<?php
class Download
{
/**
* @var false|resource
*/
private static $curlHandle = false;
/**
* Common initialization for download and downloadToFile
* Return file handle to header file
* @return false|resource
*/
private static function initCurl(string $url, int $timeout, &$head)
{
if (self::$curlHandle === false) {
self::$curlHandle = curl_init();
if (self::$curlHandle === false) {
ErrorHandler::traceError('Could not initialize cURL');
}
curl_setopt(self::$curlHandle, CURLOPT_CONNECTTIMEOUT, ceil($timeout / 2));
curl_setopt(self::$curlHandle, CURLOPT_TIMEOUT, $timeout);
curl_setopt(self::$curlHandle, CURLOPT_FOLLOWLOCATION, true);
curl_setopt(self::$curlHandle, CURLOPT_AUTOREFERER, true);
curl_setopt(self::$curlHandle, CURLOPT_BINARYTRANSFER, true);
curl_setopt(self::$curlHandle, CURLOPT_MAXREDIRS, 6);
}
curl_setopt(self::$curlHandle, CURLOPT_URL, $url);
$tmpfile = tempnam('/tmp/', 'bwlp-');
$head = fopen($tmpfile, 'w+b');
unlink($tmpfile);
if ($head === false)
ErrorHandler::traceError("Could not open temporary head file $tmpfile for writing.");
curl_setopt(self::$curlHandle, CURLOPT_WRITEHEADER, $head);
return self::$curlHandle;
}
/**
* Read 10kb from the given file handle, seek to 0 first,
* close the file after reading. Returns data read
*/
private static function getContents($fh)
{
fseek($fh, 0, SEEK_SET);
$data = fread($fh, 10000);
fclose($fh);
return $data;
}
/**
* Download file, obey given timeout in seconds
* Return data on success, false on failure
*/
public static function asString(string $url, int $timeout, &$code)
{
$ch = self::initCurl($url, $timeout, $head);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$data = curl_exec($ch);
$head = self::getContents($head);
if (preg_match_all('#^HTTP/\d+\.\d+ (\d+) #m', $head, $out)) {
$code = (int) array_pop($out[1]);
} else {
$code = 999;
}
return $data;
}
/**
* POST-Download file, obey given timeout in seconds
* Return data on success, false on failure
* @param string $url URL to fetch
* @param array|false $params POST params to set in body, list of key-value-pairs
* @param int $timeout timeout in seconds
* @param int $code HTTP response code, or 999 on error
*/
public static function asStringPost(string $url, $params, int $timeout, &$code)
{
$string = '';
if (is_array($params)) {
foreach ($params as $k => $v) {
if (!empty($string)) {
$string .= '&';
}
$string .= $k . '=' . urlencode($v);
}
}
$ch = self::initCurl($url, $timeout, $head);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $string);
$data = curl_exec($ch);
$head = self::getContents($head);
if (preg_match_all('#^HTTP/\d+\.\d+ (\d+) #m', $head, $out)) {
$code = (int) array_pop($out[1]);
} else {
$code = 999;
}
return $data;
}
/**
* Download a file from a URL to file.
*
* @param string $target destination path to download file to
* @param string $url URL of file to download
* @param int $timeout timeout in seconds
* @param int $code HTTP status code passed out by reference
* @return boolean
*/
public static function toFile(string $target, string $url, int $timeout, &$code): bool
{
$fh = fopen($target, 'wb');
if ($fh === false)
ErrorHandler::traceError("Could not open $target for writing.");
$ch = self::initCurl($url, $timeout, $head);
curl_setopt($ch, CURLOPT_FILE, $fh);
$res = curl_exec($ch);
$head = self::getContents($head);
fclose($fh);
if ($res === false) {
@unlink($target);
return false;
}
if (preg_match_all('#^HTTP/\d+\.\d+ (\d+) #m', $head, $out)) {
$code = (int) array_pop($out[1]);
} else {
$code = '999 ' . curl_error($ch);
}
return true;
}
}
