Heroku's rake task fails to precompile assets - NameError: uninitialized constant ValidatesTimeliness

Question

When I push my Rails 4 application to Heroku, it generates an "assets:precompile rake task" failure:

remote:   Running: rake assets:precompile
remote:   rake aborted!
remote:   NameError: uninitialized constant ValidatesTimeliness

It appears Heroku is unable to precompile the assets, because of an issue with the gem "ValidatesTimeliness." Based on Heroku's documentation on the Rails 4 asset pipeline, I ran

 RAILS_ENV=production bundle exec rake assets:precompile

to see if the problem also occurs in my local environment. It does; I got the same error locally.

Here's the contents of my config/intializers/validates_timeliness.rb file:

ValidatesTimeliness.setup do |config|
 # Extend ORM/ODMs for full support (:active_record, :mongoid).
 # config.extend_orms = [ :active_record ]
 #
 # Default timezone
 # config.default_timezone = :utc
 #
 # Set the dummy date part for a time type values.
 # config.dummy_date_for_time_type = [ 2000, 1, 1 ]
 #
 # Ignore errors when restriction options are evaluated
 # config.ignore_restriction_errors = false
 #
 # Re-display invalid values in date/time selects
 # config.enable_date_time_select_extension!
 #
 # Handle multiparameter date/time values strictly
 # config.enable_multiparameter_extension!
 #
 # Shorthand date and time symbols for restrictions
 # config.restriction_shorthand_symbols.update(
 #   :now   => lambda { Time.current },
 #   :today => lambda { Date.current }
 # )
 #
 # Use the plugin date/time parser which is stricter and extendable
 # config.use_plugin_parser = false
 #
 # Add one or more formats making them valid. e.g. add_formats(:date, 'd(st|rd|th) of mmm, yyyy')
 # config.parser.add_formats()
 #
 # Remove one or more formats making them invalid. e.g. remove_formats(:date, 'dd/mm/yyy')
 # config.parser.remove_formats()
 #
 # Change the amiguous year threshold when parsing a 2 digit year
 # config.parser.ambiguous_year_threshold =  30
 #
 # Treat ambiguous dates, such as 01/02/1950, as a Non-US date.
 # config.parser.remove_us_formats
end

Here's the contents of my gem file:

source 'https://rubygems.org'

gem 'rails', '4.1.8'
gem 'bootstrap-sass', '~> 3.2.0.0'
gem 'sass-rails', '~> 4.0.3'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.0.0'
gem 'jquery-rails'
gem 'turbolinks'
gem 'jbuilder', '~> 2.0'

group :doc do
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', require: false
end

group :development do
gem 'spring'
gem 'simple_form'
gem 'bcrypt', '~> 3.1.7'  
end

group :development, :test do
gem 'pg'
gem 'rspec-rails', '~> 3.1.0'
gem 'factory_girl_rails'
gem 'validates_timeliness', '~> 3.0'
gem 'validates_overlap'  
end

group :test do
gem 'byebug'
gem 'capybara', '~> 2.4.3'
gem 'shoulda-matchers', '~> 2.7.0'
gem 'faker'
gem 'paper_trail', '~> 3.0.6'
gem 'database_cleaner', '~> 1.3.0'
gem 'launchy', '~> 2.4.2'
gem 'rspec-activemodel-mocks'
gem 'selenium-webdriver', '~> 2.43.0'
end

group :production do
gem 'pg'
gem 'rails_12factor'

end

My hunch is I may need to do something in validates_timeliness set-up file, but I'm not sure what to do, because the rake failure relates to a "NameError." I'd appreciate any advice and guidance on how I should proceed.

Answer 1

In your Gemfile you've declared the validates_timeliness gem in a development group.

In Production it isn't installed, so you are getting an error. Try moving the validates_timeliness gem out of the group or, if you only need it in development, surround your initializer code with:

if Rails.env.development?
   ValidatesTimeliness.setup do |config|
   end
end