class ExampleMailer < ApplicationMailer

def sample_email(user)
    @user = user
    mailgun_client = Mailgun::Client.new ENV['MAILGUN_API_KEY']
    message_params = {:from     => ENV['GMAIL_USERNAME'],
                      :to       => @user.email,
                      :subject  => 'Sample Mail Using Mailgun API',
                      :text     => 'Testing...'}

    mailgun_client.send_message ENV['MAILGUN_DOMAIN'], message_params

  end
end

MAILGUN_API_KEY:  '[REDACTED]'
MAILGUN_ADDRESS:  'smtp.mailgun.org'
MAILGUN_PORT:     587
MAILGUN_DOMAIN:   '[REDACTED]'
MAILGUN_USERNAME: '[REDACTED]'
MAILGUN_PASSWORD: '[REDACTED]'
GMAIL_USERNAME:   '[REDACTED]'