curl_multi_add_handle - PHP code example

How to Use the PHP Function Curl_Multi_Add_Handle()

Article By: khushi

The PHP cURL library is a popular extension that allows web developers to retrieve data from various websites quickly & securely. It’s often used to interact with APIs & other external services, but can also be helpful for retrieving data from user interfaces & other sources. This library can be especially useful if you’re working with complex applications that need to send multiple requests over different protocols.

To use the cURL library in your PHP application, you need to initialize it using the curl_init() function. This function returns a cURL session that you can then configure with various options using the curl_setopt() functions. These options can include the URL to request, the request method, headers & more. Once you’ve configured the cURL session, you can then call the curl_exec() function to execute the request. This will return the response as a string that can then be processed in your PHP application.

One of the more advanced uses for the cURL library is to multiplex requests & run them in parallel. To do this you need to create an array of cURL handles, add them to the multi handle and then process them in parallel. The curl_multi_add_handle() function will allow you to do this. It takes a list of indexed arrays of URLs or arrays of cURL handles and will do them in parallel, ensuring that the whole batch is only as slow as the slowest request.

curl_multi_add_handle example

                $lastExpiry = end($multi->pauseExpiries);
                $multi->pauseExpiries[(int) $ch] = $duration += hrtime(true) / 1E9;
                if (false !== $lastExpiry && $lastExpiry > $duration) {
                    asort($multi->pauseExpiries);
                }
                curl_pause($ch, \CURLPAUSE_ALL);
            } else {
                unset($multi->pauseExpiries[(int) $ch]);
                curl_pause($ch, \CURLPAUSE_CONT);
                curl_multi_add_handle($multi->handle, $ch);
            }
        };

        $this->inflate = !isset($options['normalized_headers']['accept-encoding']);
        curl_pause($ch, \CURLPAUSE_CONT);

        if ($onProgress = $options['on_progress']) {
            $url = isset($info['url']) ? ['url' => $info['url']] : [];
            curl_setopt($ch, \CURLOPT_NOPROGRESS, false);
            curl_setopt($ch, \CURLOPT_PROGRESSFUNCTION, static function D$ch, $dlSize, $dlNow) use ($onProgress, &$info, $url, $multi, $debugBuffer) {
                try {

/** * Ticks the curl event loop. */
    public function tick(): void
    {
        // Add any delayed handles if needed.         if ($this->delays) {
            $currentTime = Utils::currentTime();
            foreach ($this->delays as $id => $delay) {
                if ($currentTime >= $delay) {
                    unset($this->delays[$id]);
                    \curl_multi_add_handle(
                        $this->_mh,
                        $this->handles[$id]['easy']->handle
                    );
                }
            }
        }

        // Step through the task queue which may add additional requests.         P\Utils::queue()->run();

        if ($this->active && \curl_multi_select($this->_mh, $this->selectTimeout) === -1) {

        $multihandle = curl_multi_init();
        $subrequests = [];
        $subhandles  = [];

        $class = get_class($this);
        foreach ($requests as $id => $request) {
            $subrequests[$id] = new $class();
            $subhandles[$id]  = $subrequests[$id]->get_subrequest_handle($request['url'], $request['headers'], $request['data'], $request['options']);
            $request['options']['hooks']->dispatch('curl.before_multi_add', [&$subhandles[$id]]);
            curl_multi_add_handle($multihandle, $subhandles[$id]);
        }

        $completed       = 0;
        $responses       = [];
        $subrequestcount = count($subrequests);

        $request['options']['hooks']->dispatch('curl.before_multi_exec', [&$multihandle]);

        do {
            $active = 0;