Heroku deprecation warnings when trying to migrate the database - heroku

Question

I have a Rails 3.2 app that I've created and want to deploy it on Heroku.
I created a new session on the cedar stack and pushed up my app to it.
However, when I try to migrate the DB I get deprecation warnings.
I ran the migrate commend with the --trace command and here's what it gave me:
** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
rake aborted!
uninitialized constant SimpleForm
/app/config/initializers/simple_form.rb:2:in `<top (required)>'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/engine.rb:588:in `block (2 levels) in <class:Engine>'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/engine.rb:587:in `each'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/engine.rb:587:in `block in <class:Engine>'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/initializable.rb:30:in `instance_exec'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/initializable.rb:30:in `run'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/initializable.rb:55:in `block in run_initializers'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/initializable.rb:54:in `each'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/initializable.rb:54:in `run_initializers'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/application.rb:136:in `initialize!'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/railtie/configurable.rb:30:in `method_missing'
/app/config/environment.rb:5:in `<top (required)>'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/application.rb:103:in `require'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/application.rb:103:in `require_environment!'
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.2/lib/rails/application.rb:292:in `block (2 levels) in initialize_tasks'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `call'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `block in execute'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `each'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `execute'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:158:in `block in invoke_with_call_chain'
/usr/local/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:176:in `block in invoke_prerequisites'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:174:in `each'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:174:in `invoke_prerequisites'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:157:in `block in invoke_with_call_chain'
/usr/local/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:144:in `invoke'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:116:in `invoke_task'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block (2 levels) in top_level'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `each'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block in top_level'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:88:in `top_level'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:66:in `block in run'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run'
/app/vendor/bundle/ruby/1.9.1/gems/rake-0.9.2.2/bin/rake:33:in `<top (required)>'
/app/vendor/bundle/ruby/1.9.1/bin/rake:19:in `load'
/app/vendor/bundle/ruby/1.9.1/bin/rake:19:in `<main>'
Tasks: TOP => db:migrate => environment
My app works fine locally.
Here's my gem file:
source 'https://rubygems.org'
gem 'rails', '3.2.2'
# Bundle edge Rails instead:
# gem 'rails', :git => 'git://github.com/rails/rails.git'
group :production do
gem 'thin'
gem 'pg'
end
group :development, :test do
gem 'sqlite3'
end
# 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', '~> 0.9.2'
gem 'bootstrap-sass'
gem 'uglifier', '>= 1.0.3'
gem 'twitter-bootstrap-rails', '2.0.2'
gem 'simple_form'
gem 'fog'
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 app server
# gem 'unicorn'
# Deploy with Capistrano
# gem 'capistrano'
# To use debugger
# gem 'ruby-debug19', :require => 'ruby-debug'

Answer 1

move the simple_form gem outside your :assets group - mine is under the jquery-rails gem reference then make sure you run this command locally in your console before pushing to heroku:
RAILS_ENV=production bundle exec rake assets:precompile
hope that helps!