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How to use phpcurl to implement multi-process download file classes
- jackloveOriginal
- 2018-06-08 16:55:332644browse
Batch download files generally use a loop method to download files one by one. However, if bandwidth and server performance permit, using multiple processes for downloading can greatly improve downloading efficiency. This article introduces PHP's multi-process request method using curl to achieve simultaneous downloading of files by multiple processes.
Principle:
Use curl's batch processing method to open multiple processes to download files in batches.
Main method:
curl_multi_init
Return a new cURL batch handle
curl_multi_add_handle
Add a separate curl handle to the curl batch session
curl_multi_exec
Run the current cURL handle Sub-connection
curl_multi_getcontent
If CURLOPT_RETURNTRANSFER is set, returns the text stream of the obtained output
curl_multi_remove_handle
Remove a handle resource in the curl batch handle resource
curl_multi_close
Close a group of cURL handles
The complete code is as follows:
BatchDownLoad.class.php
<?php/**
* 多进程批量下载文件（使用php curl_multi_exec实现）
* Date: 2017-07-16
* Author: fdipzone
* Version: 1.0
*
* Func
* public download 下载处理
* public process 多进程下载
* private to_log 将执行结果写入日志文件
*/class BatchDownLoad {
// 下载文件设置
private $download_config = array(); // 最大开启进程数量
private $max_process_num = 10; // 超时秒数
private $timeout = 10; // 日志文件
private $logfile = null; /**
* 初始化
* @param Array $download_config 下载的文件设置
* @param Int $max_process_num 最大开启的进程数量
* @param Int $timeout 超时秒数
* @param String $logfile 日志文件路径
*/
public function __construct($download_config, $max_process_num=10, $timeout=10, $logfile=''){
$this->download_config = $download_config; $this->max_process_num = $max_process_num; $this->timeout = $timeout; // 日志文件
if($logfile){ $this->logfile = $logfile;
}else{ $this->logfile = dirname(__FILE__).'/batch_download_'.date('Ymd').'.log';
}
} /**
* 执行下载
* @result Int
*/
public function download(){
// 已处理的数量
$handle_num = 0; // 未处理完成
while(count($this->download_config)>0){ // 需要处理的大于最大进程数
if(count($this->download_config)>$this->max_process_num){ $process_num = $this->max_process_num; // 需要处理的小于最大进程数
}else{ $process_num = count($this->download_config);
} // 抽取指定数量进行下载
$tmp_download_config = array_splice($this->download_config, 0, $process_num); // 执行下载
$result = $this->process($tmp_download_config); // 写入日志
$this->to_log($tmp_download_config, $result); // 记录已处理的数量
$handle_num += count($result);
} return $handle_num;
} /**
* 多进程下载文件
* @param Array $download_config 本次下载的设置
* @return Array
*/
public function process($download_config){
// 文件资源
$fp = array(); // curl会话
$ch = array(); // 执行结果
$result = array(); // 创建curl handle
$mh = curl_multi_init(); // 循环设定数量
foreach($download_config as $k=>$config){ $ch[$k] = curl_init(); $fp[$k] = fopen($config[1], 'a');
curl_setopt($ch[$k], CURLOPT_URL, $config[0]);
curl_setopt($ch[$k], CURLOPT_FILE, $fp[$k]);
curl_setopt($ch[$k], CURLOPT_HEADER, 0);
curl_setopt($ch[$k], CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch[$k], CURLOPT_USERAGENT, 'Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)'); // 加入处理
curl_multi_add_handle($mh, $ch[$k]);
} $active = null; do{ $mrc = curl_multi_exec($mh, $active);
} while($active); // 获取数据
foreach($fp as $k=>$v){
fwrite($v, curl_multi_getcontent($ch[$k]));
} // 关闭curl handle与文件资源
foreach($download_config as $k=>$config){
curl_multi_remove_handle($mh, $ch[$k]);
fclose($fp[$k]); // 检查是否下载成功
if(file_exists($config[1])){ $result[$k] = true;
}else{ $result[$k] = false;
}
}
curl_multi_close($mh); return $result;
} /**
* 写入日志
* @param Array $data 下载文件数据
* @param Array $flag 下载文件状态数据
*/
private function to_log($data, $flag){
// 临时日志数据
$tmp_log = ''; foreach($data as $k=>$v){ $tmp_log .= '['.date('Y-m-d H:i:s').'] url:'.$v[0].' file:'.$v[1].' status:'.$flag[$k].PHP_EOL;
} // 创建日志目录
if(!is_dir(dirname($this->logfile))){
mkdir(dirname($this->logfile), 0777, true);
} // 写入日志文件
file_put_contents($this->logfile, $tmp_log, FILE_APPEND);
}
}?>demo.php
<?phprequire 'BatchDownLoad.class.php';$base_path = dirname(__FILE__).'/photo';$download_config = array( array('http://www.example.com/p1.jpg', $base_path.'/p1.jpg'), array('http://www.example.com/p2.jpg', $base_path.'/p2.jpg'), array('http://www.example.com/p3.jpg', $base_path.'/p3.jpg'), array('http://www.example.com/p4.jpg', $base_path.'/p4.jpg'), array('http://www.example.com/p5.jpg', $base_path.'/p5.jpg'), );$obj = new BatchDownLoad($download_config, 2, 10);$handle_num = $obj->download();echo 'download num:'.$handle_num.PHP_EOL;?>
Log output after execution
[2017-07-16 18:04:21] url:http://www.example.com/p1.jpg file:/home/fdipzone/photo/p1.jpg status:1[2017-07-16 18:04:21] url:http://www.example.com/p2.jpg file:/home/fdipzone/photo/p2.jpg status:1[2017-07-16 18:04:21] url:http://www.example.com/p3.jpg file:/home/fdipzone/photo/p3.jpg status:1[2017-07-16 18:04:21] url:http://www.example.com/p4.jpg file:/home/fdipzone/photo/p4.jpg status:1[2017-07-16 18:04:21] url:http://www.example.com/p5.jpg file:/home/fdipzone/photo/p5.jpg status:1
This article explains some ways to download files in batches. For more related content, please pay attention to php Chinese website .
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Explanation about php log classThe above is the detailed content of How to use phpcurl to implement multi-process download file classes. For more information, please follow other related articles on the PHP Chinese website!