I pin my assets in application.html.erb such:
<%= javascript_include_tag("scripts.js") %>
But when I look in later, it includes and scripts.js and application.js. Double time. How can I fix it and how can I put all my JS or CSS files into application.js(.css) without other files in <head> part?
Your scripts.js is required twice.
1 time from the require_tree . in your application.js
1 time from your javascript_include_tag("scripts.js")
Remove one of them and your scripts.js will be called once.
Moreover, if you want to load only one js file (application.js), just remove your javascript_include_tag and your compiled application.js will contain the javascript from scripts.js. (It's the same for CSS)
More documentation here
Related
I'm currently trying Rails 6.0.0.rc1 which seems to have moved the default javascript folder from app/assets/javascript to app/javascript. The application.js file is now located in app/javascript/packs. Now, I want to add a couple of js files, but for some reason they don't get imported and I can't find any documentation on how this can be done in Rails 6. I tried a couple of things:
Create a new folder custom_js under app/javascript/packs, putting all my js files there and then add a require "custom_js" to application.js.
Copy all my js files under app/javascript/channels (which should be included by default, since application.js has require("channels")).
Adding require_tree . to application.js, which was the previous approach.
How can I load my own js files inside a Rails 6 application?
Get better-organized code and avoid multiple javascript_pack_tags in your application.html.erb file with this approach:
Add your custom example.js javascript file to app/javascript/packs.
Add require("packs/example") to your application.js file.
I would have liked to add a comment to Asim Hashmi's correct answer. But I don't have enough reputation, so I'll add my suggestion as an answer instead.
It isn't necessary to include the ".js" extension inside of the require.
You need to do the following steps to add custom javascript file to rails 6 (webpacker)
1.Create your custom file named custom.js in app/javascript/packs directory.
For testing purpose, write any console.log in it.
// app/javascript/packs/custom.js
console.log("custom js file loaded")
2. Go to your application.html.erb and add the following line at the end of your <head></head>
<%= javascript_pack_tag 'custom', 'data-turbolinks-track': 'reload' %>
3. Now execute rake assets:precompile
This will pack your javascript code (including our custom file we just added)
Now reload your page and you should see the message
custom js file loaded
In your browser console.
My custom js has functions which will be called by embedded javascript of serveral html pages. Following snippet works in Rails6, compiled by webpacker:
put custom js file in folder app/javascript/packs e.g. app/javascript/packs/my_functions.js
say_hello = function(a_text){
console.log("HELLO "+ a_text);
}
add javascript_pack_tag in html file, e.g. index.html.erb .
<%= javascript_pack_tag 'my_functions' %>
<!-- html here -->
<script>
$(document).ready(function(){
say_hello('ABer')
});
</script>
Note : This line is inside html body, not in head
<script src="/packs/js/my_functions-1db66368ebbd2fe31abd.js"></script>
This is a question that several people have asked before, but none of the questions were quite asked or answered in a way that I found helpful, so I'm writing the question and answer that I would have found helpful.
I have a Rails 3.1+ app using the asset pipeline. There's one specific action that I want to have use different CSS. (In my specific case, I have a page that is intended to be printed, so it truly needs completely different CSS and does not need any Javascript.) Currently, I have only one application-specific CSS file. How do I add the new CSS file and direct the asset pipeline to use my file?
For example, right now, my app/assets looks like
app/assets
/javascript
application.js
custom.js.coffee
/css
application.css
custom.css.scss
I want to add a print.css file that is used by the view of a specific action. This view will not use the application.css file. How do I add print.css?
I found this blog post to be very helpful: http://blog.seancarpenter.net/2012/11/05/page-specific-javascript-with-the-asset-pipeline/. My answer paraphrases what this blogger already wrote and fills in a few missing details.
First, it's important that you've read and understood the Rails Guide to the Asset Pipeline. Unfortunately, this guide doesn't clearly explain how to add action-specific assets, but it does cover some concepts you need to know. Made sure you understand these ideas:
That the asset pipeline compiles Javascript, CSS, and other assets so that Rails servers can cache assets for better performance.
That manifest files use commands like require, require_tree, and require_self to indicate which files are compiled together.
That in order for the asset pipeline to work properly in production, you need to manually run rake assets:precompile to produce the compiled, minified assets in the public directory.
These ideas are the minimum "need-to-know" pieces of information about the asset pipeline. If you don't already understand these ideas, you don't have an "expert or enthusiast" level of knowledge about the pipeline, and unfortunately, SO isn't the right place to learn this stuff. Fortunately, the the Rails Guide to the Asset Pipeline is a short 15-minute read and can get you up to speed quickly if you need it.
Second, these are the changes you need to make in order to ensure that the asset pipeline correctly sees and handles your new print.css file.
Follow these steps:
Add your print.css file to app/assets/css.
