Building a JWT for Twilio's Authy using Apps Script - google-apps-script

Question

The No-PII user registration JWT for adding a user in Twilio's authy requires us to build a JWT from scratch.
I tried looking everywhere on how to get a JWT created using Google Apps Script but wasn't to find the right way to make that happen. It specifically needs to be of HS256 alg.
I require the final payload to look exactly like this -
// Example Payload
{
"iss": "My Authy App",
"iat": 1554395479,
"exp": 1554395879,
"context": {
"custom_user_id": "3YgAIZklGPHmwpJfIC0PDy0E7l763OF3BHZo1p2xKhY",
"authy_app_id": "1111111"
}
}
// Example Header
{
"alg": "HS256",
"typ": "JWT"
}
Can someone please help me with this or perhaps point me to an appropriate article/documentation for this??

Answer 1

The general syntax for URL fetch with Google Apps Script is the following:
var body={
"iss": "My Authy App",
"iat": 1554395479,
"exp": 1554395879,
"context": {
"custom_user_id": "3YgAIZklGPHmwpJfIC0PDy0E7l763OF3BHZo1p2xKhY",
"authy_app_id": "1111111"
};
var header={
"alg": "HS256",
"typ": "JWT"
};
var url='YOUR URL';
var options={
method: 'POST',
headers: header,
muteHttpExceptions: true,
contentType: 'application/json',
payload: JSON.stringify(body)
};
var response=UrlFetchApp.fetch(url, options);
According to the documentation link you provided, you might need to provide an API key. In this case, you URL should be something like var url=basicURL+"apikey="+XXX
I do not have a Twilio account to test it, but the sample provided above is the general procedure for Apps Script and you can find more references under the following links:
Working with Third-Party APIs
External APIs
Twilio Send a SMS message
Note that in the latter sample the payload is not in quotes.