Q:

Nokogiri and Openshift

I uploaded my Rails app in Openshift server and I obtained the following error:

I searched in Google but I didn't find solutions.
I have Ruby 2.0 and Rails 4.
On my local host my application works without problem but when I upload it it doesn't work because of this error.
I'm on Windows 8.
Here is my Gemfile and Gemfile.lock:
source 'https://rubygems.org'

gem 'rails', '4.2.4'
gem 'sqlite3'
gem 'sass-rails', '~> 5.0'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.1.0'
gem 'jquery-rails'
gem 'turbolinks'
gem 'jbuilder', '~> 2.0'
gem 'sdoc', '~> 0.4.0', group: :doc

group :development, :test do
gem 'byebug'
end

group :development do
gem 'web-console', '~> 2.0'
end

gem 'tzinfo-data', platforms: [:mingw, :mswin, :jruby]
gem 'rake'
gem 'rack'
gem 'nokogiri'

Gemfile.lock
GEM
  remote: https://rubygems.org/
  specs:
    actionmailer (4.2.4)
      actionpack (= 4.2.4)
      actionview (= 4.2.4)
      activejob (= 4.2.4)
      mail (~> 2.5, >= 2.5.4)
      rails-dom-testing (~> 1.0, >= 1.0.5)
    actionpack (4.2.4)
      actionview (= 4.2.4)
      activesupport (= 4.2.4)
      rack (~> 1.6)
      rack-test (~> 0.6.2)
      rails-dom-testing (~> 1.0, >= 1.0.5)
      rails-html-sanitizer (~> 1.0, >= 1.0.2)
    actionview (4.2.4)
      activesupport (= 4.2.4)
      builder (~> 3.1)
      erubis (~> 2.7.0)
      rails-dom-testing (~> 1.0, >= 1.0.5)
      rails-html-sanitizer (~> 1.0, >= 1.0.2)
    activejob (4.2.4)
      activesupport (= 4.2.4)
      globalid (>= 0.3.0)
    activemodel (4.2.4)
      activesupport (= 4.2.4)
      builder (~> 3.1)
    activerecord (4.2.4)
      activemodel (= 4.2.4)
      activesupport (= 4.2.4)
      arel (~> 6.0)
    activesupport (4.2.4)
      i18n (~> 0.7)
      json (~> 1.7, >= 1.7.7)
      minitest (~> 5.1)
      thread_safe (~> 0.3, >= 0.3.4)
      tzinfo (~> 1.1)
    arel (6.0.3)
    binding_of_caller (0.7.2)
      debug_inspector (>= 0.0.1)
    builder (3.2.2)
    byebug (8.2.2)
    coffee-rails (4.1.1)
      coffee-script (>= 2.2.0)
      railties (>= 4.0.0, < 5.1.x)
    coffee-script (2.4.1)
      coffee-script-source
      execjs
    coffee-script-source (1.10.0)
    concurrent-ruby (1.0.1)
    debug_inspector (0.0.2)
    erubis (2.7.0)
    execjs (2.6.0)
    globalid (0.3.6)
      activesupport (>= 4.1.0)
    i18n (0.7.0)
    jbuilder (2.4.1)
      activesupport (>= 3.0.0, < 5.1)
      multi_json (~> 1.2)
    jquery-rails (4.1.1)
      rails-dom-testing (>= 1, < 3)
      railties (>= 4.2.0)
      thor (>= 0.14, < 2.0)
    json (1.8.3)
    loofah (2.0.3)
    mail (2.6.3)
      mime-types (>= 1.16, < 3)
    mime-types (2.99.1)
    mini_portile2 (2.0.0)
    minitest (5.8.4)
    multi_json (1.11.2)
      mini_portile2 (~> 2.0.0.rc2)
    nokogiri (1.6.7.2-x86-mingw32)
      mini_portile2 (~> 2.0.0.rc2)
    rack (1.6.4)
    rack-test (0.6.3)
      rack (>= 1.0)
    rails (4.2.4)
      actionmailer (= 4.2.4)
      actionpack (= 4.2.4)
      actionview (= 4.2.4)
      activejob (= 4.2.4)
      activemodel (= 4.2.4)
      activerecord (= 4.2.4)
      activesupport (= 4.2.4)
      bundler (>= 1.3.0, < 2.0)
      railties (= 4.2.4)
      sprockets-rails
    rails-deprecated_sanitizer (1.0.3)
      activesupport (>= 4.2.0.alpha)
    rails-dom-testing (1.0.7)
      activesupport (>= 4.2.0.beta, < 5.0)
      rails-deprecated_sanitizer (>= 1.0.1)
    rails-html-sanitizer (1.0.3)
      loofah (~> 2.0)
    railties (4.2.4)
      actionpack (= 4.2.4)
      activesupport (= 4.2.4)
      rake (>= 0.8.7)
      thor (>= 0.18.1, < 2.0)
    rake (11.1.0)
    rdoc (4.2.2)
      json (~> 1.4)
    sass (3.4.21)
    sass-rails (5.0.4)
      railties (>= 4.0.0, < 5.0)
      sass (~> 3.1)
      sprockets (>= 2.8, < 4.0)
      sprockets-rails (>= 2.0, < 4.0)
      tilt (>= 1.1, < 3)
    sdoc (0.4.1)
      json (~> 1.7, >= 1.7.7)
      rdoc (~> 4.0)
    sprockets (3.5.2)
      concurrent-ruby (~> 1.0)
      rack (> 1, < 3)
    sprockets-rails (3.0.4)
      actionpack (>= 4.0)
      activesupport (>= 4.0)
      sprockets (>= 3.0.0)
    sqlite3 (1.3.11-x86-mingw32)
    thor (0.19.1)
    thread_safe (0.3.5)
    tilt (2.0.2)
    turbolinks (2.5.3)
      coffee-rails
    tzinfo (1.2.2)
      thread_safe (~> 0.1)
    tzinfo-data (1.2016.1)
      tzinfo (>= 1.0.0)
    uglifier (2.7.2)
      execjs (>= 0.3.0)
      json (>= 1.8.0)
    web-console (2.3.0)
      activemodel (>= 4.0)
      binding_of_caller (>= 0.7.2)
      railties (>= 4.0)
      sprockets-rails (>= 2.0, < 4.0)

