raise_in_transactional_callbacks 回形针问题 (rails 4.2)
raise_in_transactional_callbacks issue with paperclip (rails 4.2)
我已经更新到 rails 4.2。当我跟进弃用警告并在我的环境中设置 config.active_record.raise_in_transactional_callbacks = true 时，我开始 运行 问题：
Failure/Error: Unable to find matching line from backtrace
NoMethodError:
undefined method `id' for nil:NilClass
ID 指的是 current_user.id，它已变得不可用（因此在错误跟踪中提及 warden 和 devise）。
删除 config.active_record.raise_in_transactional_callbacks = true 时，弃用警告仅针对使用回形针的两个模型出现，这让我相信这可能是回形针回调的问题。我可以忽略弃用警告，但我宁愿解决潜在的问题。有什么建议吗？
这是一个错误跟踪：
commpleted 500 Internal Server Error in 152ms
Unexpected error while processing request: undefined method `env' for nil:NilClass
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/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/connection.rb:39:in `receive_data'
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/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/server.rb:286:in `start'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/server.rb:80:in `start'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:80:in `block in server'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `tap'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `server'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands.rb:17:in `<top (required)>'
bin/railre'
这是与您所说的相关的问题：https://github.com/thoughtbot/paperclip/issues/1933 (especially my comments : https://github.com/thoughtbot/paperclip/issues/1933#issuecomment-169607838 and https://github.com/thoughtbot/paperclip/issues/1933#issuecomment-170509222 )
请注意这个警告不是错误，它只是告诉你 ActiveRecord 的未来行为，这不是浅错误。
删除 config.active_record.raise_in_transactional_callbacks = true 将向您显示 after_commit / after_rollback 的警告并切换到旧行为，这是浅化错误。
我已经更新到 rails 4.2。当我跟进弃用警告并在我的环境中设置 config.active_record.raise_in_transactional_callbacks = true 时，我开始 运行 问题：
Failure/Error: Unable to find matching line from backtrace
NoMethodError:
undefined method `id' for nil:NilClass
ID 指的是 current_user.id，它已变得不可用（因此在错误跟踪中提及 warden 和 devise）。
删除 config.active_record.raise_in_transactional_callbacks = true 时，弃用警告仅针对使用回形针的两个模型出现，这让我相信这可能是回形针回调的问题。我可以忽略弃用警告，但我宁愿解决潜在的问题。有什么建议吗？
这是一个错误跟踪：
commpleted 500 Internal Server Error in 152ms
Unexpected error while processing request: undefined method `env' for nil:NilClass
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/Users/j/.rvm/gems/ruby-2.1.2/gems/actionpack-4.2.0/lib/action_dispatch/middleware/callbacks.rb:27:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/actionpack-4.2.0/lib/action_dispatch/middleware/reloader.rb:73:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/actionpack-4.2.0/lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/actionpack-4.2.0/lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/actionpack-4.2.0/lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/rack/logger.rb:38:in `call_app'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/rack/logger.rb:20:in `block in call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/activesupport-4.2.0/lib/active_support/tagged_logging.rb:68:in `block in tagged'
/Users/j/.rvm/gems/ruby-2.1.2/gems/activesupport-4.2.0/lib/active_support/tagged_logging.rb:26:in `tagged'
/Users/j/.rvm/gems/ruby-2.1.2/gems/activesupport-4.2.0/lib/active_support/tagged_logging.rb:68:in `tagged'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/rack/logger.rb:20:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/actionpack-4.2.0/lib/action_dispatch/middleware/request_id.rb:21:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/methodoverride.rb:22:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/runtime.rb:18:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/activesupport-4.2.0/lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/lock.rb:17:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/actionpack-4.2.0/lib/action_dispatch/middleware/static.rb:113:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/sendfile.rb:113:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/engine.rb:518:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/application.rb:164:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/content_length.rb:15:in `call'
/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/connection.rb:86:in `block in pre_process'
/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/connection.rb:84:in `catch'
/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/connection.rb:84:in `pre_process'
/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/connection.rb:53:in `process'
/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/connection.rb:39:in `receive_data'
/Users/j/.rvm/gems/ruby-2.1.2/gems/eventmachine-1.0.7/lib/eventmachine.rb:187:in `run_machine'
/Users/j/.rvm/gems/ruby-2.1.2/gems/eventmachine-1.0.7/lib/eventmachine.rb:187:in `run'
/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/backends/base.rb:73:in `start'
/Users/j/.rvm/gems/ruby-2.1.2/gems/thin-1.6.3/lib/thin/server.rb:162:in `start'
/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/handler/thin.rb:19:in `run'
/Users/j/.rvm/gems/ruby-2.1.2/gems/rack-1.6.0/lib/rack/server.rb:286:in `start'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/server.rb:80:in `start'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:80:in `block in server'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `tap'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `server'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
/Users/j/.rvm/gems/ruby-2.1.2/gems/railties-4.2.0/lib/rails/commands.rb:17:in `<top (required)>'
bin/railre'
这是与您所说的相关的问题：https://github.com/thoughtbot/paperclip/issues/1933 (especially my comments : https://github.com/thoughtbot/paperclip/issues/1933#issuecomment-169607838 and https://github.com/thoughtbot/paperclip/issues/1933#issuecomment-170509222 )
请注意这个警告不是错误，它只是告诉你 ActiveRecord 的未来行为，这不是浅错误。
删除 config.active_record.raise_in_transactional_callbacks = true 将向您显示 after_commit / after_rollback 的警告并切换到旧行为，这是浅化错误。