/**
* Download file from S3, extract it if necessary, and return a temporary URL
* pointing to the main file
*/
public static function getTemporaryURL(Zotero_Item $item, $localOnly = false)
{
$extURLPrefix = Z_CONFIG::$ATTACHMENT_SERVER_URL;
if ($extURLPrefix[strlen($extURLPrefix) - 1] != "/") {
$extURLPrefix .= "/";
}
$info = Zotero_Storage::getLocalFileItemInfo($item);
$storageFileID = $info['storageFileID'];
$filename = $info['filename'];
$mtime = $info['mtime'];
$zip = $info['zip'];
$realFilename = preg_replace("/^storage:/", "", $item->attachmentPath);
$realFilename = self::decodeRelativeDescriptorString($realFilename);
$realEncodedFilename = rawurlencode($realFilename);
$docroot = Z_CONFIG::$ATTACHMENT_SERVER_DOCROOT;
// Check memcached to see if file is already extracted
$key = "attachmentServerString_" . $storageFileID . "_" . $mtime;
if ($randomStr = Z_Core::$MC->get($key)) {
Z_Core::debug("Got attachment path '{$randomStr}/{$realEncodedFilename}' from memcached");
return $extURLPrefix . "{$randomStr}/{$realEncodedFilename}";
}
$localAddr = gethostbyname(gethostname());
// See if this is an attachment host
$index = false;
$skipHost = false;
for ($i = 0, $len = sizeOf(Z_CONFIG::$ATTACHMENT_SERVER_HOSTS); $i < $len; $i++) {
$hostAddr = gethostbyname(Z_CONFIG::$ATTACHMENT_SERVER_HOSTS[$i]);
if ($hostAddr != $localAddr) {
continue;
}
// Make a HEAD request on the local static port to make sure
// this host is actually functional
$url = "http://" . Z_CONFIG::$ATTACHMENT_SERVER_HOSTS[$i] . ":" . Z_CONFIG::$ATTACHMENT_SERVER_STATIC_PORT . "/";
Z_Core::debug("Making HEAD request to {$url}");
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_NOBODY, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, array("Expect:"));
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 1);
curl_setopt($ch, CURLOPT_TIMEOUT, 2);
curl_setopt($ch, CURLOPT_HEADER, 0);
// do not return HTTP headers
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$response = curl_exec($ch);
$code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
if ($code != 200) {
$skipHost = Z_CONFIG::$ATTACHMENT_SERVER_HOSTS[$i];
if ($code == 0) {
Z_Core::logError("Error connecting to local attachments server");
} else {
Z_Core::logError("Local attachments server returned {$code}");
}
break;
}
$index = $i + 1;
break;
}
// If not, make an internal root request to trigger the extraction on
// one of them and retrieve the temporary URL
if ($index === false) {
// Prevent redirect madness if target server doesn't think it's an
// attachment server
if ($localOnly) {
throw new Exception("Internal attachments request hit a non-attachment server");
}
$prefix = 'http://' . Z_CONFIG::$API_SUPER_USERNAME . ":" . Z_CONFIG::$API_SUPER_PASSWORD . "@";
$path = Zotero_API::getItemURI($item) . "/file/view?int=1";
$path = preg_replace('/^[^:]+:\\/\\/[^\\/]+/', '', $path);
$context = stream_context_create(array('http' => array('follow_location' => 0)));
$url = false;
$hosts = Z_CONFIG::$ATTACHMENT_SERVER_HOSTS;
// Try in random order
shuffle($hosts);
foreach ($hosts as $host) {
// Don't try the local host again if we know it's not working
if ($host == $skipHost) {
continue;
}
$intURL = $prefix . $host . ":" . Z_CONFIG::$ATTACHMENT_SERVER_DYNAMIC_PORT . $path;
Z_Core::debug("Making GET request to {$host}");
if (file_get_contents($intURL, false, $context) !== false) {
foreach ($http_response_header as $header) {
if (preg_match('/^Location:\\s*(.+)$/', $header, $matches)) {
if (strpos($matches[1], $extURLPrefix) !== 0) {
throw new Exception("Redirect location '" . $matches[1] . "'" . " does not begin with {$extURLPrefix}");
}
return $matches[1];
}
}
}
}
return false;
}
// If this is an attachment host, do the download/extraction inline
// and generate a random number with an embedded host id.
//
// The reverse proxy routes incoming file requests to the proper hosts
// using the embedded id.
