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Do I need rails-ujs and jquery_ujs?

Nick McNeany asked in Javascript

I'm bulding a rails 5.1.x app so no jQuery, but I'm usining Bootstrap so I added it in.

I was adding in //= require jquery and //= require jquery_ujs, then noticed that rails 5.1 now ships with //= require rails-ujs. My initial reaction is rails-ujs replaces the need for jquery_ujs so I don't need it.

My question is, will I run into any problems with jQuery if I do not include //= require jquery_ujs ?

Thanks for the help!



I did an episode on the new Rails UJS library. It replaces everything jquery_ujs does, but it just doesn't require jQuery:

Feel free to add jquery in, but you won't need the jquery_ujs library. Everything will still function exactly the same as before, they just want to reduce dependencies.


My lazyness has been exposed! I didn't even bother to search the videos, haha!

Thanks for the help Chris! You're the man!


Hi, I am using the smart_listing gem and without requiring jquery_ujs I am getting some js errors. Probably smart_listing can be fixed. What i am trying to say is that there might be some compatibility issues with existing libraries.

P.S. so far I've removed rails_ujs and I'm only using jquery_ujs. So far no compat issues I see.

Update: actually if I enable both of them, then requests are processed twice instead of once. That means click form submit once but it is submitted twice. So one has to enable only one - rails-ujs or jquery_ujs.



@Alexander Kostadinov: yep, same result. you only need require rails_ujs, otherwise if you are doing any type of submission from client (for example), an alert will process twice.

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