MongoMapper and bson_ext problem

Question

I can\'t get MongoMapper to work with my Rails app. I get this error message:

**Notice: C extension not loaded. This is required for optimum MongoDB Ruby driver performa

Answer 1

The problem is: the bson_ext gem version and the mongo gem version need to match, also, mongo_mapper isn't ready for mongo-1.0.1 yet, so the versions of the mongo and bson_ext gems you should be using are 1.0 for each, respectively.

so, do the following:

gem install mongo -v=1.0 --no-ri --no-rdoc && \
gem install bson_ext -v=1.0 --no-ri --no-rdoc

then for Rails 2.x in your config/environment.rb do:

config.gem 'mongo', :version => '1.0'
config.gem 'bson_ext', :version => '1.0'

or for Rails 3, in your Gemfile:

gem 'mongo', '1.0'
gem 'bson_ext', '1.0'

Answer 2

1. Install bson_ext using:

   gem install bson_ext
   

2. Add the gem to your Gemfile:

   gem 'bson_ext'
   

3. Run bundle in your project root level directory.

Answer 3

Include the following in your environment.rb

config.gem 'bson_ext', :version => "1.0", :lib => "bson_ext/cbson"

Answer 4

I followed the instructions above but still the "no such file to load 'bson_ext'. I went to the gem and tried moving the folders in the "ext" folder up one level (to the root of the gem) and lo and behold, it worked. FWIW...

Answer 5

I needed specify the bson version to get this to work, like so:

gem 'mongo', "1.1"
gem 'bson', "1.1"
gem 'bson_ext', "1.1"

(Using rails 3)

Answer 6

This is generally caused by installing a version of bson_ext not equal to the version number required by MongoMapper. Check which version of bson MongoMapper is requiring, and then make sure that you have that version and no other installed.