[留存备份]PHP SFTP下载文件代码

太忙，流程分析待补

代码来源：https://randomdrake.com/2012/02/08/listing-and-downloading-files-over-sftp-with-php-and-ssh2/

[code lang="php"]<?php
// Make our connection
$connection = ssh2_connect('ftp.somehost.com');
// Authenticate
if (!ssh2_auth_password($connection, 'username', 'password')) 
 throw new Exception('Unable to connect.');

// Create our SFTP resource
if (!$sftp = ssh2_sftp($connection)) 
 throw new Exception('Unable to create SFTP connection.');

/**
 * Now that we have our SFTP resource, we can open a directory resource
 * to get us a list of files. Here we will use the $sftp resource in
 * our address string as I previously mentioned since our ssh2://
 * protocol allows it.
 */
$files = array();
$dirHandle = opendir("ssh2.sftp://$sftp/");
// Properly scan through the directory for files, ignoring directory indexes (. & ..)
while (false !== ($file = readdir($dirHandle))) 
 if ($file != '.' && $file != '..') 
 $files[] = $file;
 

/**
 * Using our newly created list of files, we can go about downloading. We will
 * open a remote stream and a local stream and write from one to the other.
 * We will use error suppression on the fopen call to suppress warnings from
 * not being able to open the file.
 */
if (count($files)) 
 foreach ($files as $fileName) 
 // Remote stream
 if (!$remoteStream = @fopen("ssh2.sftp://$sftp/$fileName", 'r')) 
 throw new Exception("Unable to open remote file: $fileName");
 
 // Local stream
 if (!$localStream = @fopen("/localdir/$fileName", 'w')) 
 throw new Exception("Unable to open local file for writing: /localdir/$fileName");
 
 // Write from our remote stream to our local stream
 $read = 0;
 $fileSize = filesize("ssh2.sftp://$sftp/$fileName");
 while ($read < $fileSize && ($buffer = fread($remoteStream, $fileSize - $read))) 
 // Increase our bytes read
 $read += strlen($buffer);
 // Write to our local file
 if (fwrite($localStream, $buffer) === FALSE) 
 throw new Exception("Unable to write to local file: /localdir/$fileName");
 
 
 // Close our streams
 fclose($localStream);
 fclose($remoteStream);
 
[/code]