无法从linux中的php访问我的Dropbox帐户

我下载了dropbox php sdk。好啊 接下来,我在php上编写脚本:

<?php
require_once "dropbox-sdk-php-1.1.6/lib/Dropbox/autoload.php";

use \Dropbox as dbx;

$dropbox_config = array(
    'key'    => 'fasgsasgas',
    'secret' => 'gasawggasg'
);

$appInfo = dbx\AppInfo::loadFromJson($dropbox_config);
$webAuth = new dbx\WebAuthNoRedirect($appInfo, "PHP-Example/1.0");

$authorizeUrl = $webAuth->start();
echo "1. Go to: " . $authorizeUrl . "<br>";
echo "2. Click \"Allow\" (you might have to log in first).<br>";
echo "3. Copy the authorization code and insert it into $authCode.<br>";

$authCode = trim('eadasfafasfasfasfffffasfasfsafsafsafsafsafafa');

list($accessToken, $dropboxUserId) = $webAuth->finish($authCode);
echo "Access Token: " . $accessToken . "<br>";

$dbxClient = new dbx\Client($accessToken, "PHP-Example/1.0");

$accountInfo = $dbxClient->getAccountInfo();
print_r($accountInfo);
?>

当我运行这个脚本时,我有输出:

root@iredmail:/var/www/test.tl# php test2.php
PHP Fatal error:  Uncaught exception 'Exception' with message 'The Dropbox SDK requires the cURL PHP extension, but it looks like you don't have it (couldn't find function "curl_init").  Library: "/var/www/test.tl/dropbox-sdk-php-1.1.6/lib/Dropbox/RequestUtil.php".' in /var/www/test.tl/dropbox-sdk-php-1.1.6/lib/Dropbox/RequestUtil.php:5
Stack trace:
#0 /var/www/test.tl/dropbox-sdk-php-1.1.6/lib/Dropbox/autoload.php(27): require_once()
#1 [internal function]: Dropbox\autoload('Dropbox\Request...')
#2 /var/www/test.tl/dropbox-sdk-php-1.1.6/lib/Dropbox/WebAuthBase.php(14): spl_autoload_call('Dropbox\Request...')
#3 /var/www/test.tl/dropbox-sdk-php-1.1.6/lib/Dropbox/WebAuthNoRedirect.php(56): Dropbox\WebAuthBase->_getAuthorizeUrl(NULL, NULL)
#4 /var/www/test.tl/test2.php(14): Dropbox\WebAuthNoRedirect->start()
#5 {main}
  thrown in /var/www/test.tl/dropbox-sdk-php-1.1.6/lib/Dropbox/RequestUtil.php on line 5

在哪里,我有一个错误?我需要获取帐户信息。但我不明白,我犯了错误。