Openfigi php request -> Request body must be a JSON array - php

Question

I am trying to use the openfigi api with php. I keep getting this error message: "Request body must be a JSON array.". Any ideas on how to solve this? I have tried several solutions.
$curlUrl = 'https://api.openfigi.com/v2/mapping';
$data = array('idType' => 'ID_WERTPAPIER', 'idValue' => '851399', 'exchCode' => 'US');
$j = json_encode($data);
//$apiToken = 'X-OPENFIGI-APIKEY: xxx';
$httpHeadersArray = Array();
$httpHeadersArray[] = 'Content-Type: application/json';
//$httpHeadersArray[] = $apiToken;
//open connection
$ch = curl_init();
//set the url, number of POST vars, POST data
curl_setopt($ch, CURLOPT_URL, $curlUrl);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt($ch, CURLOPT_POSTFIELDS, $j);
curl_setopt($ch, CURLOPT_HTTPHEADER, $httpHeadersArray);
$res = curl_exec($ch);
echo "<pre>";
print_r($res);
echo "</pre>";

Answer 1

had the same problem, but solved it.
This is my working code:
// The url you wish to send the POST request to
$url = 'https://api.openfigi.com/v2/mapping/';
// Create a new cURL resource
$ch = curl_init($url);
// The data to send to the API
$postData = array(
array(
"idType" => "ID_ISIN",
"idValue" => "US4592001014"
)
);
// Setup cURL
curl_setopt_array($ch, array(
CURLOPT_POST => TRUE,
CURLOPT_RETURNTRANSFER => TRUE,
CURLOPT_POSTFIELDS => json_encode($postData)
));
curl_setopt( $ch, CURLOPT_HTTPHEADER, array('Content-Type:application/json'));
print_r(json_encode($postData));
// Send the request
$response = curl_exec($ch);
// Check for errors
if($response === FALSE){
die(curl_error($ch));
}
// Decode the response
$responseData = json_decode($response, TRUE);
// Print the date from the response
print_r($responseData);