Add Run Some Code When Rails Console Starts as a Rails til

README.md

@@ -10,7 +10,7 @@ pairing with smart people at Hashrocket.
 
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@@ -772,6 +772,7 @@ _1196 TILs and counting..._
 - [Retrieve An Object If It Exists](rails/retrieve-an-object-if-it-exists.md)
 - [Rollback A Specific Migration Out Of Order](rails/rollback-a-specific-migration-out-of-order.md)
 - [Rounding Numbers With Precision](rails/rounding-numbers-with-precision.md)
+- [Run Some Code Whenever Rails Console Starts](rails/run-some-code-whenever-rails-console-starts.md)
 - [Schedule Sidekiq Jobs Out Into The Future](rails/schedule-sidekiq-jobs-out-into-the-future.md)
 - [Secure Passwords With Rails And Bcrypt](rails/secure-passwords-with-rails-and-bcrypt.md)
 - [Select A Select By Selector](rails/select-a-select-by-selector.md)

rails/run-some-code-whenever-rails-console-starts.md

@@ -0,0 +1,36 @@
+# Run Some Code Whenever Rails Console Starts
+
+It can be handy to run some code whenever the `rails console` command is run.
+You may want to have some modules required, some variables set up, or, both
+fancy and practical, default to the read replica database in production.
+
+Rails provides a hook into the console startup with the `console` block in
+`config/application.rb`.
+
+Here is what it looks like to `puts` out the environment:
+
+```ruby
+class Application < Rails::Application
+  # everything else ...
+
+  console do
+    puts '############################################'
+    puts 'Connected to the #{Rails.env.upcase} console'
+    puts '############################################'
+  end
+end
+```
+
+To avoid cluttering `config/application.rb` with a bunch of console-specific
+logic, you can move it to another file and then have the console block require
+that file with the `-r` flag.
+
+```ruby
+class Application < Rails::Application
+  console do
+    ARGV.push "-r", Rails.root.join("lib/console.rb")
+  end
+end
+```
+
+[source](https://til.hashrocket.com/posts/avb2v3ubdt-pass-a-block-on-console-load)