Google 雲端硬碟檔案下載，CURL 跟隨301, 302轉址找到最後下載（網站）連結範例

google-driver-file-downloader.php

<?php

//Ref: http://php.net/manual/en/ref.curl.php#93163
function get_final_url($url, $cookie = "", $timeout = 5) {
	$url = str_replace("&amp;", "&", urldecode(trim($url)));
	//保留餅乾資訊
	if ($cookie == "") {
		$cookie = tempnam(sys_get_temp_dir(), "mxp_");
	}
	//假一下瀏覽器請求
	$user_agent = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36";
	//CURL 初始化
	$ch = curl_init();
	curl_setopt($ch, CURLOPT_USERAGENT, $user_agent);
	curl_setopt($ch, CURLOPT_URL, $url);
	curl_setopt($ch, CURLOPT_COOKIEJAR, $cookie);
	curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
	curl_setopt($ch, CURLOPT_ENCODING, "");
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
	curl_setopt($ch, CURLOPT_AUTOREFERER, true);
	curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
	curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
	curl_setopt($ch, CURLOPT_MAXREDIRS, 10);
	$content = curl_exec($ch);
	$response = curl_getinfo($ch);
	curl_close($ch);
	//設定根層級的假請求
	ini_set("user_agent", $user_agent);
	//請求標頭
	$headers = get_headers($response['url']);
	//判斷是否有 301, 302 轉址
	if ($response['http_code'] == 301 || $response['http_code'] == 302) {
		$location = "";
		foreach ($headers as $value) {
			if (substr(strtolower($value), 0, 9) == "location:") {
				//取得轉址的連結，遞迴請求
				return get_final_url(trim(substr($value, 9, strlen($value))), $cookie);
			}
		}
	}
	$filename = "";
	foreach ($headers as $value) {
		if (substr(strtolower($value), 0, 20) == "content-disposition:") {
			//如果有檔案名稱資訊，就存下來等等下載用
			$filename = urldecode(trim(substr($value, 20, strlen($value))));
		}
	}

	//如果不是使用 301, 302 轉址，可能網頁內容會有 JavaScript 或提示轉址資訊，可以在這裡分析
	// if (preg_match("/window\.location\.replace\('(.*)'\)/i", $content, $value) ||
	// 	preg_match("/window\.location\=\"(.*)\"/i", $content, $value)
	// ) {
	// 	return get_final_url($value[1]);
	// }

	//把最後的連結檔案下載回去
	$filename = explode("''", $filename);
	$fp = fopen($filename[1], 'w');
	$ch = curl_init($response['url']);
	curl_setopt($ch, CURLOPT_USERAGENT, $user_agent);
	curl_setopt($ch, CURLOPT_FILE, $fp);
	$data = curl_exec($ch);
	curl_close($ch);
	fclose($fp);
	return array("filename" => $filename[1], "url" => $response['url']);
}
print_r(get_final_url('https://drive.google.com/uc?export=download&id=0B21MNCxxxxxxxxxxxxxxxxxxx1xdVk'));