discourse/app/mailers/rejection_mailer.rb

# frozen_string_literal: true

require "email/message_builder"

class RejectionMailer < ActionMailer::Base
  include Email::BuildEmailHelper

  DISALLOWED_TEMPLATE_ARGS = %i[
    to
    from
    base_url
    user_preferences_url
    include_respond_instructions
    html_override
    add_unsubscribe_link
    respond_instructions
    style
    body
    post_id
    topic_id
    subject
    template
    allow_reply_by_email
    private_reply
    from_alias
  ]

  # Send an email rejection message.
  #
  # template - i18n key under system_messages
  # message_from - Who to send the rejection message to
  # template_args - arguments to pass to i18n for interpolation into the message
  #     Certain keys are disallowed in template_args to avoid confusing the
  #     BuildEmailHelper. You can see the list in DISALLOWED_TEMPLATE_ARGS.
  def send_rejection(template, message_from, template_args)
    if template_args.keys.any? { |k| DISALLOWED_TEMPLATE_ARGS.include? k }
      raise ArgumentError.new("Reserved key in template arguments")
    end

    build_email(message_from, template_args.merge(template: "system_messages.#{template}"))
  end
end