<?php
namespace Aws;
use Aws\Signature\SignatureV4;
use Aws\Endpoint\EndpointProvider;
use GuzzleHttp\Psr7\Uri;
use Psr\Http\Message\RequestInterface;
/**
* @internal Adds computed values to service operations that need presigned url.
*/
class PresignUrlMiddleware
{
private $client;
private $endpointProvider;
private $nextHandler;
/** @var array names of operations that require presign url */
private $commandPool;
/** @var array query params that are not on the operation's model to add before signing */
private $extraQueryParams;
/** @var string */
private $serviceName;
/** @var string */
private $presignParam;
/** @var bool */
private $requireDifferentRegion;
public function __construct(
array $options,
callable $endpointProvider,
AwsClientInterface $client,
callable $nextHandler
) {
$this->endpointProvider = $endpointProvider;
$this->client = $client;
$this->nextHandler = $nextHandler;
$this->commandPool = $options['operations'];
$this->serviceName = $options['service'];
$this->presignParam = !empty($options['presign_param'])
? $options['presign_param']
: 'PresignedUrl';
$this->extraQueryParams = !empty($options['extra_query_params'])
? $options['extra_query_params']
: [];
$this->requireDifferentRegion = !empty($options['require_different_region']);
}
public static function wrap(
AwsClientInterface $client,
callable $endpointProvider,
array $options = []
) {
return function (callable $handler) use ($endpointProvider, $client, $options) {
$f = new PresignUrlMiddleware($options, $endpointProvider, $client, $handler);
return $f;
};
}
public function __invoke(CommandInterface $cmd, RequestInterface $request = null)
{
if (in_array($cmd->getName(), $this->commandPool)
&& (!isset($cmd->{'__skip' . $cmd->getName()}))
) {
$cmd['DestinationRegion'] = $this->client->getRegion();
if (!empty($cmd['SourceRegion']) && !empty($cmd[$this->presignParam])) {
goto nexthandler;
}
if (!$this->requireDifferentRegion
|| (!empty($cmd['SourceRegion'])
&& $cmd['SourceRegion'] !== $cmd['DestinationRegion'])
) {
$cmd[$this->presignParam] = $this->createPresignedUrl($this->client, $cmd);
}
}
nexthandler:
$nextHandler = $this->nextHandler;
return $nextHandler($cmd, $request);
}
private function createPresignedUrl(
AwsClientInterface $client,
CommandInterface $cmd
) {
$cmdName = $cmd->getName();
$newCmd = $client->getCommand($cmdName, $cmd->toArray());
// Avoid infinite recursion by flagging the new command.
$newCmd->{'__skip' . $cmdName} = true;
// Serialize a request for the operation.
$request = \Aws\serialize($newCmd);
// Create the new endpoint for the target endpoint.
$endpoint = EndpointProvider::resolve($this->endpointProvider, [
'region' => $cmd['SourceRegion'],
'service' => $this->serviceName,
])['endpoint'];
// Set the request to hit the target endpoint.
$uri = $request->getUri()->withHost((new Uri($endpoint))->getHost());
$request = $request->withUri($uri);
// Create a presigned URL for our generated request.
$signer = new SignatureV4($this->serviceName, $cmd['SourceRegion']);
$currentQueryParams = (string) $request->getBody();
$paramsToAdd = false;
if (!empty($this->extraQueryParams[$cmdName])) {
foreach ($this->extraQueryParams[$cmdName] as $param) {
if (!strpos($currentQueryParams, $param)) {
$paramsToAdd = "&{$param}={$cmd[$param]}";
}
}
}
return (string) $signer->presign(
SignatureV4::convertPostToGet($request, $paramsToAdd ?: ""),
$client->getCredentials()->wait(),
'+1 hour'
)->getUri();
}
}