[#228] client: Move isClientErrMaintenance from node

Signed-off-by: Ekaterina Lebedeva <ekaterina.lebedeva@yadro.com>

client/errors.go

@@ -67,6 +67,12 @@ func IsErrAPEManagerAccessDenied(err error) bool {
 	return wrapsErrType[*apistatus.APEManagerAccessDenied](err)
 }
 
+// IsErrNodeUnderMaintenance checks if err corresponds to FrostFS status return
+// corresponding to nodes being under maintenance. Supports wrapped errors.
+func IsErrNodeUnderMaintenance(err error) bool {
+	return wrapsErrType[*apistatus.NodeUnderMaintenance](err)
+}
+
 // returns error describing missing field with the given name.
 func newErrMissingResponseField(name string) error {
 	return fmt.Errorf("missing %s field in the response", name)

client/errors_test.go

@@ -38,6 +38,10 @@ func TestErrors(t *testing.T) {
 			check: client.IsErrSessionNotFound,
 			err:   new(apistatus.SessionTokenNotFound),
 		},
+		{
+			check: client.IsErrNodeUnderMaintenance,
+			err:   new(apistatus.NodeUnderMaintenance),
+		},
 	}
 
 	for i := range errs {