$upload_url = 'http://192.168.0.99:5000/upload';

$image_file = './test.jpg';

// 获取图片后缀
$value = explode(".", $image_file);
$extension = strtolower(array_pop($value));

// 生成本地临时存储路径，并生成相应文件夹
$dir = 'aurthur';
$save_path = 'uploads/'.$dir.'/'.date('Y').'/'.date('md').'/';
$save_rule = md5(uniqid(mt_rand(), true));
if(!is_dir($save_path)){
  if(false === mkdir($save_path, 0700, true)){
    exit('创建文件夹失败');
  }
}
$save_image_file = $save_path.$save_rule.".$extension";

// 把图片存储到临时路径
file_put_contents($save_image_file, file_get_contents($image_file));

// 获取临时保存的图片的真实地址(绝对路径)
$realpath = realpath($save_image_file);

// 上传图片到 zimg 图片存储服务
$ch = curl_init();

// 将图片内容读取到变量 $post_data ;
$post_data = file_get_contents($realpath);

$headers = array();
// 一定要添加此 header
$headers[] = 'Content-Type:'.$extension;

curl_setopt($ch, CURLOPT_URL, $upload_url);
curl_setopt($ch, CURLOPT_HEADER, false);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

curl_setopt($ch, CURLOPT_POST, true); 
curl_setopt($ch, CURLOPT_BINARYTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);// raw_post方式

$info = curl_exec($ch);
curl_close($ch);

$json = json_decode($info, true);
$signature = $json['info']['md5'];
echo $signature;