deprecate estargz

README.md

@@ -36,7 +36,7 @@ Over time, we will add new functionality under experimental environment variable
 
 | Env Var | Value(s) | What is does |
 |---------|----------|--------------|
-| `GGCR_EXPERIMENT_ESTARGZ` | `"1"` | When enabled this experiment will direct `tarball.LayerFromOpener` to emit [estargz](https://github.com/opencontainers/image-spec/issues/815) compatible layers, which enable them to be lazily loaded by an appropriately configured containerd. |
+| `GGCR_EXPERIMENT_ESTARGZ` | `"1"` | ⚠️DEPRECATED⚠️: When enabled this experiment will direct `tarball.LayerFromOpener` to emit [estargz](https://github.com/opencontainers/image-spec/issues/815) compatible layers, which enable them to be lazily loaded by an appropriately configured containerd. |
 
 
 ### `v1.Image`

pkg/v1/tarball/layer.go

@@ -160,13 +160,17 @@ func WithCompressedCaching(l *layer) {
 // WithEstargzOptions is a functional option that allow the caller to pass
 // through estargz.Options to the underlying compression layer.  This is
 // only meaningful when estargz is enabled.
+//
+// Deprecated: WithEstargz is deprecated, and will be removed in a future release.
 func WithEstargzOptions(opts ...estargz.Option) LayerOption {
 	return func(l *layer) {
 		l.estgzopts = opts
 	}
 }
 
 // WithEstargz is a functional option that explicitly enables estargz support.
+//
+// Deprecated: WithEstargz is deprecated, and will be removed in a future release.
 func WithEstargz(l *layer) {
 	oguncompressed := l.uncompressedopener
 	estargz := func() (io.ReadCloser, error) {
@@ -238,6 +242,7 @@ func LayerFromOpener(opener Opener, opts ...LayerOption) (v1.Layer, error) {
 	}
 
 	if estgz := os.Getenv("GGCR_EXPERIMENT_ESTARGZ"); estgz == "1" {
+		logs.Warn.Println("GGCR_EXPERIMENT_ESTARGZ is deprecated, and will be removed in a future release.")
 		opts = append([]LayerOption{WithEstargz}, opts...)
 	}