can not update code

[zhzehong]

I add this code in my gulpfile.js, and when the js file changed, I can get the console output. But the code did not update in my server.
gulp.watch(['service/*.js'], function(file) {
console.log(file)
server.notify.apply(server, [file]);
});

I can reach http://localhost:35729/livereload.js.