Overview of Facebook Account Kit API
- Facebook Account Kit allows you to securely authenticate users by their phone number without requiring the need for a password. It offers a smooth user experience while also maintaining security.
- It supports both SMS and voice calls for OTP (One-Time Passcode) delivery, widening user accessibility.
Integrating Account Kit with PHP
- First, ensure you have the Account Kit JavaScript SDK integrated on your client-side. This SDK will handle the user interaction and provide a code that you will exchange for account information server-side.
- Once the user successfully enters their phone number and verification code, Account Kit returns an authorization code to your client-side application. This will be sent to your server to authenticate the user.
Exchanging Code for Access Token
- Receive the authorization code from the front-end and prepare to exchange it for a user access token. The exchange happens on your PHP backend to maintain security and keep your app secret secure.
- Use PHP's `file_get_contents()` or `cURL` to make a request to the Account Kit server.
$app_id = '{your-app-id}';
$app_secret = '{your-app-secret}';
$version = 'v1.3'; // API version
$auth_code = $_POST['auth_code'];
$token_exchange_url = 'https://graph.accountkit.com/'.$version.'/access_token?grant_type=authorization_code'
. '&code='.$auth_code
. "&access_token=AA|$app_id|$app_secret";
$response = file_get_contents($token_exchange_url);
$data = json_decode($response, true);
if (isset($data['access_token'])) {
$access_token = $data['access_token'];
// Continue to next step using $access_token
}
Retrieving User Information
- Once you have the user access token, you can now retrieve the user's phone number details. You'll query the Account Kit API again using the access token.
- Make another API call to get account information like the phone number associated with the user account.
$user_info_url = 'https://graph.accountkit.com/'.$version.'/me'
. '?access_token='.$access_token;
$user_info_response = file_get_contents($user_info_url);
$user_data = json_decode($user_info_response, true);
if (isset($user_data['phone'])) {
$phone_number = $user_data['phone']['number'];
// Use the phone number as needed in your application
}
Best Practices
- Always handle errors gracefully. Check for error messages in the response you get from the Account Kit API and act accordingly.
- Ensure that you store the received user information securely, especially if you're storing sensitive data like phone numbers.
- Verify that all responses and interactions with Account Kit occur over HTTPS, both from the client-side and server-side, to maintain security.
Handling Edge Cases
- Consider implementing a retry mechanism for network requests in case of temporary failures.
- Have a plan for gracefully handling scenarios where the API limits are reached or where Facebook might change its API in future versions.
This approach will effectively set up phone number authentication using the Facebook Account Kit in a PHP application, providing secure and user-friendly access.
