rails 3.2.0 and heroku

Question

I have some troubles with rails 3.2.0 & ruby 1.9.3, I only created a new app with rails new command and I'm trying to deploy to heroku. I'm having the following app error:

An error occurred in the application and your page could not be served. Please try again in a few moments. If you are the application owner, check your logs for details.

After run heroku logs I get the following error:

Could not find activemodel-3.2.0 in any of the sources

Thanks in advance!!!!

GemFile

source 'https://rubygems.org'

gem 'rails', '3.2.0'

# Bundle edge Rails instead:
# gem 'rails', :git => 'git://github.com/rails/rails.git'

gem 'sqlite3'


# Gems used only for assets and not required
# in production environments by default.
group :assets do
  gem 'sass-rails',   '~> 3.2.3'
  gem 'coffee-rails', '~> 3.2.1'

  # See https://github.com/sstephenson/execjs#readme for more supported runtimes
  # gem 'therubyracer'

  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails'

# To use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.0.0'

# To use Jbuilder templates for JSON
# gem 'jbuilder'

# Use unicorn as the web server
# gem 'unicorn'

# Deploy with Capistrano
# gem 'capistrano'

# To use debugger
# gem 'ruby-debug19', :require => 'ruby-debug'

Gemfile.lock file

GEM
  remote: https://rubygems.org/
  specs:
    actionmailer (3.2.0)
      actionpack (= 3.2.0)
      mail (~> 2.4.0)
    actionpack (3.2.0)
      activemodel (= 3.2.0)
      activesupport (= 3.2.0)
      builder (~> 3.0.0)
      erubis (~> 2.7.0)
      journey (~> 1.0.0)
      rack (~> 1.4.0)
      rack-cache (~> 1.1)
      rack-test (~> 0.6.1)
      sprockets (~> 2.1.2)
    activemodel (3.2.0)
      activesupport (= 3.2.0)
      builder (~> 3.0.0)
    activerecord (3.2.0)
      activemodel (= 3.2.0)
      activesupport (= 3.2.0)
      arel (~> 3.0.0)
      tzinfo (~> 0.3.29)
    activeresource (3.2.0)
      activemodel (= 3.2.0)
      activesupport (= 3.2.0)
    activesupport (3.2.0)
      i18n (~> 0.6)
      multi_json (~> 1.0)
    arel (3.0.0)
    builder (3.0.0)
    coffee-rails (3.2.1)
      coffee-script (>= 2.2.0)
      railties (~> 3.2.0.beta)
    coffee-script (2.2.0)
      coffee-script-source
      execjs
    coffee-script-source (1.2.0)
    erubis (2.7.0)
    execjs (1.3.0)
      multi_json (~> 1.0)
    hike (1.2.1)
    i18n (0.6.0)
    journey (1.0.0)
    jquery-rails (2.0.0)
      railties (>= 3.2.0.beta, < 5.0)
      thor (~> 0.14)
    json (1.6.5)
    mail (2.4.1)
      i18n (>= 0.4.0)
      mime-types (~> 1.16)
      treetop (~> 1.4.8)
    mime-types (1.17.2)
    multi_json (1.0.4)
    polyglot (0.3.3)
    rack (1.4.0)
    rack-cache (1.1)
      rack (>= 0.4)
    rack-ssl (1.3.2)
      rack
    rack-test (0.6.1)
      rack (>= 1.0)
    rails (3.2.0)
      actionmailer (= 3.2.0)
      actionpack (= 3.2.0)
      activerecord (= 3.2.0)
      activeresource (= 3.2.0)
      activesupport (= 3.2.0)
      bundler (~> 1.0)
      railties (= 3.2.0)
    railties (3.2.0)
      actionpack (= 3.2.0)
      activesupport (= 3.2.0)
      rack-ssl (~> 1.3.2)
      rake (>= 0.8.7)
      rdoc (~> 3.4)
      thor (~> 0.14.6)
    rake (0.9.2.2)
    rdoc (3.12)
      json (~> 1.4)
    sass (3.1.12)
    sass-rails (3.2.3)
      railties (~> 3.2.0.beta)
      sass (>= 3.1.10)
      tilt (~> 1.3)
    sprockets (2.1.2)
      hike (~> 1.2)
      rack (~> 1.0)
      tilt (~> 1.1, != 1.3.0)
    sqlite3 (1.3.5)
    thor (0.14.6)
    tilt (1.3.3)
    treetop (1.4.10)
      polyglot
      polyglot (>= 0.3.1)
    tzinfo (0.3.31)
    uglifier (1.2.2)
      execjs (>= 0.3.0)
      multi_json (>= 1.0.2)

PLATFORMS
  ruby

DEPENDENCIES
  coffee-rails (~> 3.2.1)
  jquery-rails
  rails (= 3.2.0)
  sass-rails (~> 3.2.3)
  sqlite3
  uglifier (>= 1.0.3)

Answer 1

Rails 3.2 applications run fine on Cedar, I've just upgraded several applications to run on Cedar and are running on Heroku. Once you've updated your Gemfile and Gemfile.lock make sure you commit them both and push them both to Heroku. Heroku will then rebundle your application to use Rails 3.2.

Incidentally, I don't specify any version numbers on sass-rails or uglifier in my Gemfiles.

Of course, you can test in production mode running locally before you push to Heroku to see if it's going to work.