fix: set created property for scratch base

Author: thesayyn

examples/assert.bzl

@@ -30,7 +30,8 @@ def assert_oci_config(
         architecture_eq = None,
         os_eq = None,
         variant_eq = None,
-        labels_eq = None):
+        labels_eq = None,
+        created_eq = None):
     "assert that an oci_image has specified config metadata according to https://github.com/opencontainers/image-spec/blob/main/config.md"
     pick = []
 
@@ -66,6 +67,9 @@ def assert_oci_config(
     if variant_eq:
         config_json["variant"] = variant_eq
 
+    if created_eq:
+        config_json["created"] = created_eq
+
     pick += ["." + k for k in config_json.keys()]
 
     if len(config.keys()):

examples/assertion/BUILD.bazel

@@ -385,6 +385,19 @@ sh_test(
     data = [":case12"],
 )
 
+# Case 14: created property should be epoch start
+oci_image(
+    name = "case14",
+    architecture = "arm64",
+    os = "linux",
+)
+
+assert_oci_config(
+    name = "test_case14",
+    created_eq = "1970-01-01T00:00:00Z",
+    image = ":case14",
+)
+
 # build them as test.
 build_test(
     name = "test",

oci/private/image.sh

@@ -27,7 +27,7 @@ function base_from_scratch() {
     layers: []
   }' | update_manifest
   # Create the image config when there is annotations
-  jq -n --argjson platform "$platform" '{config:{}, rootfs:{type: "layers", diff_ids:[]}} + $platform' | update_config >/dev/null
+  jq -n --argjson platform "$platform" '{created: "1970-01-01T00:00:00Z", config:{}, rootfs:{type: "layers", diff_ids:[]}} + $platform' | update_config >/dev/null
 }
 
 function base_from() {