REST API service: how to call it correctly via PHP curl?

Question

Let's say I have a running service API that responds to a url like:

http://example.com/param/1

It's served on both get and post verbs. Param=1 is the param considered

How should I perform correctly a curl request to pass the parameter (POST)?

If i browse: http://example.com/param/1 I'll have back the expected response (GET)

But if I do the following, it is not going to work:

$service_url = 'http://example.com/';
$curl = curl_init($service_url);
$curl_post_data = array('param'=>1);

curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl, CURLOPT_POST, true);
curl_setopt($curl, CURLOPT_POSTFIELDS, $curl_post_data);
$curl_response = curl_exec($curl);
if ($curl_response === false) {
    $info = curl_getinfo($curl);
    curl_close($curl);
    die('error occured during curl exec. Additional info: ' . var_export($info));
}
curl_close($curl);
$decoded = json_decode($curl_response);
if (isset($decoded->response->status) && $decoded->response->status == 'ERROR') {
    die('error occured: ' . $decoded->response->errormessage);
}
echo 'response ok!';
var_export($decoded->response);

Even changing it like the folowing won't work:

$service_url = 'http://example.com/param/1';
$curl = curl_init($service_url);

curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl, CURLOPT_POST, true);
$curl_response = curl_exec($curl);
if ($curl_response === false) {
    $info = curl_getinfo($curl);
    curl_close($curl);
    die('error occured during curl exec. Additional info: ' . var_export($info));
}
curl_close($curl);
$decoded = json_decode($curl_response);
if (isset($decoded->response->status) && $decoded->response->status == 'ERROR') {
    die('error occured: ' . $decoded->response->errormessage);
}
echo 'response ok!';
var_export($decoded->response);

This instead works: but i guess it still will be a GET

$service_url = 'http://example.com/param/1';
$curl = curl_init($service_url);
$curl_response = curl_exec($curl);
if ($curl_response === false) {
    $info = curl_getinfo($curl);
    curl_close($curl);
    die('error occured during curl exec. Additional info: ' . var_export($info));
}
curl_close($curl);
$decoded = json_decode($curl_response);
if (isset($decoded->response->status) && $decoded->response->status == 'ERROR') {
    die('error occured: ' . $decoded->response->errormessage);
}
echo 'response ok!';
var_export($decoded->response);

Answer 1

$service_url = 'http://example.com/param/1';     
$ch = curl_init($service_url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, "param1=value1&param2=value2&..");
$response = curl_exec($ch);
curl_close($ch);