在materialize中，块在任何源代码rails中都找不到multi_json-1.8.0

Here is my deploy.rb

这是我deploy.rb

require "bundler/capistrano"

set :rvm_ruby_string, "ruby-2.0.0-p247"
set :rvm_type, :user

set :application, "myapp"
set :repository,  "[email protected]:user/myapp.git"
set :user, "my-server-username-ssh"
set :branch, "master"

set :deploy_to, "/var/rails_apps/myapp"  # I have current, release and shared directory here
set :deploy_via, :copy
set :use_sudo, true
set :rvm_install_with_sudo, true

default_run_options[:pty] = true

set :port, 1234

set :scm, :git

role :web, "myapp.com"
role :app, "myapp.com"
role :db,  "myapp.com", :primary => true
role :db,  "myapp.com"

after "deploy:update_code","deploy:config_symlink"

set :rvm_type, :system

# If you are using Passenger mod_rails uncomment this:
namespace :deploy do
  task :start do ; end
  task :stop do ; end
  task :restart, :roles => :app, :except => { :no_release => true } do
    run "#{try_sudo} touch #{File.join(current_path,'tmp','restart.txt')}"
  end

  task :config_symlink do
    #run "cp #{release_path}/config/database.yml.example #{release_path}/config/database.yml"
  end

  desc 'Re-establish database.yml'
  task :set_database_symlink do
    run "rm -fr #{current_path}/config/database.yml && cd #{current_path}/config &&
        ln -nfs #{shared_path}/database.yml database.yml" 
  end
end

before 'deploy', 'rvm:install_ruby'
before 'deploy', 'rvm:create_gemset'

require "rvm/capistrano"
require "