refactor: refine image tag created time fetch

Author: ttys3

handlers.go

@@ -3,12 +3,8 @@ package main
 import (
 	"bytes"
 	"context"
-	"encoding/json"
-	"errors"
 	"fmt"
-	"github.com/distribution/distribution/v3/manifest/ocischema"
 	"github.com/labstack/echo/v4"
-	ociv1 "github.com/opencontainers/image-spec/specs-go/v1"
 	"html/template"
 	"io/ioutil"
 	"net/http"
@@ -198,47 +194,9 @@ func (rc *registryController) generateTagsTemplate(ctx context.Context, repo str
 		// get the image creat time, for v2 or oci image,
 		// maybe someday we can get it from `org.opencontainers.image.created` annotation
 		// ref https://github.com/opencontainers/image-spec/blob/main/annotations.md#pre-defined-annotation-keys
-		m1, err := rc.reg.ManifestV1(ctx, repo, tag)
-		var createdDate *time.Time
-		var imageType string
+		createdDate, imageType, err := rc.reg.TagCreatedDate(ctx, repo, tag)
 		if err != nil {
-			// skip htp error
-			logrus.Warnf("getting v1 manifest for %s:%s failed: %v, try v2 and oci", repo, tag, err)
-			if errors.Is(err, registry.ErrResourceNotFound) {
-				manifest, descriptor, err := rc.reg.Manifest(ctx, repo, tag)
-				if err != nil {
-					logrus.Errorf("getting v2 or oci manifest for %s:%s failed: %v", repo, tag, err)
-				} else if descriptor.MediaType == ociv1.MediaTypeImageManifest {
-					if ocimanifest, ok := manifest.(*ocischema.DeserializedManifest); ok && ocimanifest.Annotations != nil {
-						if created, ok := ocimanifest.Annotations["org.opencontainers.image.created"]; ok {
-							if t, err := time.Parse(time.RFC3339, created); err == nil {
-								createdDate = &t
-							}
-						}
-					}
-					imageType = "OCI"
-				} else {
-					logrus.Warnf("can not get created time, unsupported manifest type %s for %s:%s",
-						descriptor.MediaType, repo, tag)
-					imageType = "Docker V2"
-				}
-				if createdDate == nil {
-					if created, err := rc.reg.CreatedDate(ctx, repo, manifest.References()[0].Digest); err == nil {
-						createdDate = created
-					}
-				}
-			}
-		} else {
-			for _, h := range m1.History {
-				var comp v1Compatibility
-
-				if err := json.Unmarshal([]byte(h.V1Compatibility), &comp); err != nil {
-					return nil, fmt.Errorf("unmarshal v1 manifest for %s:%s failed: %v", repo, tag, err)
-				}
-				createdDate = &comp.Created
-				imageType = "Docker V1"
-				break
-			}
+			logrus.Warnf("getting created date for %s:%s failed: %v", repo, tag, err)
 		}
 
 		repoURI := fmt.Sprintf("%s/%s", rc.reg.Domain, repo)

registry/tags.go

@@ -2,7 +2,10 @@ package registry
 
 import (
 	"context"
+	"github.com/distribution/distribution/v3/manifest/ocischema"
+	"github.com/distribution/distribution/v3/manifest/schema2"
 	"github.com/opencontainers/go-digest"
+	ociv1 "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/sirupsen/logrus"
 	"time"
 )
@@ -37,3 +40,35 @@ func (r *Registry) CreatedDate(ctx context.Context, repository string, configDig
 	logrus.Infof("Got created time from config layer: %v", configBase.Created)
 	return configBase.Created, nil
 }
+
+func (r *Registry) TagCreatedDate(ctx context.Context, repo, tag string) (createdDate *time.Time, imageType string, retErr error) {
+	imageType = "Docker v1"
+	manifest, descriptor, err := r.Manifest(ctx, repo, tag)
+	if err != nil {
+		logrus.Errorf("getting v2 or oci manifest for %s:%s failed: %v", repo, tag, err)
+		retErr = err
+		return
+	} else if descriptor.MediaType == ociv1.MediaTypeImageManifest {
+		if ocimanifest, ok := manifest.(*ocischema.DeserializedManifest); ok && ocimanifest.Annotations != nil {
+			if created, ok := ocimanifest.Annotations["org.opencontainers.image.created"]; ok {
+				if t, err := time.Parse(time.RFC3339, created); err == nil {
+					createdDate = &t
+				}
+			}
+		}
+		imageType = "OCI"
+	} else if descriptor.MediaType == schema2.MediaTypeManifest {
+		imageType = "Docker V2"
+	}
+
+	if createdDate == nil {
+		if created, err := r.CreatedDate(ctx, repo, manifest.References()[0].Digest); err == nil {
+			createdDate = created
+		} else {
+			logrus.Errorf("getting created time from config layer for %s:%s failed: %v", repo, tag, err)
+			retErr = err
+			return
+		}
+	}
+	return
+}