public function createSqsPolicy()
    {
        $arn = $this->sqs->getQueueArn($this->queueUrl);

        return json_encode([
            'Version'   => '2008-10-17',
            'Id'        =>  sprintf('%s/SQSDefaultPolicy', $arn),
            'Statement' => [
                [
                    'Sid'       => 'SNSPermissions',
                    'Effect'    => 'Allow',
                    'Principal' => ['AWS' => '*'],
                    'Action'    => 'SQS:SendMessage',
                    'Resource'  => $arn
                ]
            ]
        ]);
    }