エラーが必要です。そのようなファイルをロードすることはできません - mongomapper（とLoadError）とシナトラアプリを起動したら

Question

を開始するためには考えて、私は次のようなエラーメッセージが出ます：

/home/matt/.rvm/gems/ruby-1.9.3-p125/gems/backports-2.5.1/lib/backports/tools.rb:310:in `require': cannot load such file -- mongomapper (LoadError) 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/backports-2.5.1/lib/backports/tools.rb:310:in `require_with_backports' 
    from /home/matt/handle-phone-call/app.rb:10:in `<top (required)>' 
    from /home/matt/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require' 
    from /home/matt/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require' 
    from /home/matt/handle-phone-call/config.ru:2:in `block in <main>' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/builder.rb:51:in `instance_eval' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/builder.rb:51:in `initialize' 
    from /home/matt/handle-phone-call/config.ru:1:in `new' 
    from /home/matt/handle-phone-call/config.ru:1:in `<main>' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/builder.rb:40:in `eval' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/builder.rb:40:in `parse_file' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/server.rb:200:in `app' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/server.rb:301:in `wrapped_app' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/server.rb:252:in `start' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/lib/rack/server.rb:137:in `start' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/gems/rack-1.4.1/bin/rackup:4:in `<top (required)>' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/bin/rackup:19:in `load' 
    from /home/matt/.rvm/gems/ruby-1.9.3-p125/bin/rackup:19:in `<main>' 

任意のアイデア？私はどこから始めなければならないのか分かりません。

Answer 1

mongo_mapper（mongomapperではなく）が必要です。