refactor runtime version election

srl-labs · Jun 16, 2021 · 91bcd27 · 91bcd27
1 parent 793cb48
commit 91bcd27
Showing 1 changed file with 10 additions and 5 deletions.
diff --git a/clab/clab.go b/clab/clab.go
@@ -59,12 +59,17 @@ func WithTimeout(dur time.Duration) ClabOption {
 
 func WithRuntime(name string, d bool, dur time.Duration, gracefulShutdown bool) ClabOption {
 	return func(c *CLab) {
-		if name == "" {
-			name = os.Getenv("CLAB_RUNTIME")
-			if name == "" {
-				name = runtime.DockerRuntime
-			}
+		// define runtime name.
+		// order of preference: cli flag -> env var -> default value of docker
+		envN := os.Getenv("CLAB_RUNTIME")
+		switch {
+		case name != "":
+		case envN != "":
+			name = envN
+		default:
+			name = runtime.DockerRuntime
 		}
+
 		if rInit, ok := runtime.ContainerRuntimes[name]; ok {
 			c.Runtime = rInit()
 			err := c.Runtime.Init(