Rails with Mongo Mapper - ruby-on-rails

Question

This is turning out to be the worst day for learning rails. Already failed to connect and configure to sqlite3, mysql databases I turned to mongo mapper and facing the same issues. When I try to start the rails server I get the following:
/usr/local/lib/ruby/gems/1.8/gems/activesupport-3.0.7/lib/active_support/dependencies.rb:239:in `require': no such file to load -- mongo_mapper (LoadError)
I have already installed mongo_mapper gem but when I do 'which mongo_mapper' it does not return anything.
Here is my mongo_config.rb file placed inside the initializers folder:
require "rubygems"
require "mongo_mapper"
MongoMapper.database = "blog-#{Rails.env}"
UPDATE 1:
I changed to the following:
require "rubygems"
include MongoMapper
MongoMapper.database = "blog-#{Rails.env}"
And now I get the following error:
/Users/azamsharp/Projects/railsprojects/blog/config/initializers/mongo_config.rb:2: uninitialized constant MongoMapper (NameError)

Answer 1

You must use bundler with rails 3. don't try to not use it. add the following to your Gemfile
source 'http://gemcutter.org'
source 'http://rubygems.org'
gem "rails", "3.0.7"
gem 'bson', "1.1.1"
gem 'bson_ext', "1.1.1"
gem 'mongo_mapper'
then run
bundle install
then rails server will work

Answer 2

In order to get mongo_mapper working in Rails (tested under Rails 3.1, should work in Rails 3.0.x as well), you have to follow these steps:
In Gemfile, add the mongo_mapper and bson gem:
gem 'mongo_mapper'
gem 'bson_ext'
Run bundle install
In the config/ directory, create a mongo.yml file like this one:
# config/mongo.yml
defaults: &defaults
host: 127.0.0.1
port: 27017
development:
<<: *defaults
database: db_development
username: user
password: password
test:
<<: *defaults
database: db_test
# set these environment variables on your prod server
production:
<<: *defaults
database:
username:
password:
In the config/initializers directory, create a mongo.rb file like this:
# config/initializers/mongo.rb
#include MongoMapper
db_config = YAML::load(File.read(File.join(Rails.root, "/config/mongo.yml")))
#
if db_config[Rails.env] && db_config[Rails.env]['adapter'] == 'mongodb'
mongo = db_config[Rails.env]
MongoMapper.connection = Mongo::Connection.new(mongo['host'] || 'localhost',
mongo['port'] || 27017,
:logger => Rails.logger)
MongoMapper.database = mongo['database']
if mongo['username'] && mongo['password']
MongoMapper.database.authenticate(mongo['username'], mongo['password'])
end
end
# Used for image uploads
# CarrierWave.configure do |config|
# mongo = db_config[Rails.env]
# config.grid_fs_database = mongo['database']
# config.grid_fs_host = mongo['host'] || 'localhost'
# config.grid_fs_access_url = "gridfs"
# config.grid_fs_username = mongo['username']
# config.grid_fs_password = mongo['password']
# end
# It's also possible to define indexes in the the model itself; however,
# a few issues are being worked out still. This is a temporary solution.
# Comment.ensure_index([["story_id", 1], ["path", 1], ["points", -1]])
# MongoMapper.ensure_indexes!
# Handle passenger forking.
# if defined?(PhusionPassenger)
# PhusionPassenger.on_event(:starting_worker_process) do |forked|
# MongoMapper.database.connect_to_master if forked
# end
# end
if defined?(PhusionPassenger)
PhusionPassenger.on_event(:starting_worker_process) do |forked|
MongoMapper.connection.connect if forked
end
end
Start the mongod server before starting the rails server and enjoy!

Answer 3

Try removing the require lines and replace them with include MongoMapper