Question

我无法弄清楚每次使用php更新时如何推进进度。为了清楚起见，我将写一个例子。

jQuery的：

function uploadMovieDownload(link){
    $.post("php/downloadmovie.php", { source:link }, function(json){ console.log(json); });
}

uploadMovieDownload(url);

PHP（php / downloadmovie.php）：

session_start();
ob_start();
date_default_timezone_set("Europe/Bucharest");
ini_set('display_errors',true);

require_once(dirname(__FILE__)."/functions.php");


$url = $_POST['source'];
$headers = getHeaders($url);
$url = $headers['url'];
$path = dirname(__FILE__)."/temp/test.mp4";

$fp = fopen ($path, 'w+');
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $url );
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, false );
curl_setopt( $ch, CURLOPT_PROGRESSFUNCTION, 'progress' );
curl_setopt( $ch, CURLOPT_NOPROGRESS, false );
curl_setopt( $ch, CURLOPT_BINARYTRANSFER, true );
curl_setopt( $ch, CURLOPT_SSL_VERIFYPEER, false );
curl_setopt( $ch, CURLOPT_CONNECTTIMEOUT, 100 );
curl_setopt( $ch, CURLOPT_FILE, $fp );
curl_exec( $ch );
curl_close( $ch );
fclose( $fp );


function progress($resource,$download_size, $downloaded, $upload_size, $uploaded){
    if($download_size > 0) echo $downloaded / $download_size  * 100;
    ob_flush();
    flush();
}

echo "Done";
ob_flush();
flush();

我遇到的问题是它在完成后返回进度，而不是在下载时推送它。如果您有任何吸烟，请提前致谢。

Answer 1

使用该方法，您将遇到所有类型的缓存问题，是php输出缓冲？你有问题。你是一个Web服务器，ala nginx / apache / lighthttp / anything？你有问题。是浏览器缓存输出？（所有主流浏览器都这样做），你会遇到问题。

我建议一个没有这些问题的替代方案：使用$ _SESSION来存储下载百分比，并使用XMLHttpRequests查询百分比（实际上查询WebSockets上的百分比将是最佳的，无滞后的，使用更少的bw等等，但是很多更难实施）

downloadmovie.php

<?php 
require_once(dirname(__FILE__)."/functions.php");


$url = $_POST['source'];
$headers = getHeaders($url);
$url = $headers['url'];
//after validation of input
session_start();
$_SESSION['download_percentage']=0.0;//initialize it
session_write_close();
fastcgi_finish_request();//or if you're not using fcgi, some equivalent..

$path = dirname(__FILE__)."/temp/test.mp4";

$fp = fopen ($path, 'w+');
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $url );
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, false );
curl_setopt( $ch, CURLOPT_PROGRESSFUNCTION, 'progress' );
curl_setopt( $ch, CURLOPT_NOPROGRESS, false );
curl_setopt( $ch, CURLOPT_BINARYTRANSFER, true );
curl_setopt( $ch, CURLOPT_SSL_VERIFYPEER, false );
curl_setopt( $ch, CURLOPT_CONNECTTIMEOUT, 100 );
curl_setopt( $ch, CURLOPT_FILE, $fp );
curl_exec( $ch );
curl_close( $ch );
fclose( $fp );


function progress($resource,$download_size, $downloaded, $upload_size, $uploaded){
    $percentage=$download_size==0? 0.0 : (($downloaded/$download_size)*100);
    session_start();
    $_SESSION['download_percentage']=$percentage;
    session_write_close();
}

getProgress.xhr.php

<?php 
if(""===session_id()){
session_start();
}
echo $_SESSION['download_percentage']??'?';

然后在浏览器中监控进度：

(function checkProgress() {
    "use strict";
    var xhr = new XMLHttpRequest();
    xhr.open("GET", "getProgress.xhr.php");
    xhr.addEventListener("readystatechange", function(ev) {
        var xhr = ev.target;
        if (xhr.readyState !== 4) {
            return;
        }
        console.log(xhr.responseText + " percent downloaded!");
        if (xhr.responseText === "100") {
            return; /*stop checking for progress when its finished*/
        }
        setTimeout(checkProgress, 1000); //<<check for progress every 1 second

    });
    xhr.send();
})();

重要编辑：正如@ drew010指出的那样，没有session_write_close（）; session_start（）;每次curl更新该值，修复该值。

Answer 2

来自cURL download progress in PHP的引用

echo "<pre>";
echo "Loading ...";

ob_flush();
flush();

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "http://stackoverflow.com");
//curl_setopt($ch, CURLOPT_BUFFERSIZE,128);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_PROGRESSFUNCTION, 'progress');
curl_setopt($ch, CURLOPT_NOPROGRESS, false); // needed to make progress function work
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);
$html = curl_exec($ch);
curl_close($ch);


function progress($resource,$download_size, $downloaded, $upload_size, $uploaded)
{
    if($download_size > 0)
         echo $downloaded / $download_size  * 100;
    ob_flush();
    flush();
    sleep(1); // just to see effect
}

echo "Done";
ob_flush();
flush();

?>

Answer 3

不要使用ob_flush（），只需使用flush（）。（删除所有ob_函数）。另外，请考虑修改buffersize：

curl_setopt($ch, CURLOPT_BUFFERSIZE, 16000);

试验尺寸。

Answer 4

PHP将在完成所有脚本后显示结果。这就是你完成进度的原因。

您可以在后台执行curl下载，并将进度写入会话，数据库，会话或内存，如redis，memchche。然后在客户端每隔很短的时间阅读一次该过程。

您也可以使用Iframe执行此操作。

PHP cURL使用jquery下载进度

4 个答案: