cfgcpi "ocm.software/ocm/api/config/cpi"
+)
+
+// GetConfigured applies config objects of a config context
+// to a configuration struct of type T.
+// A pointer to the configured struct is returned.
+// Attention: T must be a struct type.
+func GetConfigured[T any](ctxp ContextProvider) (*T, error) {
+	var c T
+	err := cfgcpi.NewUpdater(ctxp.ConfigContext(), &c).Update()
+	if err != nil {
+		return nil, err
+	}
+	return &c, nil
+}

api/oci/interface.go

@@ -38,6 +38,8 @@ type (
 	BlobAccess                       = internal.BlobAccess
 	DataAccess                       = internal.DataAccess
 	ConsumerIdentityProvider         = internal.ConsumerIdentityProvider
+
+	UniformRepositorySpecProvider = internal.UniformRepositorySpecProvider
 )
 
 func DefaultContext() internal.Context {

api/oci/internal/repotypes.go

@@ -20,11 +20,15 @@ type IntermediateRepositorySpecAspect interface {
 	IsIntermediate() bool
 }
 
+type UniformRepositorySpecProvider interface {
+	UniformRepositorySpec() *UniformRepositorySpec
+}
+
 type RepositorySpec interface {
 	runtime.VersionedTypedObject
+	UniformRepositorySpecProvider
 
 	Name() string
-	UniformRepositorySpec() *UniformRepositorySpec
 	Repository(Context, credentials.Credentials) (Repository, error)
 
 	Validate(Context, credentials.Credentials, ...credentials.UsageContext) error

api/ocm/extensions/accessmethods/relativeociref/method.go

@@ -24,7 +24,7 @@ func init() {
 
 var _ accspeccpi.HintProvider = (*AccessSpec)(nil)
 
-// New creates a new localFilesystemBlob accessor.
+// New creates a new relativeOciReference accessor.
 func New(ref string) *AccessSpec {
 	return &AccessSpec{
 		ObjectVersionedType: runtime.NewVersionedObjectType(Type),
@@ -82,7 +82,20 @@ func (a *AccessSpec) GetOCIReference(cv accspeccpi.ComponentVersionAccess) (stri
 	defer m.Close()
 
 	if o, ok := accspeccpi.GetAccessMethodImplementation(m).(ociartifact.OCIArtifactReferenceProvider); ok {
-		return o.GetOCIReference(nil)
+		im, err := o.GetOCIReference(cv)
+		if err == nil {
+			if s, ok := cv.Repository().GetSpecification().(oci.UniformRepositorySpecProvider); ok {
+				host := s.UniformRepositorySpec().Host
+				// not supported for fake repos
+				if host != "" {
+					im = host + "/" + im
+				}
+			}
+		}
+		return im, err
 	}
 	return "", nil
 }
+
+type specprovider interface {
+}

api/ocm/extensions/attrs/preferrelativeattr/attr.go

@@ -0,0 +1,66 @@
+package preferrelativeattr
+
+import (
+	"fmt"
+
+	"ocm.software/ocm/api/datacontext"
+	"ocm.software/ocm/api/utils/runtime"
+)
+
+const (
+	ATTR_KEY   = "github.com/mandelsoft/ocm/preferrelativeaccess"
+	ATTR_SHORT = "preferrelativeaccess"
+)
+
+func init() {
+	datacontext.RegisterAttributeType(ATTR_KEY, AttributeType{}, ATTR_SHORT)
+}
+
+type AttributeType struct{}
+
+func (a AttributeType) Name() string {
+	return ATTR_KEY
+}
+
+func (a AttributeType) Description() string {
+	return `
+*bool*
+If an artifact blob is uploaded to the technical repository
+used as OCM repository, the uploader should prefer to return
+a relative access method.
+`
+}
+
+func (a AttributeType) Encode(v interface{}, marshaller runtime.Marshaler) ([]byte, error) {
+	if _, ok := v.(bool); !ok {
+		return nil, fmt.Errorf("boolean required")
+	}
+	return marshaller.Marshal(v)
+}
+
+func (a AttributeType) Decode(data []byte, unmarshaller runtime.Unmarshaler) (interface{}, error) {
+	var value bool
+	err := unmarshaller.Unmarshal(data, &value)
+	return value, err
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+func Get(ctx datacontext.Context) bool {
+	a := ctx.GetAttributes().GetAttribute(ATTR_KEY)
+	if a == nil {
+		return false
+	}
+	return a.(bool)
+}
+
+func Set(ctx datacontext.Context, flag bool) error {
+	return ctx.GetAttributes().SetAttribute(ATTR_KEY, flag)
+}
+
+func ApplyTo(ctx datacontext.Context, flag *bool) bool {
+	if a := ctx.GetAttributes().GetAttribute(ATTR_KEY); a != nil {
+		*flag = a.(bool)
+	}
+	return *flag
+}

