Updating go implementation for zstd, removing the defer call, which c…

…auses invalid memory access when the writer closes. We already have calls to Close(), so we really don't need to defer this.

Updating oci_image_layer rule to define outputs inside the impl, so that it can choose the correct extension for the archive.

go/cmd/ocitool/createlayer_cmd.go

@@ -44,13 +44,11 @@ func CreateLayerCmd(c *cli.Context) error {
     if(config.UseZstd){
         zstdWriter = zstd.NewWriter(wc)
         mediaType = ocispec.MediaTypeImageLayerZstd
-        defer zstdWriter.Close()
         tw = tar.NewWriter(zstdWriter)
     } else {
         gzipWriter = gzip.NewWriter(wc)
         gzipWriter.Name = path.Base(out.Name())
         mediaType = ocispec.MediaTypeImageLayerGzip
-        defer gzipWriter.Close()
         tw = tar.NewWriter(gzipWriter)
     }
 

oci/image.bzl

@@ -26,11 +26,17 @@ def _oci_image_layer_impl(ctx):
 
     descriptor_file = ctx.actions.declare_file("{}.descriptor.json".format(ctx.label.name))
 
+    archive = None
+    if ctx.attr.zstd_compression:
+        archive = ctx.actions.declare_file(ctx.label.name + ".tar.zst")
+    else:
+        archive = ctx.actions.declare_file(ctx.label.name + ".tar.gz")
+
     ctx.actions.run(
         executable = toolchain.sdk.ocitool,
         arguments = [
                         "create-layer",
-                        "--out={}".format(ctx.outputs.layer.path),
+                        "--out={}".format(archive.path),
                         "--outd={}".format(descriptor_file.path),
                         "--dir={}".format(ctx.attr.directory),
                         "--bazel-label={}".format(ctx.label),
@@ -42,15 +48,16 @@ def _oci_image_layer_impl(ctx):
         inputs = ctx.files.files + ctx.files.file_map,
         outputs = [
             descriptor_file,
-            ctx.outputs.layer,
+            archive,
         ],
     )
 
     return [
         OCIDescriptor(
             descriptor_file = descriptor_file,
-            file = ctx.outputs.layer,
+            file = archive,
         ),
+        DefaultInfo(files = depset([archive])),
     ]
 
 oci_image_layer = rule(
@@ -77,9 +84,6 @@ oci_image_layer = rule(
         ),
     },
     toolchains = ["@com_github_datadog_rules_oci//oci:toolchain"],
-    outputs = {
-        "layer": "%{name}-layer.tar.gz",
-    },
 )
 
 def _oci_image_index_impl(ctx):