Rails Concerns and Turbolinks

Rails Concerns and Turbolinks

Presented by

Zahidul Hasan

What is Concerns?

• Concerns provides a way that allow us to keep our code organizedand DRY

• Basically, the idea is to extract common and/or context specific chunks of code in order to clean up the models/controllers and avoid them from getting too fat and messy

More Information

• Concerns are supported by Rails 3 but have become more official in Rails 4

• Those who have worked with a Rails 4 app, might have probably noticed the app/models/concerns and app/controllers/concernsdirectories

Why should we use concerns?

• DRYing up model codes

• Skin-nizing Fat Models

DRYing up model codes

Create a commentable.rb file in app/model/concerns

Skin-nizing Fat Models

• Create a attendable.rb file in app/model/concern/event folder

• Create a commentable.rb file in app/model/concern/event folder

Controller Concerns

• Controllers can also have concerns

• Purpose will be the same: DRYing

Turbolinks

• Feature of rails 4

• Prevents the browser from reloading the JavaScript and CSS between each page change

• Its almost similar to PJAX

JavaScript pushState

• Javascript API for HTML5: History Interface

• pushState can be used to store the navigation history

PJAX

• PJAX is a combination of the terms pushState and AJAX

• Instead of reloading the whole page when clicking a link, just load the part of the page that needs updating

• On the client-side we have to define the container that should be replaced when a link is clicked

Turbolinks

• Instead of replacing only parts a page it loads a complete website from the server and replaces the <title> and <body> in the currently loaded DOM

• Unlike PJAX we don't have to mark links and containers, Turbolinkswill handle that for us

Comparison between Turbolinks and PJAX

• Turbolinks definitely improve client-side page loading, but the server still has to render the complete website

• PJAX renders only those parts of a website that really need to be updated, need additional work when developing the application

• Turbolinks will improve page load significantly if the pages share JavaScript and CSS styling. PJAX comes in handy, when server-side performance is an issue

Thank You

Rails Concerns and Turbolinks

Technology