Dear Experts...
I have never came across or needed this.
Now I do....

I usually upload CSV files to a cellular provider in my countery via an app I made that formulate notifications to clients.
That supplier has an API, and I cannot send anything unless one pays for a package, but if DOES HAVE A SANDBOX MODE.
It also supplies these odd things i know nothing of : SWAGGER and POSTMAN.
Now smart people, how do you go from zero to sending a message with an API?
They gave this Schema :
{
"communication": {
"receiver": [
{
"phoneNumber": "27789078941"
}
],
"sender": {
"phoneNumber": "27789078942",
"name": "VideoPlay"
},
"deliveryReceiptFlag": false,
"receiptCallbackUrl": "http://host.com",
"callbackNotifyUrl": "http://host.com",
"description": "This is communication message for promotion",
"type": "sms",
"sourceTransactionId": "123e4567-e89b-42d3-a456-556642440000",
"content": "This is a Promotion Message ",
"sendTime": "2017-07-22T16:28:55.444000",
"bindExists": true
}
}
Small steps please. I am completely lost.

-Peter