You'll need to create a manifest file that will show Rails where to find print.css. You need to do this, even though you only have a single CSS file you're adding. This is an easy step:
Add a file called print.js to app/assets/javascript.
Add this line to print.js:
//= require print
This will be the only line in the entire print.js file. If I understand correctly, Rails expects manifest files to have the file extension .js, which is why we aren't using print.css as the manifest file.
We now need to instruct Rails to find and use the print.js manifest. Add the following line in your config/application.rb file:
config.assets.precompile += %w( print.js )
We're almost finished! However, the already-present application.js manifest includes the line //= require_tree . which means that it will include your print.css file. This will cause your print.css styling to affect your entire site, not just the single view. There are two ways of dealing with this:
If application.js and print.js do not share any assets, you can use the stub command in your application.js to exclude the assets used in print.js. What this does is instruct application.js to remove any of the assets that print.js references from its own list of referenced files. Our modified application.js looks like:
(snip...)
require_tree .
stub print
See this answer for more information.
If your print.js and application.js files share some assets, you'll need to move all of the assets used by application.js into subdirectories. I didn't do this myself, so I'm not the most help in this area. Look at this answer for instructions.
Now we have included print.css in the asset pipeline. We now need to direct Rails to use print.css in your specific view.
Let's say your action is in the reports controller, and that the action is named print_reports. This means we have a reports_controller.rb file and a print_reports.html.erb (or .haml) file. We need to make several changes to these files.
To start, add a new layout in app/views/layouts. Perhaps call it print.html.erb. We'll use this new layout for your print_reports.html.erb file. Set it up as you desire. For a page intended to be printed, this will likely be very simple, such as
<html>
<head>
<title="Print">
</head>
<body>
<%= yield %>
</body>
</html>
Using a separate layout the disadvantage that it's difficult to keep this layout and the layout used by the rest of the application in sync, but if you are using separate CSS files for the action, it's unlikely that you want the layout to be the same anyway.
Add a stylesheet_link_tag in the layout's header pointing to your print.css:
<html>
<head>
<title="Print"/>
<%= stylesheet_link_tag "print" %>
</head>
<body>
<%= yield %>
</body>
</html>
In the controller, we'll tell Rails to use our new layout for the action. Add the line layout 'print', only: [:print_reports] to your controller:
class reports_controller < ApplicationController
layout 'print', only: [:print_reports]
#snip
See this question for more information and a few different approaches.
At this point, when you run the app, your print_reports action should be using print.css correctly!
Remember to run rake assets:precompile before deploying on the server.
Official Solution
It is documented in the official Rails Guides here: http://guides.rubyonrails.org/asset_pipeline.html#controller-specific-assets
Actually you can leave out the require_tree directive (located in application.css and application.js) then use this in your template:
For controller specific JavaScript:
<%= javascript_include_tag params[:controller] %>
For controller specific CSS:
<%= stylesheet_link_tag params[:controller] %>
All of you are putting very complicated answers.
1 Go to app/assets/stylesheets
2.Make a file with the extension .css
3.Go to config/initializers/assets.rb
4.Put this line of of code Rails.application.config.assets.precompile += %w( file.css )
5.Replace file.css with the file you created
6.Go to your html.erb file
7.Type this in the <head>, <%= stylesheet_link_tag "file" %>
8.Replace file with the filename(no extension in the name)
Good Job you linked the file!
There's one specific action that I want to have use different CSS.
Here's an alternative way to accomplish what you're looking for:
Add the controller name and action name to the app body in your /views/layouts/application.html.rb:
<body class="<%= controller_name %>-<%= action_name %>">
<%= yield %>
</body>
Then in your .scss file:
.controller_name-action_name {
// your css goes here
}
So if your controller was static_pages and your action was home:
.static_pages-home {
// your css goes here
}
Tada! Your css only appears for that specific action.
In your layout
<head>
// ...
<%= yield :stylesheets %>
</head>
In your view
<%= provide :stylesheets do %>
// your page-specific css
<% end %>
I am reading rails guides documentation for asset pipeline.
It states that coffeescript page specific generated files
are by default ready to user if there is a require_tree directive on the manifest.
This is not working with me I have to do include this
<%= javascript_include_tag params[:controller] %>
on the specific controller.
What am I missing ?
The asset pipeline will compress all of your JS into a single file, application.js. In order to call JS for a specific page, you will need to organize your JS by controller and action. There is a gem, RailsScript that does this automatically and it's compatible with Turbolinks which can give you a single page application feel.
RailsScript only takes a few minutes to learn, https://github.com/gemgento/rails_script.
A specific example using rails script:
# app/assets/javascripts/users.js.coffee
window.App ||= {}
class App.Users extends App.Base
show: ->
alert('The users#show action!')
