The latest update to aws-sdk-php seems to break sidecar. All functions return error in sidecar. However function runs successfully on lambda.

I have traced issue down to the isError() function in src/Results/SettledResult.php, which checks value of 'FunctionError" in the returned aws response.

return $this->raw->get('FunctionError') !== '';

With aws-sdk-php < 3.351.9

the key FunctionError is always available in raw from AWS and is empty when no error present.

With aws-sdk-php = 3.351.10

FunctionError does not exits in the raw AWS response (at least not on a successful one) with the latest version of the sdk and so isError is always true!