PLATFORMS
  x86-mingw32

DEPENDENCIES
  byebug
  coffee-rails (~> 4.1.0)
  jbuilder (~> 2.0)
  jquery-rails
  nokogiri
  rack
  rails (= 4.2.4)
  rake
  sass-rails (~> 5.0)
  sdoc (~> 0.4.0)
  sqlite3
  turbolinks
  tzinfo-data
  uglifier (>= 1.3.0)
  web-console (~> 2.0)

BUNDLED WITH
   1.10.4

Edit:
C:\Bitnami\game_test>bundle install
Using rake 11.1.0
Using i18n 0.7.0
Using json 1.8.3
Using minitest 5.8.4
Using thread_safe 0.3.5
Using tzinfo 1.2.2
Using activesupport 4.2.4
Using builder 3.2.2
Using erubis 2.7.0
Using mini_portile2 2.0.0
Using nokogiri 1.6.7.2
Using rails-deprecated_sanitizer 1.0.3
Using rails-dom-testing 1.0.7
Using loofah 2.0.3
Using rails-html-sanitizer 1.0.3
Using actionview 4.2.4
Using rack 1.6.4
Using rack-test 0.6.3
Using actionpack 4.2.4
Using globalid 0.3.6
Using activejob 4.2.4
Using mime-types 2.99.1
Using mail 2.6.3
Using actionmailer 4.2.4
Using activemodel 4.2.4
Using arel 6.0.3
Using activerecord 4.2.4
Using debug_inspector 0.0.2
Using binding_of_caller 0.7.2
Using byebug 8.2.2
Using coffee-script-source 1.10.0
Using execjs 2.6.0
Using coffee-script 2.4.1
Using thor 0.19.1
Using railties 4.2.4
Using coffee-rails 4.1.1
Using concurrent-ruby 1.0.1
Using multi_json 1.11.2
Using jbuilder 2.4.1
Using jquery-rails 4.1.1
Using bundler 1.10.4
Using sprockets 3.5.2
Using sprockets-rails 3.0.4
Using rails 4.2.4
Using rdoc 4.2.2
Using sass 3.4.21
Using tilt 2.0.2
Using sass-rails 5.0.4
Using sdoc 0.4.1
Using sqlite3 1.3.11
Using turbolinks 2.5.3
Using tzinfo-data 1.2016.1
Using uglifier 2.7.2
Using web-console 2.3.0
Updating files in vendor/cache
Bundle complete! 15 Gemfile dependencies, 54 gems now installed.
Use `bundle show [gemname]` to see where a bundled gem is installed.

A:

Last night, João Gonçalves gave me useful advice.
The problem was on the Openshift server-side because the server wasn't able to load the nokogiri gem.
Here the things I did:

Download Putty for SSH, because I needed to connect to my Openshift server.
You need to download putty.exe and puttygen.exe. I'm on Windows, so if you have another OS you have to find another way to connect through SSH to your server.
Follow this guide to configure Putty.
When you have to enter the hostname or IP in Putty for the is prompt: 
Hostname(or IP address)

you have to take your Remote Access (the string under Remote Access without the SSH prefix), as you can see in the picture, and paste it into Putty.

Connect to your server and change to the directory of your application.  I saw where my directory was using rhc tail appname. As you can see in the first picture of this post you can see the following path:
openshift/56e4ae0e0c1e66cdb7000051/app-root/runtime/repo/

You have to move into the repo directory.

Run gem install bundler.
Run bundle install --no-deployment.
And to be sure, after this, run bundle install.

You should now have nokogiri installed on your host.
Try to launch your application from the URL and you should be able to see the right page with no error.

