Converting wp_remote_post() to cURL - php

Question

I have this WordPress code using wp_remote_post() to make an API call to LinkedIn.
$args = array(
'headers' => array('Content-Type' => 'text/xml'),
'body' => "<?xml version='1.0' encoding='UTF-8' standalone='yes'?><company><id>{$nCompanyID}</id></company>"
);
$access_token = $datapass->access_token_get();
$params = array('oauth2_access_token' => $access_token);
$resource = "https://api.linkedin.com/v1/people/~/following/companies?" . http_build_query($params);
$response = wp_remote_post( $resource, $args);
$code = $response['response']['code'];
$body = wp_remote_retrieve_body($response);
$RV = ($code == '201');
return $RV;
It works. Now, I need to convert it to php cURL.
I have tried various examples of php cURL posting XML that I found online, but no luck.
Here's the latest attempt.
$access_token = "long_string_of_characters";
$nCompanyID = 2495437;
$xml = "<?xml version='1.0' encoding='UTF-8' standalone='yes'?><company><id>{$nCompanyID}</id></company>";
$url = 'https://api.linkedin.com/v1/people/~/following/companies?oauth2_access_token='.$access_token;
$headers = array(
"Content-type: text/xml",
"Content-length: " . strlen($xml)
);
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, array('body' => $xml));
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
$data = curl_exec($ch);
$data comes back with a 400 error and message saying 'Unexpected element: CDATA'. If I remove the array from CURLOPT_POSTFIELDS and use just $xml, $data comes back as an empty string.
Any help will be appreciated.

Answer 1

If the server is expecting an XML POST, then passing an array to CURLOPT_POSTFIELDS is not going to make it happy.
Note in your original code the method of building the URL:
$params = array('oauth2_access_token' => $access_token);
$resource = "https://api.linkedin.com/v1/people/~/following/companies?" . http_build_query($params);
You'll want to keep that. http_build_query() performs the escaping needed if your access token contains special characters.
I'd have questions whether or not your access token is valid, given the original code seems to dynamically generate it with $datapass->access_token_get();
Otherwise it looks like you have everything set the same.
<?php
$access_token = "long_string_of_characters";
$nCompanyID = 2495437;
$xml = "<?xml version='1.0' encoding='UTF-8' standalone='yes'?><company><id>$nCompanyID</id></company>";
$params = ["oauth2_access_token" => $access_token];
$url = "https://api.linkedin.com/v1/people/~/following/companies?";
$url .= http_build_query($params);
$headers = [
"Content-type: text/xml",
"Content-length: " . strlen($xml)
];
$ch = curl_init();
curl_setopt_array($ch, [
CURLOPT_URL => $url,
CURLOPT_RETURNTRANSFER => true,
CURLOPT_POST => true,
CURLOPT_POSTFIELDS => $xml,
CURLOPT_HTTPHEADER => $headers,
]);
$data = curl_exec($ch);