Change SMTP Settings at runtime in your rails application

mail_sender.rb

class MailSender
  def self.send_mail(smtp_settings, user, mail_subject, mail_body)
    options = { :address              => smtp_settings["address"],
                :domain               => smtp_settings["domain"],
                :port                 => smtp_settings["port"].to_i,
                :user_name            => smtp_settings["user_name"],
                :password             => smtp_settings["password"],
                :authentication       => smtp_settings["authentication"],
                :enable_starttls_auto => true,
                :openssl_verify_mode  => 'none'
    }
    Mail.defaults do
      delivery_method :smtp, options
    end

    mail = Mail.new do
      from      smtp_settings["user_name"]
      to        "#{user[:email]}"
      subject   mail_subject
      html_part do
        content_type 'text/html; charset=UTF-8'
        body mail_body
      end
    end

    mail.deliver!
  end
end

user.rb

class User < ActiveRecord::Base
  before_create :send_activation_email

  def send_activation_email
    #.... Collect all your data
    send_mail(mail_template, settings, mail_body)
  end

  def send_mail(mail_template, settings, mail_body)
    smtp_settings = settings.smtp_settings

    if smtp_settings.blank?
      UserMailer.delay.activation_instructions(self, mail_template, mail_body)
    else
      MailSender.delay.send_mail(smtp_settings, self, mail_template["subject"], mail_body)
    end
  end
end

Hey, is this thread safe?

Im looking for a way to set my smtp_settings dynamically and thread safe at the same time, since im running on puma, do you have any hints for me?

thanks!