DEV: Add env var for local email port (#36900)

This commit adds DISCOURSE_LOCAL_EMAIL_PORT
environment variable to allow setting a port other than 1025 for local
mail.
This is added because now macOS has a system service using port 1025,
causing conflicts when running a local mail server for Discourse
development.

config/environment.rb

@@ -8,6 +8,7 @@ Rails.application.initialize!
 
 # When in "dev" mode, ensure we won't be sending any emails
 if Rails.env.development? && !GlobalSetting.try(:use_smtp_environment_in_development) &&
-     ActionMailer::Base.smtp_settings.slice(:address, :port) != { address: "localhost", port: 1025 }
+     ActionMailer::Base.smtp_settings.slice(:address, :port) !=
+       { address: "localhost", port: ENV["DISCOURSE_LOCAL_EMAIL_PORT"] || 1025 }
   fail "In development mode, you should be using a local development mail server to avoid unintentionally sending real mail"
 end

config/environments/development.rb

@@ -39,10 +39,11 @@ Discourse::Application.configure do
 
   config.action_mailer.smtp_settings =
     if GlobalSetting.try(:use_smtp_environment_in_development)
-      GlobalSetting.smtp_settings || { address: "localhost", port: 1025 }
+      GlobalSetting.smtp_settings ||
+        { address: "localhost", port: ENV["DISCOURSE_LOCAL_EMAIL_PORT"] || 1025 }
     else
       # we recommend you use mailpit: https://github.com/axllent/mailpit/
-      { address: "localhost", port: 1025 }
+      { address: "localhost", port: ENV["DISCOURSE_LOCAL_EMAIL_PORT"] || 1025 }
     end
 
   config.action_mailer.raise_delivery_errors = true

config/environments/profile.rb

@@ -30,7 +30,10 @@ Discourse::Application.configure do
   config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for nginx
 
   # we recommend you use mailhog https://github.com/mailhog/MailHog
-  config.action_mailer.smtp_settings = { address: "localhost", port: 1025 }
+  config.action_mailer.smtp_settings = {
+    address: "localhost",
+    port: ENV["DISCOURSE_LOCAL_EMAIL_PORT"] || 1025,
+  }
 
   # Send deprecation notices to registered listeners
   config.active_support.deprecation = :notify