如何使用PHP将Base64格式的图片上传到七牛云存储并生成缩略图？

composer require qiniu/php-sdk

<?php
require_once 'vendor/autoload.php'; // 引入七牛云存储的SDK

use QiniuAuth;
use QiniuStorageUploadManager;

function uploadToQiniu($accessKey, $secretKey, $bucket, $base64Image, $fileName)
{
   // 生成上传凭证
   $auth = new Auth($accessKey, $secretKey);
   $token = $auth->uploadToken($bucket);

   // 初始化上传对象
   $uploadMgr = new UploadManager();

   // 将Base64格式的图片转为二进制格式
   $fileData = base64_decode($base64Image);

   // 上传图片
   list($ret, $err) = $uploadMgr->put($token, $fileName, $fileData);

   if ($err !== null) {
       return false;
   } else {
       return true;
   }
}
?>

<?php
$accessKey = ""; // 替换为七牛云存储的accessKey
$secretKey = ""; // 替换为七牛云存储的secretKey
$bucket = ""; // 替换为七牛云存储的bucket名称
$base64Image = ""; // 替换为待上传的Base64格式图片
$fileName = ""; // 替换为上传后的文件名

if (uploadToQiniu($accessKey, $secretKey, $bucket, $base64Image, $fileName)) {
    echo "图片上传成功！";

    // 生成缩略图链接
    $thumbnailUrl = "http://".$bucket.".qnssl.com/".$fileName."?imageView2/1/w/200/h/200";
    echo "缩略图链接：".$thumbnailUrl;
} else {
    echo "图片上传失败！";
}
?>