I think you are misunderstanding the asset-pipeline in general. It doesn't load the javascript-files individually, but rather all the .js.coffee files will get compiled into one big js-file, which you have to include in your views/layout like this
<%= stylesheet_link_tag "application", media: "all", "data-turbolinks-track" => true %>
If you want some js-code that is only available in one view, you definitely should not include that into the asset-pipeline.
Not sure if I've misunderstood your first paragraph, but I think what the line means is that if your application.js manifest contains a line like:
//= require_tree .
Then yes indeed, page specific javascript, or coffeescript will be loaded, not only for that specific page, for for all pages. If you want to constrain assets to certain pages like you've described, you will need a file located in app/assets/javascripts/ with the pluralized name of the controller, and .js.
I would personally create this as another manifest for that specific page, that way I can load multiple assets. Lets say you have a controller called UsersController, with various assets used by that controller's views. What you then need, in order for the line you wrote in your question to work, is a .js filed users.js or users.js.coffee in the app/assets/javascript directory.
Alternatively, to maintain the naming convention, I do something like this:
<%= javascript_include_tag "application-#{params[:controller]}"%>
and then of course name my file appropriate (application-users.js).
Also, when you do this, you'll want to stop your page-specific assets from loading for all controllers. Simply remove the //= require_tree . line and replace it with explicit //= require lines as needed.
Here's a way to do page-specific javascript in rails.
Install the jquery-readyselector.js plugin. (It's 18 lines)
a. Copy the contents of https://raw.github.com/Verba/jquery-readyselector/master/jquery.readyselector.js
b. Paste the contents to a new file at assets/javascripts/jquery_readyselector.js
c. Require jquery-readyselector
// assets/javascripts/application.js
//= require jquery_readyselector
//= require_tree .
Create CSS classes so we have a way to reference each page individually.
<%# views/layouts/application.html.erb %>
<body class="<%= controller_name %> <%= action_name %>">
Now we can scope our javascript to our page using CSS.
// assets/javascripts/posts.js
$(".posts.index").ready(function() {
});
I have multiple files in my app/assets/javscripts folder, application.js.erb, page.js.erb, sections.js.erb & scraped.js.erb.
Rails loads them all in my layout with <%= javascript_include_tag "application" %> in application.html.erb layout. Which is called from the PagesController.
I do not want scraped.js.erb to be loaded at all & sections.js.erb I would like to only be loaded from the SectionsController.
From my understanding (after reading http://guides.rubyonrails.org/asset_pipeline.html) that's how the asset pipeline worked. That if called from the PagesController it would load application.js.erb & page.js.erb but obviously that's not the case.
Am I doing something wrong? Could someone explain to me how the asset pipeline works? And how I can only use select assets rather than all of them?
Check your manifest file, in assets/javascript you got the file application.js, it contains
//= require_tree . which include during compilation all files of the directory tree.
If you want to exclude some files you can either require your files one by one: // require my_file, either create sub directories in your javascript directory and use
//= require_directory my_directory
Read more http://guides.rubyonrails.org/asset_pipeline.html
I'm a little confused by when I need to add an asset to config.assets.precompile and when it's not necessary.
(It's possible that my problem may stem from the fact that this app was migrated from rails 2.x; at some point soon I'm going to rebuild it from the ground up as a 3.x app, but don't have the time for that yet.)
Here's my issue: I have a .css and .js files that are not being found by sprockets unless I add them to config.assets.precompile in application.rb. I can't imagine I have to do this for every .js and .css, do I?
For example, one file I'm having this issue with is app/assets/stylesheets/facybox.css.
application.css is:
/*
*= require_self
*= require_directory .
*/
(yes, require_directory instead of require_tree intentionally).
I run rake assets:precompile on my server during deploy. The resulting application.css has the contents of facybox.css in it.
facybox.css is referred to in a partial, like this:
<% content_for :header do %>
<%= stylesheet_link_tag "facybox" %>
<% end %>
But when I go to a page that includes the partial, I get:
Sprockets::Helpers::RailsHelper::AssetPaths::AssetNotPrecompiledError in Admin#compositions
Showing /srv/zmx/releases/5420c4dde6fbec53d78cffe78396085f263ed039/app/views/shared/_preview_assets.erb where line #6 raised:
facybox.css isn't precompiled
which I assume is because sprockets is looking for the fingerprinted copy of the file, which doesn't exist unless I add it to config.assets.precompile. Then all is hunky-dory.
Can someone explain?
The rules for precompiling are simple:
If an asset is required in one of the application manifests you do not need to add it to precompile.
If an asset needs to be referenced directly in a Rails view then you DO need to add it (and you should remove it from any manifests).
As you said yourself, the contents of facybox.css are already included in your application.css.
This means that you can just remove the stylesheet_link_tag from your partial and also any other places where you use facybox.css. You would have to do the same for all other stylesheets that you already have included in your application.css