application.rb语法错误,意外的“,”,应为“)”

我有一个Rails5API模式应用程序。

my config/application.rb如下所示:

添加application.rb

  module Myapi
  class Application < Rails::Application
    # Initialize configuration defaults for originally generated Rails version.
    config.load_defaults 5.1



    # Settings in config/environments/* take precedence over those specified here.
    # Application configuration should go into files in config/initializers
    # -- all .rb files in that directory are automatically loaded.

    # Only loads a smaller set of middleware suitable for API only apps.
    # Middleware like session, flash, cookies can be added back manually.
    # Skip views, helpers and assets when generating a new resource.
    config.api_only = true
    config.middleware.insert_before 0, Rack::Cors do
      allow do
        origins '*'
        resource (
          '*', 
          headers: :any, 
          methods: [:get, :patch, :put, :delete, :post, :options]
        )
      end
    end
  end
end

但我得到了以下错误:

.gem/ruby/2.5.1/gems/railties-5.1.6/lib/rails/commands/server/server_command.rb:133:in `require': 


ndflo-api/goforfloapi/config/application.rb:38: syntax error, unexpected ',', expecting ')' (SyntaxError)
          '*', 

导致此语法错误的第38行的语法有什么问题?

第38行如下:

'*',