I am using a slightly modified version of http://code.google.com/p/rolling-curl/
My question is similar to this: http://code.google.com/p/rolling-curl/issues/detail?id=25
Basically, I am doing a bunch of requests, once I find the one I want, all other pending requests should be terminated from the queue and any running CURL handles should be removed from memory, even if they aren't done downloading yet.
Code here:
<?php
/*
Authored by Josh Fraser (www.joshfraser.com)
Released under Apache License 2.0
Maintained by Alexander Makarov, http://rmcreative.ru/
$Id$
*/
/**
* Class that represent a single curl request
*/
class RollingCurlRequest {
public $url = false;
public $method = 'GET';
public $post_data = null;
public $headers = null;
public $options = null;
public $extras = null;
/**
* @param string $url
* @param string $method
* @param $post_data
* @param $headers
* @param $options
* @return void
*/
function __construct($url, $method = "GET", $post_data = null, $headers = null, $options = null, $extras = null) {
$this->url = $url;
$this->method = $method;
$this->post_data = $post_data;
$this->headers = $headers;
$this->options = $options;
$this->extras = $extras;
}
/**
* @return void
*/
public function __destruct() {
unset($this->url, $this->method, $this->post_data, $this->headers, $this->options);
}
}
/**
* RollingCurl custom exception
*/
class RollingCurlException extends Exception {
}
/**
* Class that holds a rolling queue of curl requests.
*
* @throws RollingCurlException
*/
class RollingCurl {
/**
* @var int
*
* Window size is the max number of simultaneous connections allowed.
*
* REMEMBER TO RESPECT THE SERVERS:
* Sending too many requests at one time can easily be perceived
* as a DOS attack. Increase this window_size if you are making requests
* to multiple servers or have permission from the receving server admins.
*/
private $window_size = 5;
/**
* @var float
*
* Timeout is the timeout used for curl_multi_select.
*/
private $timeout = 10;
/**
* @var string|array
*
* Callback function to be applied to each result.
*/
private $callback;
/**
* @var array
*
* Set your base options that you want to be used with EVERY request.
*/
protected $options = array(
CURLOPT_SSL_VERIFYPEER => 0,
CURLOPT_RETURNTRANSFER => 1,
CURLOPT_CONNECTTIMEOUT => 30,
CURLOPT_TIMEOUT => 30,
CURLOPT_ENCODING => "gzip"
);
/**
* @var array
*/
private $headers = array();
/**
* @var Request[]
*
* The request queue
*/
private $requests = array();
/**
* @var RequestMap[]
*
* Maps handles to request indexes
*/
public $requestMap = array();
/**
* @param $callback
* Callback function to be applied to each result.
*
* Can be specified as 'my_callback_function'
* or array($object, 'my_callback_method').
*
* Function should take three parameters: $response, $info, $request.
* $response is response body, $info is additional curl info.
* $request is the original request
*
* @return void
*/
function __construct($callback = null) {
$this->callback = $callback;
}
/**
* @param string $name
* @return mixed
*/
public function __get($name) {
return (isset($this->{$name})) ? $this->{$name} : null;
}
/**
* @param string $name
* @param mixed $value
* @return bool
*/
public function __set($name, $value) {
// append the base options & headers
if ($name == "options" || $name == "headers") {
$this->{$name} = $value + $this->{$name};
} else {
$this->{$name} = $value;
}
return true;
}
/**
* Add a request to the request queue
*
* @param Request $request
* @return bool
*/
public function add($request) {
$this->requests[] = $request;
return true;
}
/**
* Create new Request and add it to the request queue
*
* @param string $url
* @param string $method
* @param $post_data
* @param $headers
* @param $options
* @return bool
*/
public function request($url, $method = "GET", $post_data = null, $headers = null, $options = null) {
$this->requests[] = new RollingCurlRequest($url, $method, $post_data, $headers, $options);
return true;
}
/**
* Perform GET request
*
* @param string $url
* @param $headers
* @param $options
* @return bool
*/
public function get($url, $headers = null, $options = null) {
return $this->request($url, "GET", null, $headers, $options);
}
/**
* Perform POST request
*
* @param string $url
* @param $post_data
* @param $headers
* @param $options
* @return bool
*/
public function post($url, $post_data = null, $headers = null, $options = null) {
return $this->request($url, "POST", $post_data, $headers, $options);
}
/**
* Execute processing
*
