How to add descriptions to uploaded photos in a VK album?

Question

PHP

There is a script that loads up to 5 (the maximum allowed by the VK API) photos. Uploading according to the documentation:
1. get a token
2. get a link for uploading to the server
3. send a POST request with files
4. after uploading, save using the photos.save method
Here is a plug at the 4th point. I need to add a specific description to each photo, and the photos.save method, judging by the documentation, can only add a description to the entire pool of photos. How to attribute description in my case? I would like to avoid POST requests in a single file loop.
Download function:

public static function uploadImages($files, $group_id, $album_id)
    {

        //Получаем сервер для загрузки изображения
        $params = array(
            'group_id'  =>   $group_id,
            'album_id'  =>   $album_id
            );
        $api_res = self::queryApi("photos.getUploadServer", $params);

        try
        {
            if($api_res)
            {
                $server = $api_res->response->upload_url;
                $post = array();

                    $query = self::$connection->query("SELECT * FROM `images` WHERE `id` IN (".$files.");");
                    if($query)
                    {
                        $i = 1;
                        while($row = $query->fetch_assoc())
                        {
                            if(!empty($row['image'])){
                                if(file_exists(config::$full_path.'images//'.$row['image'])){
                                    $img = $row['image'];
                                }else{
                                    $img = 'no-image.jpg';
                                }
                            }else{
                                $img = 'no-image.jpg'; 
                            }

                            $post['file'.$i] = new CURLFile(config::$full_path.'images/'.$img);
                            $i++;
                        }
                    }else
                        throw new Exception("Ошибка при запросе в базу данных. Error: ".self::$connection->error, 1);


                if($ch = curl_init($server))
                {
                    curl_setopt($ch, CURLOPT_POST, true);
                    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
                    curl_setopt($ch, CURLOPT_POSTFIELDS,$post);
                    $json = json_decode(curl_exec($ch));
                    curl_close($ch);

                    $params_save = array(
                            'server'    =>  $json->server,
                            'photos_list'   =>  $json->photos_list,
                            'album_id'  =>  $album_id,
                            'hash'  =>  $json->hash,
                            'group_id'   =>  $group_id,
                            'caption'   =>  'test message for checking uploading photos to VK.com'   //вот это описание припишется ВСЕМ фотографиям, загружаемым в одном запросе
                        );

                    $photo_save = self::queryApi('photos.save', $params_save);

                    if($photo_save)
                    {
                        return $photo_save;
                    }
                    else throw new Exception("При сохранении фотографий в альбом произошла ошибка.", 1);
                }
                else throw new Exception("Ошибка инициализации cURL", 1);
            }
            else throw new Exception("При обращении к API photos.getUploadServer произошла ошибка.", 1);
        }catch(Exception $e){
            echo $e->getMessage();
            return false;
        }
    }

API call function:

public static function queryApi($api, $params = null, $type = 0)
    {

        //своеобразный костыль-хак, чтоб не писать отдельную функцию для авторизации =)
        //если пришел 0-обращение к АПИ, если что-то другое (1) - попытка авторизации
        if($type == 0)
        {
            $server = 'https://api.vk.com/method/';
        }else{
            $server = 'https://oauth.vk.com/';
        }

        $params['access_token'] = $_SESSION['vk']['access_token'];
        $params['v'] = config::$vk_api['ver'];

        $postparams = http_build_query($params);

        try{
            if($curl = curl_init()) 
            {
                curl_setopt($curl, CURLOPT_URL, $server.$api);
                curl_setopt($curl, CURLOPT_RETURNTRANSFER,true);
                curl_setopt($curl, CURLOPT_POST, true);
                curl_setopt($curl, CURLOPT_POSTFIELDS, $postparams);
                $result = json_decode(curl_exec($curl));
                curl_close($curl);

                if(isset($result->error))
                {
                    //Шаблон для ошибок
                    if($type == 0)
                    {
                        $error_msg = "При запросе к VK API возникла ошибка. ERROR CODE: ".$result->error->error_code."; MESSAGE: ".$result->error->error_msg;
                    }else{
                        $error_msg = "При попытке авторизации произошла ошибка. ERROR: ".$result->error."; DESCRIPTION: ".$result->error_description;
                    }

                    throw new Exception($error_msg, 1);
                }
                else
                {
                    return $result;                        
                }

            }
            else
            {
                throw new Exception("Ошибка инициализации модуля cURL.", 1);
            }
        }catch(Exception $e){
            echo $e->getMessage();
            return false;
        }
    }

