use zot as an extension name, ext as a component and search as a module

add endpoints field in ext discover api

distribution spec extension discover api has endpoints field required.

https://github.com/opencontainers/distribution-spec/blob/main/extensions/_oci.md#extensions-property-descriptions

Signed-off-by: Shivam Mishra <shimish2@cisco.com>

pkg/api/constants/extensions.go

@@ -5,5 +5,5 @@ const (
 	ExtCatalogPrefix     = "/_catalog"
 	ExtOciDiscoverPrefix = "/_oci/ext/discover"
 	// zot specific extensions.
-	ExtSearchPrefix = RoutePrefix + "/_search"
+	ExtSearchPrefix = RoutePrefix + "/_zot/ext/search"
 )

pkg/api/controller_test.go

@@ -4854,6 +4854,11 @@ func TestDistSpecExtensions(t *testing.T) {
 		err = json.Unmarshal(resp.Body(), &extensionList)
 		So(err, ShouldBeNil)
 		So(len(extensionList.Extensions), ShouldEqual, 1)
+		So(len(extensionList.Extensions[0].Endpoints), ShouldEqual, 1)
+		So(extensionList.Extensions[0].Name, ShouldEqual, "zot")
+		So(extensionList.Extensions[0].URL, ShouldContainSubstring, "_zot.md")
+		So(extensionList.Extensions[0].Description, ShouldNotBeEmpty)
+		So(extensionList.Extensions[0].Endpoints[0], ShouldEqual, constants.RoutePrefix+constants.ExtSearchPrefix)
 	})
 
 	Convey("start minimal zot server", t, func(c C) {