How to run an initializer that calls Rails.application?-CodePudding

I've seen posts where the suggestion was to create an initializer or create a config.after_initialize block in the config/application.rb file; however, this doesn't properly work for me because I'm relying on Rails credentials.

For example, I have a class called SlackBot that basically sends a message to our slack channel. I'd like to create an initializer that sends a message once the rails s command is run, but the config.after_initialize doesn't actually work since the SlackBot class pulls creds from Rails.application.credentials

I get the following error when trying to do this:

ubuntu@bf29b8edfeea:~/myapp$ rails s --binding 0.0.0.0 -p 80                                                                                                                                       
=> Booting Puma                                                                                                                                                                                    
=> Rails 6.1.4.4 application starting in development                                                                                                                                               
=> Run `bin/rails server --help` for more startup options                                                                 
Exiting                                                                                                                                              
/usr/local/bundle/gems/activesupport-6.1.4.4/lib/active_support/message_verifier.rb:176:in `verify': ActiveSupport::MessageVerifier::InvalidSignature (ActiveSupport::MessageVerifier::InvalidSignat
ure)                                                                                                                                        
        from /usr/local/bundle/gems/activesupport-6.1.4.4/lib/active_support/message_encryptor.rb:154:in `decrypt_and_verify'
        from /usr/local/bundle/gems/activesupport-6.1.4.4/lib/active_support/messages/rotator.rb:22:in `decrypt_and_verify'
        from /home/ubuntu/myapp/app/helpers/user_helper.rb:19:in `decrypt_data'

The only way I can get rid of this error of course is by removing the custom initializer.

Is there a way that I can call an initializer or method after rails is fully initializer, perhaps as the last step that runs?

CodePudding user response：

According to The Rails Initialization Process of the Rails official reference, the last file to be executed in the initialization sequence is config/environment.rb (Note that although the reference states the last one is config/application.rb, the file should have been in default require-d in the earlier process).

In Rails 6 (or maybe earlier ones, too?), the last line in config/environment.rb is

Rails.application.initialize!

So, if you write your own statements after the line in the file config/environment.rb, your Rails app must have been fully initialized by the time your statements are executed.