default_url_options

🔗 Configure default_url_options in Environments

Links in mailers need full URLs (host, protocol). Set default_url_options in your environment configs to avoid missing host errors.

# config/environments/development.rb
Rails.application.routes.default_url_options = { host: 'localhost', port: 3000 }
# config/environments/production.rb
Rails.application.routes.default_url_options = { host: 'example.com', protocol: 'https' }

Now helpers like edit_user_url(@user) in your mailer views generate absolute URLs automatically.