TLDR: Put all javascript library files under app/assets/libfolder. Refer the files without the libfolder

We always need to import some javascript libs to our Rails application. Some libs has correspondent gems. For example, jquery.js has a jquery-rails gem.

But some other libs may not have the correspondent gems. What’s more, it may be a waste to use a “wrapper gem” to just import a javascript file. Some wrapper gem may not up-to-date to the origin javascript lib. So we need to import javascript libs manually in some cases.

Rails default use sprockets to manage assets. And we always split assets into javascripts, stylesheets, images and fonts folders. But if we split a javascript library into these files, it maybe a little messy.

Actually we can put the files together in a same foler.

For example, I want to import bootstrap-sweetalert into my Rails app. I download the sweet-alert.less and sweet-alert.js. Then put the two files into vender/assets/sweet-alert. sweet-alert here is a new created folder.

The vender/assets/sweet-alert folder will be treat as base path to query assets. So we can refer the sweet-alert.js in our application.js as following:

 //= require sweet-alert

We can do the same for sweet-alert.less in our application.less.

Note that we have other ways to manage the assets. But it’s another topic then.