What are some troubleshooting steps to consider when encountering issues with cURL requests in PHP, such as not receiving expected results or error messages?

Issue: When encountering issues with cURL requests in PHP, such as not receiving expected results or error messages, it could be due to incorrect URL formatting, missing headers, or server-side issues. To troubleshoot, check the URL being used, ensure necessary headers are included, and verify the server is properly responding to the request.

// Example cURL request with proper URL formatting and headers
$url = 'https://api.example.com/data';
$ch = curl_init($url);

// Set necessary headers
$headers = [
    'Content-Type: application/json',
    'Authorization: Bearer YOUR_ACCESS_TOKEN'
];
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

// Execute the cURL request
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);

// Check for errors
if($response === false) {
    echo 'cURL error: ' . curl_error($ch);
} else {
    echo 'Response: ' . $response;
}

// Close cURL session
curl_close($ch);