//
// A cron job deletes old attachment directories
$randomStr = rand(1000000, 2147483647);
// Seventh number is the host id
$randomStr = substr($randomStr, 0, 6) . $index . substr($randomStr, 6);
// Download file
$dir = $docroot . $randomStr . "/";
$downloadDir = $zip ? $dir . "ztmp/" : $dir;
Z_Core::debug("Downloading attachment to {$dir}");
if (!mkdir($downloadDir, 0777, true)) {
throw new Exception("Unable to create directory '{$downloadDir}'");
}
if ($zip) {
$response = Zotero_Storage::downloadFile($info, $downloadDir);
} else {
$response = Zotero_Storage::downloadFile($info, $downloadDir, $realFilename);
}
if ($response) {
if ($zip) {
$success = self::extractZip($downloadDir . $info['filename'], $dir);
unlink($downloadDir . $info['filename']);
rmdir($downloadDir);
// Make sure charset is just a string with no spaces or newlines
if (preg_match('/^[^\\s]+/', trim($item->attachmentCharset), $matches)) {
$charset = $matches[0];
} else {
$charset = 'Off';
}
file_put_contents($dir . ".htaccess", "AddDefaultCharset " . $charset);
} else {
$success = true;
if (preg_match('/^[^\\s]+/', trim($item->attachmentContentType), $matches)) {
$contentType = $matches[0];
$charset = trim($item->attachmentCharset);
if (substr($charset, 0, 5) == 'text/' && preg_match('/^[^\\s]+/', $charset, $matches)) {
$contentType .= '; ' . $matches[0];
}
file_put_contents($dir . ".htaccess", "ForceType " . $contentType);
}
}
}
if (!$response || !$success) {
return false;
}
Z_Core::$MC->set($key, $randomStr, self::$cacheTime);
return $extURLPrefix . "{$randomStr}/" . $realEncodedFilename;
}
public static function patchFile($item, $info, $algorithm, $patch)
{
switch ($algorithm) {
case 'bsdiff':
case 'xdelta':
case 'vcdiff':
break;
case 'xdiff':
if (!function_exists('xdiff_file_patch_binary')) {
throw new Exception("=xdiff not available");
}
break;
default:
throw new Exception("Invalid algorithm '{$algorithm}'", Z_ERROR_INVALID_INPUT);
}
$originalInfo = Zotero_Storage::getLocalFileItemInfo($item);
$basePath = "/tmp/zfsupload/";
$path = $basePath . $info->hash . "_" . uniqid() . "/";
mkdir($path, 0777, true);
$cleanup = function () use($basePath, $path) {
unlink("original");
unlink("patch");
unlink("new");
chdir($basePath);
rmdir($path);
};
$e = null;
try {
// Download file from S3 to temp directory
if (!Zotero_Storage::downloadFile($originalInfo, $path, "original")) {
throw new Exception("Error downloading original file");
}
chdir($path);
// Save body to temp file
file_put_contents("patch", $patch);
// Patch file
switch ($algorithm) {
case 'bsdiff':
exec('bspatch original new patch 2>&1', $output, $ret);
if ($ret) {
throw new Exception("Error applying patch ({$ret}): " . implode("\n", $output));
}
if (!file_exists("new")) {
throw new Exception("Error applying patch ({$ret})");
}
break;
case 'xdelta':
case 'vcdiff':
exec('xdelta3 -d -s original patch new 2>&1', $output, $ret);
if ($ret) {
if ($ret == 2) {
throw new Exception("Invalid delta", Z_ERROR_INVALID_INPUT);
}
throw new Exception("Error applying patch ({$ret}): " . implode("\n", $output));
}
if (!file_exists("new")) {
throw new Exception("Error applying patch ({$ret})");
}
break;
case 'xdiff':
$ret = xdiff_file_patch_binary("original", "patch", "new");
if (!$ret) {
throw new Exception("Error applying patch");
}
break;
}
// Check MD5 hash
if (md5_file("new") != $info->hash) {
$cleanup();
throw new HTTPException("Patched file does not match hash", 409);
}
// Check file size
if (filesize("new") != $info->size) {
$cleanup();
throw new HTTPException("Patched file size does not match " . "(" . filesize("new") . " != {$info->size})", 409);
}
// If ZIP, make sure it's a ZIP
if ($info->zip && file_get_contents("new", false, null, 0, 4) != "PK" . chr(03) . chr(04)) {
$cleanup();
throw new HTTPException("Patched file is not a ZIP file", 409);
}
// Upload to S3
$t = $info->contentType . ($info->contentType && $info->charset ? "; charset={$info->charset}" : "");
$storageFileID = Zotero_Storage::uploadFile($info, "new", $t);
} catch (Exception $e) {
//$cleanup();
throw $e;
}
return $storageFileID;
}
