Use constant for global resources

builtin/providers/cloudstack/resource_cloudstack_template.go

@@ -219,12 +219,12 @@ func resourceCloudStackTemplateRead(d *schema.ResourceData, meta interface{}) er
 	d.Set("password_enabled", t.Passwordenabled)
 	d.Set("is_ready", t.Isready)
 
-	if t.Zoneid == "" {
-		d.Set("zone", "-1")
+	if t.Zoneid == IS_GLOBAL_RESOURCE {
+		setValueOrUUID(d, "zone", t.Zonename, IS_GLOBAL_RESOURCE)
 	} else {
 		setValueOrUUID(d, "zone", t.Zonename, t.Zoneid)
 	}
-	
+
 	setValueOrUUID(d, "os_type", t.Ostypename, t.Ostypeid)
 	
 	return nil

builtin/providers/cloudstack/resources.go

@@ -10,6 +10,8 @@ import (
 	"github.com/xanzy/go-cloudstack/cloudstack"
 )
 
+const IS_GLOBAL_RESOURCE = "-1"
+
 type retrieveError struct {
 	name  string
 	value string
@@ -53,7 +55,7 @@ func retrieveUUID(cs *cloudstack.CloudStackClient, name, value string) (uuid str
 	case "network":
 		uuid, err = cs.Network.GetNetworkID(value)
 	case "zone":
-		if value == "-1" {
+		if value == IS_GLOBAL_RESOURCE {
 			return value, nil
 		}
 		uuid, err = cs.Zone.GetZoneID(value)