在Rails - config/application.rb或config/environments/#{RAILS_ENV}.rb中，哪个配置文件优先？

Question

在rails配置中，当面临冲突的配置选项时，您可以将配置设置放在config/application.rb或config/environments/#{production|staging|development}.rb中，哪个文件的配置选项是赢家？

Answer 1

特定于环境的配置优先于application.rb。您可以在Rails::Application的文档中看到这一点。初始加载(点3)发生在application.rb中，环境有机会覆盖点5中的负载。

Booting process
The application is also responsible for setting up and executing the booting process. From the moment you require “config/application.rb” in your app, the booting process goes like this:

1)  require "config/boot.rb" to set up load paths
2)  require railties and engines
3)  Define Rails.application as "class MyApp::Application < Rails::Application"
4)  Run config.before_configuration callbacks
5)  Load config/environments/ENV.rb
6)  Run config.before_initialize callbacks
7)  Run Railtie#initializer defined by railties, engines and application.
    One by one, each engine sets up its load paths, routes and runs its config/initializers/* files.
8)  Custom Railtie#initializers added by railties, engines and applications are executed
9)  Build the middleware stack and run to_prepare callbacks
10) Run config.before_eager_load and eager_load! if eager_load is true
11) Run config.after_initialize callbacks

来源：https://api.rubyonrails.org/classes/Rails/Application.html

Answer 2

config/application.rb胜过所有配置选项。我做了一个快速测试，pp "application"在config/application.rb中，pp "environment"在config/environments/development.rb中。还设置了2个冲突的配置选项。

发现首先加载环境配置文件，从而允许application.rb中的配置被覆盖并成为配置的最终结果。