Rails 3.1.3 on Heroku: (No route matches [GET] “/assets/rails.png”)

Question

I\'ve installed a few basic apps on Heroku without problem, and this one (Rails 3.1.3) seemed fine in that it showed Rails welcome page

public/index.html.         


        

Answer 1

To get lazy initiation working with thin (on heroku) with rails 3.2.3 I had to do:

In config/application.rb:

if defined?(Bundler)
  # 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)
end

...


module Romulo
  class Application < Rails::Application

...

    # Enable the asset pipeline
    config.assets.enabled = true

    # Version of your assets, change this if you want to expire all your assets
    config.assets.version = '1.0'

    # get precompilation working on heroku:
    config.assets.initialize_on_precompile = true

    config.serve_static_assets = false
  end
end

In config/environments/production.rb:

# Compress JavaScripts and CSS
config.assets.compress = true

# Don't fallback to assets pipeline if a precompiled asset is missed
config.assets.compile = true

# Generate digests for assets URLs
config.assets.digest = true

No need to precompile assets.

Answer 2

It looks like you may not have precompiled your assets before you pushed to Heroku, try:

rake assets:precompile
git add .
etc etc

I think that should help. For more information, see here: http://devcenter.heroku.com/articles/rails31_heroku_cedar

Answer 3

No need to precompile and clutter your git!

heroku will precompile your assets

with rails 3.1.x you added this to application.rb

config.assets.initialize_on_precompile = false

UPDATE 16th july2012

also rails 3.2.x

it seems to be problem with ActiveRecord and database.yml ! If you don't use regular database, but use MongoDB, you will not need the above. However, if you do, you'll need to disable the initilize, as activerecord reads database tables when initializing, but database is not available at precompile phase at heroku.

with MongoDB it is not necessary.

/UPDATE

rails 3.2.x : Have a look at the top of application.rb. The OMA comments are mine, added for clarity

if defined?(Bundler)
  # If you precompile assets before deploying to production, use this line
  "OMA - comment this line"
  #Bundler.require(*Rails.groups(:assets => %w(development test)))
  # If you want your assets lazily compiled in production, use this line
  "OMA - uncomment this line"
  Bundler.require(:default, :assets, Rails.env)
end