Answer 1

In general, when loading a pack - no way. I implemented something like this:
when selecting images, each is added to the JS array, then on click, a recursive timer starts working, which sends an ajax request to the PHP script. After the response from PHP, if everything is successful, this image is removed from the array and the next one is sent. And so on, until the array ends. VK API limits are imposed on the number of hits per second, but nothing else came to mind.
JS code:

function sendForm(items, group_id, album_id)
  {

      function ajaxQuery()
      {
        $.ajax({ 
                    type: 'POST',   
                    url: 'loader.php',    
                    data: 'action=loadPhoto&group_id='+group_id+'&album_id='+album_id+'&items='+items.splice(0, qps),
                    success: function(result){   
                    	if (result == 'ok') {
                      		item_selected = items.length;
                      		checked.html(item_selected);
                      		alert(result+" : "+loaded);
                      	}
                      	else
                      		alert(result);
                    }
            	});
      }

    $('body').append('<div class="loading">');
    //осторожно - РЕКУРСИЯ
    var timerId = setTimeout(function tick() {
      if(items.length>0){
        $.when(ajaxQuery()).done(function(){timerId = setTimeout(tick, 1200);});	//вот тут
      }
      else
      {
        clearTimeout(timerId);
        alert("Выбранные товары загружены!");
        loadItems(1);
        loadPagesCount();
        $('div.loading').remove();
      }
    }, 0);
  }

loader.php file code

require_once './functions.php';
$func = new functions;

if($_POST['action'] == 'loadPhoto' && !empty($_POST['group_id']) && !empty($_POST['album_id']) && !empty($_POST['items']))
{
  $images = explode(",", $_POST['items']);
  for ($i=0; $i < count($images); $i++) { 
    $photo_load = $func->uploadImages($images[$i], $_POST['group_id'], $_POST['album_id']);
    if($photo_load)
      $result = true;
    else
      $result = false;
  }

  if($result)
    echo "ok";
  else
  {
    echo "ERROR:";
    print_r($photo_load);
  }
}

uploadImages function in functions.php class:

public static function uploadImages($file, $group_id, $album_id)
    {

        //Получаем сервер для загрузки изображения
        $params = array(
            'group_id'  =>   $group_id,
            'album_id'  =>   $album_id
            );
        $api_res = self::queryApi("photos.getUploadServer", $params);

        try
        {
            if($api_res)
            {
                $server = $api_res->response->upload_url;
                $post = array();

                    $query = self::$connection->query("SELECT * FROM `product`, `product_price` WHERE `product`.`product_id`='".$file."' AND `product_price`.`product_id`='".$file."';");
                    if($query)
                    {
                        while($row = $query->fetch_assoc())
                        {
                            if(!empty($row['product_full_image'])){
                                if(file_exists(config::$full_path.'images/shop/product/'.$row['product_full_image'])){
                                    $img = $row['product_full_image'];
                                }else{
                                    $img = 'no-image.jpg';
                                }
                            }else if(!empty($row['product_thumb_image']))
                            {
                                if(file_exists(config::$full_path.'images/shop/product/'.$row['product_thumb_image'])){
                                    $img = $row['product_thumb_image'];
                                }else{
                                    $img = 'no-image.jpg';
                                }
                            }else{
                                $img = 'no-image.jpg'; 
                            }

                            $product_desc = $row['product_desc'];
                            $product_price = $row['product_price'];

                            //PHP 5.5+ use 'new CURLFile()' PHP 5.4- use @file_path
                            //$post['file1'] = new CURLFile(config::$full_path.'images/shop/product/'.$img);
                            $post['file1'] = '@'.config::$full_path.'images/shop/product/'.$img;
                        }
                    }else
                        throw new Exception("Ошибка при запросе в базу данных. Error: ".self::$connection->error, 1);


                if($ch = curl_init($server))
                {
                    curl_setopt($ch, CURLOPT_POST, true);
                    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
                    curl_setopt($ch, CURLOPT_POSTFIELDS,$post);
                    $json = json_decode(curl_exec($ch));
                    curl_close($ch);

                    $params_save = array(
                            'server'    =>  $json->server,
                            'photos_list'   =>  $json->photos_list,
                            'album_id'  =>  $album_id,
                            'hash'  =>  $json->hash,
                            'group_id'   =>  $group_id,
                            'caption'   =>  $product_desc.' Цена: '. $product_price . 'руб.'
                        );

                    $photo_save = self::queryApi('photos.save', $params_save);

                    if($photo_save)
                    {
                        return $photo_save;
                    }
                    else throw new Exception("При сохранении фотографий в альбом произошла ошибка.", 1);
                }
                else throw new Exception("Ошибка инициализации cURL", 1);
            }
            else throw new Exception("При обращении к API photos.getUploadServer произошла ошибка.", 1);
        }catch(Exception $e){
            echo $e->getMessage();
            return false;
        }
    }

I hope that my method will help someone)
PS: in my case, the product IDs were transferred to the database, which then pulled out the image.