I am using Guzzle 6 to update products to shopify via API. I am using async post method to upload products in bulk, but in response if any error occur in any posted requests , I am unable to find out which requests cause this error. As response come only after completion of async function. Any solution to this ? How can we find out postAsync requests cause error , so that we can store status of failed and success requests individually ? Also, post request limit is 2calls per second as per shopify.

I am using this code:

   $client = new Client();
$url = "https://optimze-test.myshopify.com/admin/api/2019-07/products.json";
        $promises = (function () use ($main_array,$client,$ShopifyHeaders,$url) {
          foreach ($main_array as $project) {
            // don't forget using generator
            yield $client->postAsync($url,['json' => $project,'headers'=>$ShopifyHeaders]);   
          }
        })();

        $eachPromise = new EachPromise($promises, [
          // how many concurrency we are use
          'concurrency' => 10,
          'fulfilled' => function (Response $response) {
            if ($response->getStatusCode() == 200) {
              $data = json_decode($response->getBody(), true);
                // processing response of user here
                echo "successes";
                Log::info('success::'.$data);
              }
            },
          'rejected' => function ($reason) {
            // handle promise rejected here
            echo "fail";
            Log::info('fail::'.$reason);
          }
        ]);

        $eachPromise->promise()->wait();

Where $main_array is array of data of products to be posted .