add inspect of image

Author: CMGS

images/cloudimg/cloudimg.go

@@ -51,15 +51,23 @@ func (c *CloudImg) Pull(ctx context.Context, url string, tracker progress.Tracke
 	return pull(ctx, c.conf, c.store, url, tracker)
 }
 
+// Inspect returns the record for a single image. Returns (nil, nil) if not found.
+func (c *CloudImg) Inspect(ctx context.Context, id string) (result *types.Image, err error) {
+	err = c.store.With(ctx, func(idx *imageIndex) error {
+		refs := idx.LookupRefs(id)
+		if len(refs) == 0 {
+			return nil
+		}
+		result = images.EntryToImage(idx.Images[refs[0]], typ, c.imageSizer)
+		return nil
+	})
+	return
+}
+
 // List returns all locally stored cloud images.
 func (c *CloudImg) List(ctx context.Context) (result []*types.Image, err error) {
 	err = c.store.With(ctx, func(idx *imageIndex) error {
-		result = images.ListImages(idx.Images, typ, func(e *imageEntry) int64 {
-			if info, err := os.Stat(c.conf.CloudimgBlobPath(e.ContentSum.Hex())); err == nil {
-				return info.Size()
-			}
-			return 0
-		})
+		result = images.ListImages(idx.Images, typ, c.imageSizer)
 		return nil
 	})
 	return
@@ -106,3 +114,10 @@ func (c *CloudImg) Config(ctx context.Context, vms []*types.VMConfig) (result []
 	})
 	return
 }
+
+func (c *CloudImg) imageSizer(e *imageEntry) int64 {
+	if info, err := os.Stat(c.conf.CloudimgBlobPath(e.ContentSum.Hex())); err == nil {
+		return info.Size()
+	}
+	return 0
+}

images/images.go

@@ -12,6 +12,7 @@ type Images interface {
 	Type() string
 
 	Pull(context.Context, string, progress.Tracker) error
+	Inspect(context.Context, string) (*types.Image, error)
 	List(context.Context) ([]*types.Image, error)
 	Delete(context.Context, []string) ([]string, error)
 	RegisterGC(*gc.Orchestrator)

images/index.go

@@ -112,6 +112,22 @@ func DeleteByID[E any](ctx context.Context, logPrefix string, images map[string]
 	return deleted
 }
 
+// EntryToImage converts a single index entry to *types.Image.
+// Cheaper than ListImages for single-entry lookups — no map or slice allocation.
+func EntryToImage[E Entry](entry *E, typ string, sizer func(*E) int64) *types.Image {
+	if entry == nil {
+		return nil
+	}
+	e := *entry
+	return &types.Image{
+		ID:        e.EntryID(),
+		Name:      e.EntryRef(),
+		Type:      typ,
+		Size:      sizer(entry),
+		CreatedAt: e.EntryCreatedAt(),
+	}
+}
+
 // ListImages iterates the index and builds a list of types.Image.
 // sizer is provided by each backend to compute per-entry disk usage.
 func ListImages[E Entry](images map[string]*E, typ string, sizer func(*E) int64) []*types.Image {

images/oci/oci.go

@@ -54,28 +54,23 @@ func (o *OCI) Pull(ctx context.Context, image string, tracker progress.Tracker)
 	return pull(ctx, o.conf, o.store, image, tracker)
 }
 
+// Inspect returns the record for a single image. Returns (nil, nil) if not found.
+func (o *OCI) Inspect(ctx context.Context, id string) (result *types.Image, err error) {
+	err = o.store.With(ctx, func(idx *imageIndex) error {
+		refs := idx.LookupRefs(id)
+		if len(refs) == 0 {
+			return nil
+		}
+		result = images.EntryToImage(idx.Images[refs[0]], typ, o.imageSizer)
+		return nil
+	})
+	return
+}
+
 // List returns all locally stored images.
 func (o *OCI) List(ctx context.Context) (result []*types.Image, err error) {
 	err = o.store.With(ctx, func(idx *imageIndex) error {
-		result = images.ListImages(idx.Images, typ, func(e *imageEntry) int64 {
-			var total int64
-			for _, layer := range e.Layers {
-				if info, err := os.Stat(o.conf.BlobPath(layer.Digest.Hex())); err == nil {
-					total += info.Size()
-				}
-			}
-			if e.KernelLayer != "" {
-				if info, err := os.Stat(o.conf.KernelPath(e.KernelLayer.Hex())); err == nil {
-					total += info.Size()
-				}
-			}
-			if e.InitrdLayer != "" {
-				if info, err := os.Stat(o.conf.InitrdPath(e.InitrdLayer.Hex())); err == nil {
-					total += info.Size()
-				}
-			}
-			return total
-		})
+		result = images.ListImages(idx.Images, typ, o.imageSizer)
 		return nil
 	})
 	return
@@ -136,3 +131,23 @@ func (o *OCI) Config(ctx context.Context, vms []*types.VMConfig) (result [][]*ty
 	})
 	return
 }
+
+func (o *OCI) imageSizer(e *imageEntry) int64 {
+	var total int64
+	for _, layer := range e.Layers {
+		if info, err := os.Stat(o.conf.BlobPath(layer.Digest.Hex())); err == nil {
+			total += info.Size()
+		}
+	}
+	if e.KernelLayer != "" {
+		if info, err := os.Stat(o.conf.KernelPath(e.KernelLayer.Hex())); err == nil {
+			total += info.Size()
+		}
+	}
+	if e.InitrdLayer != "" {
+		if info, err := os.Stat(o.conf.InitrdPath(e.InitrdLayer.Hex())); err == nil {
+			total += info.Size()
+		}
+	}
+	return total
+}