Rest-Client將不會為Ruby安裝

Question

我正在嘗試使用rest-client gem安裝運行Ruby應用程序。 我不斷收到錯誤消息：

C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows/root_certs.rb:2:in `require': cannot load such file -- ffi (LoadError)
    from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows/root_certs.rb:2:in `<top (required)>'
    from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows.rb:7:in `require_relative'
    from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows.rb:7:in `<top (required)>'
    from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient.rb:16:in `require'
    from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient.rb:16:in `<top (required)>'
    from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/rest-client.rb:2:in `require'
    from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/rest-client.rb:2:in `<top (required)>'
    from app.rb:6:in `require'
    from app.rb:6:in `<main>'

$ ./start ruby
Installing bundle
Starting server
C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows/root_certs.rb:2:in `require': cannot load such file -- ffi (LoadError)
        from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows/root_certs.rb:2:in `<top (required)>'
        from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows.rb:7:in `require_relative'
        from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient/windows.rb:7:in `<top (required)>'
        from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient.rb:16:in `require'
        from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/restclient.rb:16:in `<top (required)>'
        from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/rest-client.rb:2:in `require'
        from C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rest-client-1.8.0/lib/rest-client.rb:2:in `<top (required)>'
        from app.rb:6:in `require'
        from app.rb:6:in `<main>'

但是我確定安裝了gem：

rest-client (2.0.0.rc2, 1.8.0)
rest-open-uri (1.0.0)
rest_client (1.8.3)

有誰知道我在安裝過程中做錯了什么？

Answer 1

問題是未安裝FFI，這是我收到錯誤消息的原因。 不幸的是使用

bundle install

沒有正確安裝它，我必須手動安裝gem（安裝時間比預期的長得多

 gem install ffi