当我运行服务器时，它的抛出错误显示在下面的日志中。我在谷歌上搜索了很多，但没有找到背后的原因。有人请点亮它。
gem 文件
source 'https://rubygems.org'
# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '>= 5.0.0.beta1', '< 5.1'
# Use sqlite3 as the database for Active Record
gem 'sqlite3'
gem 'active_model_serializers', '~> 0.10.0.rc1'
group :development, :test do
gem 'byebug'
end
gem 'puma'
group :development do
gem 'spring'
end
日志:
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/server/configuration.rb:15:in
`initialize': uninitialized constant
ActionCable::Server::Configuration::ApplicationCable (NameError) from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/server/base.rb:16:in `new' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/server/base.rb:16:in `block in <class:Base>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/activesupport-5.0.0.beta1/lib/active_support/core_ext/module/attribute_accessors.rb:72:in
`block in mattr_reader' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/activesupport-5.0.0.beta1/lib/active_support/core_ext/module/attribute_accessors.rb:55:in
`each' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/activesupport-5.0.0.beta1/lib/active_support/core_ext/module/attribute_accessors.rb:55:in
`mattr_reader' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/activesupport-5.0.0.beta1/lib/active_support/core_ext/module/attribute_accessors.rb:208:in
`mattr_accessor' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/server/base.rb:16:in `<class:Base>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/server/base.rb:12:in `<module:Server>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/server/base.rb:7:in
`<module:ActionCable>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/server/base.rb:6:in
`<top (required)>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable.rb:43:in
`server' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/actioncable-5.0.0.beta1/lib/action_cable/process/logging.rb:10:in
`<top (required)>' from /home/pd/Documents/EventsApp/config.ru:7:in
`block in <main>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/builder.rb:55:in
`instance_eval' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/builder.rb:55:in
`initialize' from /home/pd/Documents/EventsApp/config.ru:in `new'
from /home/pd/Documents/EventsApp/config.ru:in `<main>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/builder.rb:49:in
`eval' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/builder.rb:49:in
`new_from_string' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/builder.rb:40:in
`parse_file' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/server.rb:318:in
`build_app_and_options_from_config' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/server.rb:218:in
`app' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands/server.rb:56:in
`app' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/rack-2.0.0.alpha/lib/rack/server.rb:353:in
`wrapped_app' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands/server.rb:134:in
`log_to_stdout' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands/server.rb:74:in
`start' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands/commands_tasks.rb:90:in
`block in server' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands/commands_tasks.rb:85:in
`tap' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands/commands_tasks.rb:85:in
`server' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands/commands_tasks.rb:49:in
`run_command!' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/command.rb:20:in
`run' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/railties-5.0.0.beta1/lib/rails/commands.rb:19:in
`<top (required)>' from /home/pd/Documents/EventsApp/bin/rails:9:in
`require' from /home/pd/Documents/EventsApp/bin/rails:9:in `<top
(required)>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/spring-1.6.0/lib/spring/client/rails.rb:28:in
`load' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/spring-1.6.0/lib/spring/client/rails.rb:28:in
`call' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/spring-1.6.0/lib/spring/client/command.rb:7:in
`call' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/spring-1.6.0/lib/spring/client.rb:28:in
`run' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/spring-1.6.0/bin/spring:51:in `<top
(required)>' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/spring-1.6.0/lib/spring/binstub.rb:11:in
`load' from
/home/pd/.rvm/gems/ruby-2.2.4/gems/spring-1.6.0/lib/spring/binstub.rb:11:in
`<top (required)>' from /home/pd/Documents/EventsApp/bin/spring:13:in
`require' from /home/pd/Documents/EventsApp/bin/spring:13:in `<top
(required)>' from bin/rails:3:in `load' from bin/rails:3:in `<main>'
最佳答案
如果你从以前的版本升级(当 actioncable 不在包中时)，检查 config/application.rb 是否包含
require "action_cable/engine"
关于ruby-on-rails - 未初始化常量 > ActionCable::Server::Configuration::ApplicationCable，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/34396006/
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