Rails app with mongoid ... (Mongoid::Errors::NoSessionConfig): No configuration could be found for a session named 'default'

Question

With reference to https://github.com/mongoid/mongoid/issues/2894#issuecomment-14903927 I've done all the necessary changes ... still the issue is there ...

spec_helper.rb file

ENV["RAILS_ENV"] ||= 'test'
require File.expand_path("../../config/environment", FILE)
require 'rspec/rails'
require 'rspec/autorun'
require 'rails/mongoid'

Gemfile

gem 'rails', '4.0.0'
gem 'rspec-rails', '~>2.14.0'
gem 'mongoid', git: 'https://github.com/mongoid/mongoid.git'
gem 'bson_ext'

mongoid.yml

development:
  sessions:
    default:
      database: mongo_demo_development
    hosts:
      - localhost:27017
    options:        
 options:

test:
  sessions:
    default:
      database: mongo_demo_test
      hosts:
        - localhost:27017
      options:
        consistency: :strong      
        max_retries: 1
        retry_interval: 0

Following is the Error Log which is generated when I run my rails server with $rails s ...

/home/nikunj/.rvm/gems/ruby-1.9.3-p385/bundler/gems/mongoid-d52c33bce36a/lib/mongoid/sessions/factory.rb:27:in create': (Mongoid::Errors::NoSessionConfig)
Problem:
No configuration could be found for a session named 'default'.
Summary:
When attempting to create the new session, Mongoid could not find a session configuration for the name: 'default'. This is necessary in order to know the host, port, and options needed to connect.
Resolution:
Double check your mongoid.yml to make sure under the sessions key that a configuration exists for 'default'. If you have set the configuration programatically, ensure that 'default' exists in the configuration hash.
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Answer 1

Your mongoid.yml has an error "hosts:" key should be inside of "default:" because it is a required configuration for sessions

Please check http://mongoid.org/en/mongoid/docs/installation.html#configuration