ruby on rails - WebHDFS::ServerError when using webhdfs to access HDFS -

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i'm using ror3 , webhdfs build web site access hdfs, when i'm using webhdfs in users_controller, webhdfs::servererror response body empty.. response.

my userscontroller code is:

class userscontroller < applicationcontroller ... ...   def create     @user = user.new(params[:user])     # create directory in hdfs user     webhdfs = webhdfs::client.new('lhy-namenode', 50070, 'lhy')     webhdfs.mkdir('abc')     if @user.save       flash[:success] = "welcome"       redirect_to @user     else       render 'new'     end   end ... end

and error message occurs when click submit button create new user. shows:

webhdfs::servererror in userscontroller#create response body empty..

i don't know now, can me? thank much!


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