我正在关注来自 http://learn-rails.com/ 的 learn-rails 教程书 2
I'm following the learn-rails tutorial book 2 from http://learn-rails.com/
我是初学者！
当我启动 rails server:
时，我在终端中不断收到此错误
rails server localhost:3000
Exiting
/Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/handler.rb:78:in `require': cannot load such file -- rack/handler/localhost:3000 (LoadError)
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/handler.rb:78:in `try_require'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/handler.rb:16:in `get'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/server.rb:290:in `server'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/server.rb:125:in `print_boot_information'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/server.rb:75:in `start'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:80:in `block in server'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `tap'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `server'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands.rb:17:in `<top (required)>'
from /Users/michael/Projects/RailsApps/learn-rails/bin/rails:9:in `require'
from /Users/michael/Projects/RailsApps/learn-rails/bin/rails:9:in `<top (required)>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client/rails.rb:28:in `load'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client/rails.rb:28:in `call'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client/command.rb:7:in `call'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client.rb:30:in `run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/bin/spring:49:in `<top (required)>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/binstub.rb:11:in `load'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/binstub.rb:11:in `<top (required)>'
from /Users/michael/Projects/RailsApps/learn-rails/bin/spring:13:in `require'
from /Users/michael/Projects/RailsApps/learn-rails/bin/spring:13:in `<top (required)>'
from bin/rails:3:in `load'
from bin/rails:3:in `<main>'
我使用的是 2013 款 MacBook Air 运行 OSX EL Cap 10.11.6
rvm 1.27.0
ruby2.3.1
rails 4.2.5
我是来自 Projects/RailsApps/learn-rails 的 运行 rails 服务器。我正在学习第 10 章的配置，并在 .bashrc 中设置了我的环境变量，并配置了 config/secrets.yml 文件以从环境变量中提取。
我曾尝试使用谷歌搜索寻求帮助，但找不到任何相关的答案。
我也无法在 SO 或 Quora 上找到可以帮助我的答案。
**更新
这是我在 运行 'bundle' 和 'rails g simple_form:install'
之后收到的错误消息
Michaels-MacBook-Air:learn-rails michael$ rails g simple_form:install
[Simple Form] Simple Form is not configured in the application and will use the default values. Use `rails generate simple_form:install` to generate the Simple Form configuration.
/Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/erb.rb:864:in `eval': (erb):15: syntax error, unexpected '=', expecting end-of-input
; =ENV["SENDGRID_PASSWORD"] ; _e...
^ (SyntaxError)
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/erb.rb:864:in `result'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:391:in `secrets'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:178:in `key_generator'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:206:in `message_verifier'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/globalid-0.3.7/lib/global_id/railtie.rb:25:in `block (2 levels) in <class:Railtie>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:45:in `block in run_load_hooks'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:44:in `each'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:44:in `run_load_hooks'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application/finisher.rb:62:in `block in <module:Finisher>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `instance_exec'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:55:in `block in run_initializers'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:228:in `block in tsort_each'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:350:in `block (2 levels) in each_strongly_connected_component'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:431:in `each_strongly_connected_component_from'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:349:in `block in each_strongly_connected_component'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:347:in `each'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:347:in `call'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:347:in `each_strongly_connected_component'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:226:in `tsort_each'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:205:in `tsort_each'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:54:in `run_initializers'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:352:in `initialize!'
