Mobile Number Verification Using 2FACTOR in Rails Application

Here we will be using 2FACTOR authentication API to send OTP from Rails application. With free trial account you will get 100 OTP SMA balance. Follow below steps to get started!

Create a new 2FACTOR account

Visit 2FACTOR portal and create your free trial account using your email address and phone number. A unique API key will be generated for your account. You can get this API key in Manage Account > Account Summary section on home page. This API key will be used to call 2FACTOR API’s.

We will be using Net::HTTP to call 2FACTOR API’s.

Create Service class to make API request to 2FACTOR portal from your application.

Create a new file two_factor.rb in app/services/mobile_verification directory and add below code in the two_factor.rb file.
Don’t forget to replace API_KEY. Add API_KEY in environment file for security.

module MobileVerification
  class TwoFactor
    BASE_URL = 'http://2factor.in/API/V1'
    API_KEY = 'Your APi Key here'
    class << self
      def send_otp(opts: {})
        uri = "#{vendor_base_url}/SMS/#{opts[:mobile_number]}/AUTOGEN"
        url = URI(uri)
        send_request(url)
      end
      def verify_otp(opts: {})
        url = URI("#{vendor_base_url}/SMS/VERIFY/#{opts[:session_id]}/#{opts[:otp]}")
        send_request(url)
      end
      private
      def send_request(url)
        http = Net::HTTP.new(url.host, url.port)
        request = Net::HTTP::Get.new(url)
        request["content-type"] = 'application/x-www-form-urlencoded'
        response = http.request(request)
      rescue => e
        render_errors(e.message)
      else
        render_response(response)
      end
      def render_response(response)
        body = JSON.parse(response.read_body)
        if body['Status'] == 'Error' || (body['Status'] == 'Success' && body['Details'] == 'OTP Expired')
          render_errors(body['Details'])
        else
          render_success(body['Details'])
        end
      end
      def render_errors(details)
        { success: false, details: details }
      end
      def render_success(details)
        { success: true, details: details }
      end
      def vendor_base_url
        BASE_URL + '/' + API_KEY
      end
    end
  end
end

Create API endpoints to send and verify OTP.
Add a new controller method to send and verify OTP in MobileVerificationsController as below:

module Api
  module V1
    class MobileVerificationsController < ApiController
      def send_otp
        mobile_number = params.dig(:mobile_verification, :mobile_number)
        if mobile_number.present?
          response = MobileVerification::TwoFactor.send_otp(
            opts: {
              mobile_number: mobile_number
            }
          )
          if response[:success]
            render json: response, status: :ok
          else
            render_unprocessable_entity('Failed to send OTP')
          end
        else
          render_unprocessable_entity('mobile number is missing')
        end
      end
      def verify_otp
        session_id = params.dig(:mobile_verification, :session_id)
        otp = params.dig(:mobile_verification, :otp)
        if session_id && otp
          response = MobileVerification::TwoFactor(
            opts: {
              session_id: session_id,
              otp: otp
            }
          )
          if response[:success]
            render json: response, status: :ok
          else
            render_unprocessable_entity('Failed to verify OTP')
          end
        else
          render_unprocessable_entity('session_id or otp is missing')
        end
      end
      private
      def render_unprocessable_entity(message = nil)
        render json: { message: message }, status:   :unprocessable_entity
      end
    end
  end
end

By default 2FACTOR will generate 6 digits OTP. There are many customization available. Reference for the API documentation is here 2factor-api-docs.

You will get below response back after sending OTP:

{
  "Status": "Success",
  "Details": "ff9ab5b0-452e-11e7-94da-0200cd936042"
}

And verify OTP will get below response:

{
  "Status": "Success",
  "Details": "OTP Matched"
}

session_id refers to the ‘Details’ field value returned by the SEND OTP Endpoints. In this case value ff9ab5b0–452e-11e7–94da-0200cd936042 corresponding to Details field is referred to as session_id.

In the verify_otp method you can also perform your custom actions like setting users mobile verified true or same service can be used for user authentication and setting current user in application controller, creating JWT after verifying OTP.

Thats it! Now you can start sending SMS OTP’s from your application.