Turbolinks makes following links in your web application faster. Instead of letting the browser recompile the JavaScript and CSS between each page change, it keeps the current page instance alive and replaces only the body and the title in the head. Think CGI vs persistent process.
This is similar to pjax, but instead of worrying about what element on the page to replace, and tailoring the server-side response to fit, we replace the entire body. This means that you get the bulk of the speed benefits from pjax (no recompiling of the JavaScript or CSS) without having to tailor the server-side response. It just works.
Do note that this of course means that you'll have a long-running, persistent session with maintained state. That's what's making it so fast. But it also means that you may have to pay additional care not to leak memory or otherwise bloat that long-running state. That should rarely be a problem unless you're doing something really funky, but you do have to be aware of it. Your memory leaking sins will not be swept away automatically by the cleansing page change any more.
It depends. The more CSS and JavaScript you have, the bigger the benefit of not throwing away the browser instance and recompiling all of it for every page. Just like a CGI script that says "hello world" will be fast, but a CGI script loading Rails on every request will not.
In any case, the benefit ranges from twice as fast on apps with little JS/CSS, to three times as fast in apps with lots of it. Of course, your mileage may vary, be dependent on your browser version, the moon cycle, and all other factors affecting performance testing. But at least it's a yardstick.
The best way to find out just how fast it is? Try it on your own application. It hardly takes any effort at all.
Turbolinks is designed to be as light-weight as possible (so you won't think twice about using it even for mobile stuff). It does not require jQuery or any other framework to work. But it works great with jQuery or Prototype or whatever else have you.
Since pages will change without a full reload with Turbolinks, you can't by default rely on DOMContentLoaded to trigger your JavaScript code or jQuery.ready(). Instead, Turbolinks gives you a range of events to deal with the lifecycle of the page:
page:fetchstarting to fetch the target page (only called if loading fresh, not from cache).page:loadfetched page is being retrieved fresh from the server.page:restorefetched page is being retrieved from the 10-slot client-side cache.page:changepage has changed to the newly fetched version.
So if you wanted to have a client-side spinner, you could listen for page:fetch to start it and page:change to stop it. If you have DOM transformation that are not idempotent (the best way), you can hook them to happen only on page:load instead of page:change (as that would run them again on the cached pages).
By default, all internal HTML links will be funneled through Turbolinks, but you can opt out by marking links or their parent container with data-no-turbolink. For example, if you mark a div with data-no-turbolink, then all links inside of that div will be treated as regular links. If you mark the body, every link on that entire page will be treated as regular links.
Note that internal links to files not ending in .html, or having no extension, will automatically be opted out of Turbolinks. So links to /images/panda.gif will just work as expected.
Also, Turbolinks is installed as the last click handler for links. So if you install another handler that calls event.preventDefault(), Turbolinks will not run. This ensures that you can safely use Turbolinks with stuff like data-method, data-remote, or data-confirm from Rails.
Turbolinks will remember what assets were linked or referenced in the head of the initial page. If those assets change, either more or added or existing ones have a new URL, the page will do a full reload instead of going through Turbolinks. This ensures that all Turbolinks sessions will always be running off your latest JavaScript and CSS.
When this happens, you'll technically be requesting the same page twice. Once through Turbolinks to detect that the assets changed, and then again when we do a full redirect to that page.
A common case where this could happen is when a Javascript snippet (like the one from Google Analytics) adds a script tag to the head dynamically. Make sure to load Turbolinks before such snippets. Turbolinks will then only remember the assets which are present when it's loaded and ignore scripts which are added later.
Turbolinks will evaluate any script tags in pages it visit, if those tags do not have a type or if the type is text/javascript. All other script tags will be ignored.
You can use Turbolinks.visit(path) to go to a URL through Turbolinks.
Like pjax, this naturally only works with browsers capable of pushState. But of course we fall back gracefully to full page reloads for browsers that do not support it.
Turbolinks is designed to work with any browser that fully supports pushState and all the related APIs. This includes Safari 6.0+ (but not Safari 5.1.x!), IE10, and latest Chromes and Firefoxes.
Do note that existing JavaScript libraries may not all be compatible with Turbolinks out of the box due to the change in instantiation cycle. You might very well have to modify them to work with Turbolinks' new set of events.
- Add
gem 'turbolinks'to your Gemfile. - Run
bundle install. - Add
//= require turbolinksto your Javascript manifest file (usually found atapp/assets/javascripts/application.js). - Restart your server and you're now using turbolinks!
Thanks to Chris Wanstrath for his original work on Pjax. Thanks to Sam Stephenson and Josh Peek for their additional work on Pjax and Stacker and their help with getting Turbolinks released. Thanks to David Estes for handling the lion's share of post-release issues and feature requests. And thanks to everyone else who's fixed or reported an issue!