api/ocm/extensions/attrs/preferrelativeattr/attr_test.go

@@ -0,0 +1,41 @@
+package preferrelativeattr_test
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"ocm.software/ocm/api/config"
+	"ocm.software/ocm/api/credentials"
+	"ocm.software/ocm/api/datacontext"
+	"ocm.software/ocm/api/oci"
+	"ocm.software/ocm/api/ocm"
+	me "ocm.software/ocm/api/ocm/extensions/attrs/keepblobattr"
+	"ocm.software/ocm/api/utils/runtime"
+)
+
+var _ = Describe("attribute", func() {
+	var ctx ocm.Context
+	var cfgctx config.Context
+
+	BeforeEach(func() {
+		cfgctx = config.WithSharedAttributes(datacontext.New(nil)).New()
+		credctx := credentials.WithConfigs(cfgctx).New()
+		ocictx := oci.WithCredentials(credctx).New()
+		ctx = ocm.WithOCIRepositories(ocictx).New()
+	})
+	It("local setting", func() {
+		Expect(me.Get(ctx)).To(BeFalse())
+		Expect(me.Set(ctx, true)).To(Succeed())
+		Expect(me.Get(ctx)).To(BeTrue())
+	})
+
+	It("global setting", func() {
+		Expect(me.Get(cfgctx)).To(BeFalse())
+		Expect(me.Set(ctx, true)).To(Succeed())
+		Expect(me.Get(ctx)).To(BeTrue())
+	})
+
+	It("parses string", func() {
+		Expect(me.AttributeType{}.Decode([]byte("true"), runtime.DefaultJSONEncoding)).To(BeTrue())
+	})
+})

api/ocm/extensions/attrs/preferrelativeattr/suite_test.go

@@ -0,0 +1,13 @@
+package preferrelativeattr_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestConfig(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "OCM Prefer Relative Access Attribute")
+}

api/ocm/extensions/blobhandler/handlers/oci/ocirepo/blobhandler.go

@@ -6,6 +6,10 @@ import (
 	"strings"
 
 	. "github.com/mandelsoft/goutils/finalizer"
+	cfgctx "ocm.software/ocm/api/config"
+	"ocm.software/ocm/api/ocm/extensions/accessmethods/relativeociref"
+	"ocm.software/ocm/api/ocm/extensions/attrs/preferrelativeattr"
+	"ocm.software/ocm/api/ocm/extensions/blobhandler/handlers/oci/ocirepo/config"
 
 	"github.com/mandelsoft/goutils/errors"
 	"github.com/mandelsoft/goutils/sliceutils"
@@ -226,6 +230,14 @@ func (b *artifactHandler) StoreBlob(blob cpi.BlobAccess, artType, hint string, g
 
 	keep := keepblobattr.Get(ctx.GetContext())
 
+	opts, _ := cfgctx.GetConfigured[config.UploadOptions](ctx.GetContext())
+	if opts == nil {
+		opts = &config.UploadOptions{}
+	}
+	// this attribute (only if set) overrides the enabling set in the
+	// config.
+	preferrelativeattr.ApplyTo(ctx.GetContext(), &opts.PreferRelativeAccess)
+
 	if m, ok := blob.(blobaccess.AnnotatedBlobAccess[accspeccpi.AccessMethodView]); ok {
 		// prepare for optimized point to point implementation
 		log.Debug("oci artifact handler with ocm access source",
@@ -340,6 +352,10 @@ func (b *artifactHandler) StoreBlob(blob cpi.BlobAccess, artType, hint string, g
 	if tag != "" {
 		tag = ":" + tag
 	}
+	if opts.PreferRelativeAccessFor(base) {
+		ref := namespace.GetNamespace() + tag + version
+		return relativeociref.New(ref), nil
+	}
 	ref := scheme + path.Join(base, namespace.GetNamespace()) + tag + version
 	return ociartifact.New(ref), nil
 }

api/ocm/extensions/blobhandler/handlers/oci/ocirepo/config/option.go

@@ -0,0 +1,49 @@
+package config
+
+import (
+	"net"
+)
+
+// UploadOptions is used to configure
+// the implicit OCI uploader for a local OCM repository.
+// It can be used to request the generation of relative
+// OCI access methods, generally or for dedicated targets.
+type UploadOptions struct {
+	// PreferRelativeAccess enables or disables the settings.
+	PreferRelativeAccess bool `json:"preferRelativeAccess,omitempty"`
+	// Repositories is list of repository specs, with or without port.
+	// If no filters are configured all repos are matched.
+	Repositories []string `json:"repositories,omitempty"`
+}
+
+// PreferRelativeAccessFor checks a repo spec for using
+// a relative access method instead of an absolute one.
+// It checks hostname and optionally a port name.
+// The most specific configuration wins.
+func (o *UploadOptions) PreferRelativeAccessFor(repo string) bool {
+	if len(o.Repositories) == 0 || !o.PreferRelativeAccess {
+		return o.PreferRelativeAccess
+	}
+
+	fallback := false
+
+	host, port, err := net.SplitHostPort(repo)
+	if err != nil {
+		host = repo
+	}
+	for _, r := range o.Repositories {
+		rhost, rport, err := net.SplitHostPort(r)
+		if err != nil {
+			rhost = r
+		}
+		if host == rhost {
+			if rport == "" {
+				fallback = true
+			}
+			if port == rport {
+				return true
+			}
+		}
+	}
+	return fallback
+}

api/ocm/extensions/blobhandler/handlers/oci/ocirepo/config/suite_test.go

@@ -0,0 +1,13 @@
+package config_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestConfig(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "OCI Uploader forOCI OCM Repositories Test Suite")
+}