Support multiple Regions (#171)

* Allow controller to run against regions in addition to us-west-2

* Use Region to build lattice endpoint

* Update it for endpoint environment

Author: liwenwu-amazon

pkg/aws/services/vpclattice.go

@@ -25,17 +25,14 @@ type defaultLattice struct {
 	vpclatticeiface.VpcLatticeAPI
 }
 
-const (
-	GammaEndpoint    = "https://mercury-gamma.us-west-2.amazonaws.com/"
-	BetaProdEndpoint = "https://vpc-lattice.us-west-2.amazonaws.com"
-)
-
 func NewDefaultLattice(sess *session.Session, region string) *defaultLattice {
 	var latticeSess vpclatticeiface.VpcLatticeAPI
+
+	latticeEndpoint := "https://vpc-lattice." + region + ".amazonaws.com"
 	endpoint := os.Getenv("LATTICE_ENDPOINT")
 
 	if endpoint == "" {
-		endpoint = BetaProdEndpoint
+		endpoint = latticeEndpoint
 	}
 
 	latticeSess = vpclattice.New(sess, aws.NewConfig().WithRegion(region).WithEndpoint(endpoint))