Add a callback closure to a class constructor - php

Question

I have a class that someone else wrote. It does a lot of things for me, and one thing it does for me is it makes requests to an external service.
public function makeRequest() {
...bunch of curl stuff here
}
So what I wanted to do is modify the constructor of the class so that I could pass in a function, and the function could get called after the curl stuff. I come from a javascript background so I'm definitely doing this the wrong way, but this is what I did:
private $requestLogger;
public function __construct(...other variables, $requestLogger = null) {
if ($requestLogger) {
$this->requestLogger = $requestLogger;
}
}
public function makeRequest() {
...bunch of curl stuff here
if ($this->requestLogger) {
$curlInfo = curl_getinfo($ch);
$this->requestLogger($curlInfo['url'], $curlInfo['http_code'], $request, $response);
}
}
And that when when I make a new instance, I can do it like this
$client = new ApiClient(..., function($url, $responseCode, $requestText, $responseText){
// do whatever i want here
});
However, this hasn't worked. I get this message: 500: Call to undefined method ApiClient::requestLogger()
How do I set myself up to pass a callback function to this class?

Answer 1

When you do: $this->requestLogger(...), PHP thinks you're trying to call a class method called requestLogger().
If you want to call a function in a class property, you can use call_user_func_array(). Something like this:
call_user_func_array($this->requestLogger, [
$curlInfo['url'],
$curlInfo['http_code'],
$request,
$response
]);
A tip, before trying to call it, make sure it contains something that's callable and not just empty:
if (is_callable($this->requestLogger)) {
call_user_func_array(...);
}