from /Users/michael/Projects/RailsApps/learn-rails/config/environment.rb:5:in `<top (required)>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:92:in `require'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:92:in `preload'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:143:in `serve'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:131:in `block in run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:125:in `loop'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:125:in `run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application/boot.rb:19:in `<top (required)>'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from -e:1:in `<main>'
我检查了我的 gemfile。 gem simple_form 已从 gemfile 中列出并取消注释。
我认为在你的 secrets.yml 文件中，你有这样的东西。
<% =ENV["SENDGRID_PASSWORD"] %>
=ENV["SENDGRID_PASSWORD"] 不是有效的 ruby 表达式，这就是您收到错误的原因。
其实应该是
<%= ENV["SENDGRID_PASSWORD"] %>
希望对您有所帮助！
我是初学者！
当我启动 rails server:
时，我在终端中不断收到此错误rails server localhost:3000
Exiting
/Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/handler.rb:78:in `require': cannot load such file -- rack/handler/localhost:3000 (LoadError)
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/handler.rb:78:in `try_require'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/handler.rb:16:in `get'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/rack-1.6.4/lib/rack/server.rb:290:in `server'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/server.rb:125:in `print_boot_information'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/server.rb:75:in `start'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:80:in `block in server'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `tap'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:75:in `server'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/commands.rb:17:in `<top (required)>'
from /Users/michael/Projects/RailsApps/learn-rails/bin/rails:9:in `require'
from /Users/michael/Projects/RailsApps/learn-rails/bin/rails:9:in `<top (required)>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client/rails.rb:28:in `load'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client/rails.rb:28:in `call'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client/command.rb:7:in `call'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/client.rb:30:in `run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/bin/spring:49:in `<top (required)>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/binstub.rb:11:in `load'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/binstub.rb:11:in `<top (required)>'
from /Users/michael/Projects/RailsApps/learn-rails/bin/spring:13:in `require'
from /Users/michael/Projects/RailsApps/learn-rails/bin/spring:13:in `<top (required)>'
from bin/rails:3:in `load'
from bin/rails:3:in `<main>'
我使用的是 2013 款 MacBook Air 运行 OSX EL Cap 10.11.6 rvm 1.27.0 ruby2.3.1 rails 4.2.5 我是来自 Projects/RailsApps/learn-rails 的 运行 rails 服务器。我正在学习第 10 章的配置，并在 .bashrc 中设置了我的环境变量，并配置了 config/secrets.yml 文件以从环境变量中提取。 我曾尝试使用谷歌搜索寻求帮助，但找不到任何相关的答案。 我也无法在 SO 或 Quora 上找到可以帮助我的答案。
**更新 这是我在 运行 'bundle' 和 'rails g simple_form:install'
之后收到的错误消息Michaels-MacBook-Air:learn-rails michael$ rails g simple_form:install
[Simple Form] Simple Form is not configured in the application and will use the default values. Use `rails generate simple_form:install` to generate the Simple Form configuration.
/Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/erb.rb:864:in `eval': (erb):15: syntax error, unexpected '=', expecting end-of-input
; =ENV["SENDGRID_PASSWORD"] ; _e...
^ (SyntaxError)
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/erb.rb:864:in `result'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:391:in `secrets'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:178:in `key_generator'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:206:in `message_verifier'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/globalid-0.3.7/lib/global_id/railtie.rb:25:in `block (2 levels) in <class:Railtie>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:45:in `block in run_load_hooks'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:44:in `each'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/activesupport-4.2.5/lib/active_support/lazy_load_hooks.rb:44:in `run_load_hooks'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application/finisher.rb:62:in `block in <module:Finisher>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `instance_exec'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:30:in `run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:55:in `block in run_initializers'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:228:in `block in tsort_each'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:350:in `block (2 levels) in each_strongly_connected_component'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:431:in `each_strongly_connected_component_from'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:349:in `block in each_strongly_connected_component'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:347:in `each'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:347:in `call'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:347:in `each_strongly_connected_component'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:226:in `tsort_each'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/2.3.0/tsort.rb:205:in `tsort_each'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/initializable.rb:54:in `run_initializers'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/railties-4.2.5/lib/rails/application.rb:352:in `initialize!'
from /Users/michael/Projects/RailsApps/learn-rails/config/environment.rb:5:in `<top (required)>'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:92:in `require'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:92:in `preload'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:143:in `serve'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:131:in `block in run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:125:in `loop'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application.rb:125:in `run'
from /Users/michael/.rvm/gems/ruby-2.3.1@learn-rails/gems/spring-1.7.2/lib/spring/application/boot.rb:19:in `<top (required)>'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from /Users/michael/.rvm/rubies/ruby-2.3.1/lib/ruby/site_ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from -e:1:in `<main>'
我检查了我的 gemfile。 gem simple_form 已从 gemfile 中列出并取消注释。
我认为在你的 secrets.yml 文件中，你有这样的东西。
<% =ENV["SENDGRID_PASSWORD"] %>
=ENV["SENDGRID_PASSWORD"] 不是有效的 ruby 表达式，这就是您收到错误的原因。
其实应该是
<%= ENV["SENDGRID_PASSWORD"] %>
希望对您有所帮助！