X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/865e5c1e3730117870eb1e485d553383626b882f..a6b9fb8166440eef3144150024a875c858db9bb6:/lib/controller/api/routable.go

diff --git a/lib/controller/api/routable.go b/lib/controller/api/routable.go
index 6049cba8e4..f887448829 100644
--- a/lib/controller/api/routable.go
+++ b/lib/controller/api/routable.go
@@ -15,3 +15,16 @@ import "context"
 // it to the router package would cause a circular dependency
 // router->arvadostest->ctrlctx->router.)
 type RoutableFunc func(ctx context.Context, opts interface{}) (interface{}, error)
+
+type RoutableFuncWrapper func(RoutableFunc) RoutableFunc
+
+// ComposeWrappers (w1, w2, w3, ...) returns a RoutableFuncWrapper that
+// composes w1, w2, w3, ... such that w1 is the outermost wrapper.
+func ComposeWrappers(wraps ...RoutableFuncWrapper) RoutableFuncWrapper {
+	return func(f RoutableFunc) RoutableFunc {
+		for i := len(wraps) - 1; i >= 0; i-- {
+			f = wraps[i](f)
+		}
+		return f
+	}
+}