'rails server'在osx elcapitan上使用mysql 5.7.13返回错误

我是ruby on rails和编程的新手 . 我已按照互联网和设置rails应用程序的说明 . 它是第一次工作，但后来当我重新打开它并试图运行'rails server'时它不起作用并返回跟随错误 . 如果有人帮我解决这个问题，我会很高兴，我一直在互联网上搜索5个小时 . 谢谢 .

我正在使用ruby 2.3.1p112 rails 5.0 mysql 5.7.13 $ rails server

=>引导Puma

=> Rails 5.0.0应用程序在http://localhost:3000开发中开始

=>运行 rails server -h 以获取更多启动选项退出

/Users/bruce/sea/config/routes.rb:6:in`'：undefined

方法`root'for main：Object（NoMethodError）

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/activesupport-

5.0.0 / lib / active_support / dependencies.rb：287：在'load'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/activesupport-

5.0.0 / lib / active_support / dependencies.rb：287：在`block in load'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/activesupport-

5.0.0 / lib / active_support / dependencies.rb：259：在`load_dependency'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/activesupport-

5.0.0 / lib / active_support / dependencies.rb：287：在'load'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/routes_reloader.rb:40：在load_paths中的`block'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/routes_reloader.rb：40：在'每个'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/routes_reloader.rb:40:in,load_paths'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/routes_reloader.rb:16：重新载入！

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/routes_reloader.rb：26：在更新程序中的“块”

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/activesupport-

5.0.0 / lib / active_support / file_update_checker.rb：77：在`execute'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/routes_reloader.rb：27：在'updater'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/routes_reloader.rb：7：在`execute_if_updated'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application/finisher.rb:119:in`block in'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/initializable.rb:30：在`instance_exec'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/initializable.rb:30:in'run'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/initializable.rb：55：在run_initializers中的`block

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:228：在tsort_each中的`block'

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:350：在each_strongly_connected_component中的块（2级）

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:431:in`pert_strongly_connected_component_from'

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:349：在each_strongly_connected_component中的`block'

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:347:in` each'

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:347:in`call'

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:347:in`pert_strongly_connected_component'

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:226:in`tsort_each'

from /Users/bruce/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0

/tsort.rb:205:in`tsort_each'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/initializable.rb：54：在'run_initializers'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/application.rb:352:in`initialize！'

from /Users/bruce/sea/config/environment.rb:5:in `<top (required)>'

from /Users/bruce/sea/config.ru:3:in `require_relative'

from /Users/bruce/sea/config.ru:3:in `block in <main>'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/builder.rb:55:in`instance_eval'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/builder.rb:55:in`initialize'

from /Users/bruce/sea/config.ru:in `new'

from /Users/bruce/sea/config.ru:in `<main>'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/builder.rb:49:in'eval'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/builder.rb:49:in`new_from_string'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/builder.rb:40:in`parse_file'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/server.rb:318:in`build_app_and_options_from_config'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/server.rb:218:in'app'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands/server.rb:59:in`app'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/rack-2.0.1/lib

/rack/server.rb:353:in,peded_app'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands/server.rb:124:in`log_to_stdout'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands/server.rb:77:in`start'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands/commands_tasks.rb:90:in在服务器中阻止'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands/commands_tasks.rb:85:in“tap”

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands/commands_tasks.rb:85:in`server'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands/commands_tasks.rb:49：在`run_command！'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/railties-5.0.0/lib

/rails/commands.rb:18:in`'

from /Users/bruce/sea/bin/rails:9:in `require'

from /Users/bruce/sea/bin/rails:9:in `<top (required)>'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/spring-1.7.2/lib

/spring/client/rails.rb:28:in'load'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/spring-1.7.2/lib

/spring/client/rails.rb:28:in`call'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/spring-1.7.2/lib

/spring/client/command.rb:7:in`call'

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/spring-1.7.2/lib

/spring/client.rb:30：在'run'中

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/spring-1.7.2/bin

/ spring：49：in''

from /Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/spring-1.7.2/lib

/spring/binstub.rb:11:in`load'

来自/Users/bruce/.rvm/gems/ruby-2.3.1@global/gems/spring-1.7.2/lib

/spring/binstub.rb:11:in`'

from /Users/bruce/sea/bin/spring:13:in `require'

from /Users/bruce/sea/bin/spring:13:in `<top (required)>'

from bin/rails:3:in `load'`enter 

from bin/rails:3:in `<main>'