How to make a POST request with PHP given the following HTTP + JSON

Question

I've been trying to make a POST request with PHP with something called the WorkWave API. This is the code they provide for making a POST request to set the app's callback URL:

POST /api/v1/callback HTTP/1.0
Accept: application/json
X-WorkWave-Key: YOUR API KEY
Host: wwrm.workwave.com
Content-Type: application/json

{
  "url": "https://my.server.com/new-callback",
  "signaturePassword": "g394g732vhsdfiv34",
  "test": true
}

I'm pretty new to processing POST and GET requests, so I don't really understand what's going on here. What exactly is the blob of keys & values above the JSON brackets? How do I translate what is given here to PHP and what are the most important things to understand when doing so?

Solution

The first blob are the headers that you need to send with your request. The JSON is the post body payload.

<?php

$url = 'https://wwrm.workwave.com/api/v1/callback';

$data = '
{
  "url": "https://my.server.com/new-callback",
  "signaturePassword": "g394g732vhsdfiv34",
  "test": true
}
';

$additional_headers = array(                                                                          
   'Accept: application/json',
   'X-WorkWave-Key: YOUR API KEY',
   'Host: wwrm.workwave.com',
   'Content-Type: application/json'
);

$ch = curl_init($url);                                                                      
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");                                                                     
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);                                                                  
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);                                                                      
curl_setopt($ch, CURLOPT_HTTPHEADER, $additional_headers); 

$server_output = curl_exec ($ch);

echo  $server_output;