rails 3.1.0 ActionView::Template::Error (application.css isn't precompiled)

Question

By default Rails assumes that you have your files precompiled in the production environment, if you want use live compiling (compile your assets during runtime) in production you must set the config.assets.compile to true.

# config/environments/production.rb
...
config.assets.compile = true
...

You can use this option to fallback to Sprockets when you are using precompiled assets but there are any missing precompiled files.

If config.assets.compile option is set to false and there are missing precompiled files you will get an "AssetNoPrecompiledError" indicating the name of the missing file.

You will get better performance in production if you set config.assets.compile to false in production.rb and precompile your assets. You can precompile with this rake task:

bundle exec rake assets:precompile

If you are using Capistrano, version 2.8.0 has a recipe to handle this at deploy time. For more info, see the "In Production" section of the Asset Pipeline Guide: http://guides.rubyonrails.org/asset_pipeline.html

OK - I had the same problem. I didn't want to use "config.assets.compile = true" - I had to add all of my .css files to the list in config/environments/production.rb:

config.assets.precompile += %w( carts.css )

Then I had to create (and later delete) tmp/restart.txt

I consistently used the stylesheet_link_tag helper, so I found all the extra css files I needed to add with:

find . \( -type f -o -type l \) -exec grep stylesheet_link_tag {} /dev/null \;

A quick fix for capistrano user is to put this line to Capfile

# Uncomment if you are using Rails' asset pipeline
load 'deploy/assets'

For all those who are reading this but do not have problem with application.css and instead with their custom CSS classes e.g. admin.css, base.css etc.

Solution is to use as mentioned

bundle exec rake assets:precompile

And in stylesheets references just reference application.css

<%= stylesheet_link_tag    "application", :media => "all" %>

Since assets pipeline will precompile all of your stylesheets in application.css. This also happens in development so using any other references is wrong when using assets pipeline.

I was having the exact same error in my development environment. In the end all I needed to do in order to fix it was to add:

config.assets.manifest = Rails.root.join("public/assets")

to my config/environments/development.rb file and it fixed it. My final config in development related to assets looks like:

config.assets.compress = false  
config.assets.precompile += %w[bootstrap-alerts.js] #Lots of other space separated files
config.assets.compile = false
config.assets.digest = true
config.assets.manifest = Rails.root.join("public/assets")
config.assets.debug = true

I also had this issue, where trying to run in production without precompiling it would still throw not-precompiled errors. I had to change which line was commented application.rb:

  # If you precompile assets before deploying to production, use this line
  # Bundler.require(*Rails.groups(:assets => %w(development test)))
  # If you want your assets lazily compiled in production, use this line
  Bundler.require(:default, :assets, Rails.env)