paytriot.co.uk payment gateway example

paytriots.rb

require "ostruct"
require 'digest'
require 'faraday'


module Payments

  class Paytriots
    # Environment variables
    #
    # Required:
    #   - PAYTRIOT_SERVICE_URL
    #   - PAYTRIOT_SECRET
    #   - PAYTRIOT_KEY
    #   - PAYTRIOT_DES_KEY
    #   - PAYTRIOT_ACCOUNT_ID
    #
    # Optional:
    #   - PAYTRIOT_CURRENCY
    #   - PAYTRIOT_PAYMENT_TYPE
    #
    # Encryption:
    #   - md5 is primary encryption

    ENV_NAMESPACE = 'PAYTRIOT'

    DEFAULT_SERVICE_URL = 'https://api.paytriot.co.uk/api/merchant'
    DEFAULT_VERSION = '1.0';
    DEFAULT_PAYMENT_TYPE = 'creditcard'
    DEFAULT_CURRENCY = 'EUR'
    DEFAULT_DEPOSIT_CATEGORY = '3'
    DEFAULT_NO_EXPIRATION = 0

    # Errors happened on missing required configurations
    ERROR_SECRET_REQUIRED = 'secret is required'
    ERROR_KEY_REQUIRED = 'key is required'
    ERROR_DES_KEY_REQUIRED = 'des key is required'
    ERROR_ACCOUNT_ID_REQUIRED = 'account id is required'

    TEST_MODE_ENABLED = 1

    class << self
      def create_payment_url(
        amount:,
        type: nil,
        currency: nil,
        deposit_category: nil,
        url_user_on_success: nil,
        url_user_on_fail: nil,
        url_api_on_success: nil,
        url_api_on_fail: nil,
        no_expiration: nil
      )
        params = {}

        # payment arguments
        params[:amount] = amount
        params[:type] = settings.payment_type || type
        params[:currency] = settings.currency || currency
        params[:account_id] = settings.account_id
        params[:deposit_category] = settings.deposit_category || deposit_category

        # callbacks
        params[:url_user_on_success] = url_user_on_success
        params[:url_user_on_fail] = url_user_on_fail
        params[:url_api_on_success] = url_api_on_success
        params[:url_api_on_fail] = url_api_on_fail
        params[:no_expiration] = no_expiration || DEFAULT_NO_EXPIRATION

        request('create_payment_request_link', params)
      end

      def request(service_name, params)
        params[:test] = TEST_MODE_ENABLED if settings.test_mode

        # add signature to params
        params = sign(params)

        url = get_url(service_name)

        response = Faraday.post(url, params.to_json, {'Content-Type' => 'application/json; charset=utf-8'})

        JSON.parse(response.body, symbolize_names: true)
      end

      def get_url(service_name)
        "#{settings.service_url}/v/#{DEFAULT_VERSION}/function/#{service_name}"
      end

      def settings
        @settings ||= begin
          _settings = OpenStruct.new(
            {
              secret: get_env('secret'),
              key: get_env('key'),
              des_key: get_env('des_key'),
              account_id: get_env('account_id'),
              service_url: get_env('service_url', DEFAULT_SERVICE_URL),
              payment_type: get_env('type', DEFAULT_PAYMENT_TYPE),
              currency: get_env('currency', DEFAULT_CURRENCY),
              deposit_category: get_env('deposit_category', DEFAULT_DEPOSIT_CATEGORY),
              test_mode: get_env('test_mode')
            }
          )

          raise Exception.new(ERROR_SECRET_REQUIRED) if _settings.secret.blank?
          raise Exception.new(ERROR_KEY_REQUIRED) if _settings.key.blank?
          raise Exception.new(ERROR_DES_KEY_REQUIRED) if _settings.des_key.blank?

          _settings
        end
      end

      def sign(params)
        options = params.dup.symbolize_keys.merge(
          key: settings.key,
          ts: Time.now.to_i
        ).compact.sort_by(&:first).to_h

        # line = options.map { |(k, v)|
        #   "#{k}:#{v}"
        # }.concat([settings.secret])

        line = %I[
          type
          amount
          account_id
          currency
          url_user_on_success
          url_user_on_fail
          url_api_on_success
          url_api_on_fail
          no_expiration
          deposit_category
          key
          ts
        ]
        .select { |k| options[k].present? }
        .map { |k| "#{k}:#{options[k]}" }
        .concat([settings.secret])

        line = line.join(':')

        options[:sign] = Digest::MD5.hexdigest(line)

        options
      end

      def get_env(key, default = nil)
        ENV.fetch("#{ENV_NAMESPACE}_#{key.upcase}", default)
      end
    end
  end

end