builder/amazon-instance: Omit access, secrety key if using IAM Instance Profile

builder/amazon/instance/builder.go

@@ -73,6 +73,15 @@ func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
 	}
 
 	if b.config.BundleUploadCommand == "" {
+		if b.config.IamInstanceProfile != "" {
+			b.config.BundleUploadCommand = "sudo -i -n ec2-upload-bundle " +
+				"-b {{.BucketName}} " +
+				"-m {{.ManifestPath}} " +
+				"-d {{.BundleDirectory}} " +
+				"--batch " +
+				"--region {{.Region}} " +
+				"--retry"
+		} else {
 			b.config.BundleUploadCommand = "sudo -i -n ec2-upload-bundle " +
 				"-b {{.BucketName}} " +
 				"-m {{.ManifestPath}} " +
@@ -83,6 +92,7 @@ func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
 				"--region {{.Region}} " +
 				"--retry"
 		}
+	}
 
 	if b.config.BundleVolCommand == "" {
 		b.config.BundleVolCommand = "sudo -i -n ec2-bundle-vol " +