Implement Curl::setError() and MultiCurl::setError()

examples/curl_set_error.php

@@ -0,0 +1,44 @@
+<?php
+
+require __DIR__ . '/../vendor/autoload.php';
+
+use Curl\Curl;
+
+$max_retries = 5;
+
+$curl = new Curl();
+$curl->setRetry($max_retries);
+
+$curl->beforeSend(function ($instance) {
+    echo 'about to make request to ' . $instance->url . "\n";
+});
+
+$curl->error(function ($instance) {
+    echo 'not lucky this round' . "\n";
+});
+
+$curl->success(function ($instance) {
+    echo
+        'success!' . "\n" .
+        'got number ' . $instance->response->args->number . ' ' .
+        'after ' . $instance->attempts . ' attempt(s).' . "\n";
+});
+
+$curl->setError(function ($instance) {
+    $random_number = (int)$instance->response->args->number;
+    $lucky = $random_number === 7;
+    $instance->error = !$lucky;
+
+    if (!$lucky) {
+        $instance->setUrl('https://httpbin.org/get?number=' . random_int(0, 10));
+    }
+});
+
+$curl->get('https://httpbin.org/get?number=' . random_int(0, 10));
+
+// $ php curl_set_error.php
+// about to make request to https://httpbin.org/get?number=3
+// about to make request to https://httpbin.org/get?number=1
+// about to make request to https://httpbin.org/get?number=7
+// success!
+// got number 7 after 3 attempt(s).