Response logging in AWS PHP SDK v3

In v2 of the AWS PHP SDK, I was able to setup logging of request and response information by simply doing this:

<?php
use MonologLogger;
use GuzzleLogMonologLogAdapter;
use GuzzlePluginLogLogPlugin;
use AwsS3S3Client;
$monolog = new Logger('main');
$monolog_adapter = new MonologLogAdapter($monolog);
$log_plugin = new LogPlugin($monolog_adapter);
$s3_client = S3Client::factory(['region' => 'us-east-1']);
$s3_client->addSubscriber($log_plugin);
var_dump($s3_client->doesObjectExist('my-bucket', 'object-that-doesnt-exist'));

# This is the log entry I want in the v3 version:
# [2015-10-30 14:47:20] main.ERROR: myhostname aws-sdk-php2/2.8.20 Guzzle/3.9.3 curl/7.43.0 PHP/5.5.23 - [2015-10-30T14:47:20+00:00] "HEAD /my-bucket/object-that-doesnt-exist HTTP/1.1" 404  ...
# bool(false)

In v3, I cannot seem to find the solution. Middlewares do not seem helpful as they only fire before the request is sent, and thus I cannot access the response HTTP code.

Guzzle v6 has this feature built into its Middlewares, but I do not know how to get it to work with the aws-php-sdk. https://github.com/guzzle/guzzle/blob/master/src/Middleware.php#L180

The closest I got was this:

<?php
use MonologLogger;
use GuzzleHttpMessageFormatter;
use GuzzleHttpMiddleware;
use GuzzleHttpHandlerStack;
use AwsS3S3Client;
$monolog = new Logger('main');
$guzzle_formatter = new MessageFormatter(MessageFormatter::CLF);
$guzzle_log_middleware = Middleware::log($monolog, $guzzle_formatter);
$guzzle_stack = HandlerStack::create();
$guzzle_stack->push($guzzle_log_middleware);
$s3_client = new S3Client([
    'region' => 'us-east-1',
    'version' => '2006-03-01',
    'http_handler' => $guzzle_stack,
]);
var_dump($s3_client->doesObjectExist('my-bucket', 'object-that-doesnt-exist'));

# [2015-10-30 15:10:12] main.INFO: myhostname aws-sdk-php/3.9.2 - [30/Oct/2015:15:10:12 +0000] "HEAD /my-bucket/object-that-doesnt-exist HTTP/1.1" 404  [] []
# bool(true)

However, while the logging works, doesObjectExist() now returns the incorrect value because this handler does not throw an exception for 404, which the aws-php-sdk expects to happen. Some other simple requests like uploading to S3 seemed to work at first glance. Not sure where else there could be issues with this method.

Answer

The handler used in the SDK is a bit different from the one used in Guzzle. You’re creating a Guzzle handler correctly, and to pass that into the SDK, you would need to create an adapter like so:

<?php

use AwsHandlerGuzzleV6GuzzleHandler;
use AwsS3S3Client;
use MonologLogger;
use GuzzleHttpClient;
use GuzzleHttpMessageFormatter;
use GuzzleHttpMiddleware;
use GuzzleHttpHandlerStack;

$guzzle_stack = HandlerStack::create();
$guzzle_stack->push(Middleware::log(
    new Logger('main'), 
    new MessageFormatter(MessageFormatter::CLF)
));

$handler = new GuzzleHandler(new Client(['handler' => $guzzle_stack]));

$s3_client = new S3Client([
    'region' => 'us-east-1',
    'version' => '2006-03-01',
    'http_handler' => $handler,
]);

var_dump($s3_client->doesObjectExist('my-bucket', 'object-that-doesnt-exist'));

The GuzzleHandler object converts HTTP errors to exceptions.