Sending voip push notification from one signal triggered firebase cloud functions - swift

Question

I`m trying to send Voip push notification from one signal triggered by firebase cloud functions. So far it being able to send normal message push notifications from one signal to IOS devices using firebase cloud functions with below code.
var sendNotification = function(data) {
var headers = {
"Content-Type": "application/json; charset=utf-8"
};
var options = {
host: "onesignal.com",
port: 443,
path: "/api/v1/notifications",
method: "POST",
headers: headers
};
var https = require('https');
var req = https.request(options, function(res) {
res.on('data', function(data) {
console.log("Response:");
console.log(JSON.parse(data));
});
});
req.on('error', function(e) {
console.log("ERROR:");
console.log(e);
});
req.write(JSON.stringify(data));
req.end();
};
var message = {
app_id: "*********************",
contents: {"en": "English Message"},
include_player_ids: ["******************7b0bdc38"]
};
sendNotification(message);
Does anyone know how to send Voip push notifications from one signal using firebase cloud functions??
(If the above code is required to change some part of it, it would be very thankful telling me where it is.)

Answer 1

As per one signal documentation (https://documentation.onesignal.com/docs/voip-notifications) you are missing the DEVICE_VOIP_TOKEN that you should have received from the iOS application.
Please try adding that and let me know, think of adding the exact error message if any.