package docker import ( "log" "github.com/hashicorp/packer/helper/multistep" ) func commHost(host string) func(multistep.StateBag) (string, error) { return func(state multistep.StateBag) (string, error) { if host != "" { log.Printf("Using host value: %s", host) return host, nil } containerId := state.Get("container_id").(string) driver := state.Get("driver").(Driver) return driver.IPAddress(containerId) } }