SMS Phone Verification in Go

This is a small Go app that shows how to perform SMS phone verification.

Find out more on Twilio Code Exchange.

Application Overview

It uses Twilio Verify to verify phone numbers and add an additional layer of security, helping prevent fraudulent users from registering with your business.

It steps users through the process of creating an account on a (fictional) website; specifically:

1. The user needs to enter a username, password, and phone number in the initial step and submit the form.
2. Then, the customer is sent an SMS with a verification code for 2-Factor Authentication (2FA), and redirected to the second step in the process where they will be asked to enter a verification code into the webpage to verify their account.
3. The verification code is then validated against the Twilio Verify service. If the code is valid, the user is then redirected to the logged in page, indicating that they have successfully registered with the application. If the code is not valid, the user is redirected back to the verify step, where an error is displayed, showing that verification failed.

Requirements

To use the application, you'll need the following:

• Go 1.22 or above
• A Twilio account (free or paid) with a phone number. Click here to create one, if you don't have one.
• A phone number that can received SMS
• Your web browser of choice

Getting Started

After cloning the code to where you store your Go projects, and change into the project directory. Then, copy .env.example as .env, by running the following command:

cp -v .env.example .env

After that, set values for TWILIO_ACCOUNT_SID, TWILIO_AUTH_TOKEN, TWILIO_PHONE_NUMBER. You can retrieve these details from the Account Info panel of your Twilio Console dashboard.

Create a Verify Service

Following that, create a Verify V2 service.

First, open the Twilio Console in your browser of choice and navigate to Explore products > Verify > Services. There, click Create new.

In the Create new (Verify Service) form that appears, provide a Friendly name, enable the SMS verification channel, and click Continue.

Following that, click Continue in the Enable Fraud Guard stage.

Now, you'll be on the Service settings page for your new Verify Service. Copy the Service SID and set it as the value of TWILIO_VERIFICATION_SID in .env.

Launch the Application

When that's done, run the following command to start the application:

go run main.go

With the application ready to go, open http://localhost:8000 in your browser of choice. There, you'll see the form where you can request a verification code.

Enter your username, password, and phone number and submit the form. Then, you'll see a form which you can validate the verification code.

Enter the verification code that you should have received via SMS and submit the form. You will now be "authenticated" with the application, and on the logged in page.

There is no explicit log out functionality. To do that, you'll have to clear the cookies for localhost using your browser's settings tooling.

Contributing

If you want to contribute to the project, whether you have found issues with it or just want to improve it, here's how:

• Issues: ask questions and submit your feature requests, bug reports, etc
• Pull requests: send your improvements

Resources

Find out more about the project on CodeExchange.

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• Add a GitHub Star to the project
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