* @param int $window_size Max number of simultaneous connections
* @return string|bool
*/
public function execute($window_size = null) {
// rolling curl window must always be greater than 1
if (sizeof($this->requests) == 1) {
return $this->single_curl();
} else {
// start the rolling curl. window_size is the max number of simultaneous connections
return $this->rolling_curl($window_size);
}
}
/**
* Performs a single curl request
*
* @access private
* @return string
*/
private function single_curl() {
$ch = curl_init();
$request = array_shift($this->requests);
$options = $this->get_options($request);
curl_setopt_array($ch, $options);
$output = curl_exec($ch);
$info = curl_getinfo($ch);
// it's not neccesary to set a callback for one-off requests
if ($this->callback) {
$callback = $this->callback;
if (is_callable($this->callback)) {
call_user_func($callback, $output, $info, $request);
}
}
else
return $output;
return true;
}
/**
* Performs multiple curl requests
*
* @access private
* @throws RollingCurlException
* @param int $window_size Max number of simultaneous connections
* @return bool
*/
private function rolling_curl($window_size = null) {
if ($window_size)
$this->window_size = $window_size;
// make sure the rolling window isn't greater than the # of urls
if (sizeof($this->requests) < $this->window_size)
$this->window_size = sizeof($this->requests);
if ($this->window_size < 2) {
throw new RollingCurlException("Window size must be greater than 1");
}
$master = curl_multi_init();
// start the first batch of requests
for ($i = 0; $i < $this->window_size; $i++) {
$ch = curl_init();
$options = $this->get_options($this->requests[$i]);
curl_setopt_array($ch, $options);
curl_multi_add_handle($master, $ch);
// Add to our request Maps
$key = (string) $ch;
$this->requestMap[$key] = $i;
}
do {
while (($execrun = curl_multi_exec($master, $running)) == CURLM_CALL_MULTI_PERFORM) ;
if ($execrun != CURLM_OK)
break;
// a request was just completed -- find out which one
while ($done = curl_multi_info_read($master)) {
// get the info and content returned on the request
$info = curl_getinfo($done['handle']);
$output = curl_multi_getcontent($done['handle']);
// send the return values to the callback function.
$callback = $this->callback;
if (is_callable($callback)) {
$key = (string) $done['handle'];
$request = $this->requests[$this->requestMap[$key]];
unset($this->requestMap[$key]);
call_user_func($callback, $output, $info, $request);
}
// start a new request (it's important to do this before removing the old one)
if ($i < sizeof($this->requests) && isset($this->requests[$i]) && $i < count($this->requests)) {
$ch = curl_init();
$options = $this->get_options($this->requests[$i]);
curl_setopt_array($ch, $options);
curl_multi_add_handle($master, $ch);
// Add to our request Maps
$key = (string) $ch;
$this->requestMap[$key] = $i;
$i++;
}
// remove the curl handle that just completed
curl_multi_remove_handle($master, $done['handle']);
}
// Block for data in / output; error handling is done by curl_multi_exec
if ($running)
curl_multi_select($master, $this->timeout);
} while ($running);
curl_multi_close($master);
return true;
}
/**
* Helper function to set up a new request by setting the appropriate options
*
* @access private
* @param Request $request
* @return array
*/
private function get_options($request) {
// options for this entire curl object
$options = $this->__get('options');
if (ini_get('safe_mode') == 'Off' || !ini_get('safe_mode')) {
$options[CURLOPT_FOLLOWLOCATION] = 1;
$options[CURLOPT_MAXREDIRS] = 5;
}
$headers = $this->__get('headers');
// append custom options for this specific request
if ($request->options) {
$options = $request->options + $options;
}
// set the request URL
$options[CURLOPT_URL] = $request->url;
// posting data w/ this request?
if ($request->post_data) {
$options[CURLOPT_POST] = 1;
$options[CURLOPT_POSTFIELDS] = $request->post_data;
}
if ($headers) {
$options[CURLOPT_HEADER] = 0;
$options[CURLOPT_HTTPHEADER] = $headers;
}
return $options;
}
/**
* @return void
*/
public function __destruct() {
unset($this->window_size, $this->callback, $this->options, $this->headers, $this->requests);
}
}
Edit: On second thought, there should be 2 functions:
1) Delete any requests in the queue and unset any curl resources from memory without finishing.
2) Delete any requests in queue and while until all curl resources are finished.
I will probably contribute the functions/code/suggestions I get here into the project with credit to author of the selected answer.