protected function payload(StructureShape $member, array $value, array &$opts)
 {
     $opts['headers']['Content-Type'] = $this->contentType;
     $opts['body'] = (string) $this->jsonFormatter->build($member, $value);
 }
 /**
  * When invoked with an AWS command, returns a serialization array
  * containing "method", "uri", "headers", and "body" key value pairs.
  *
  * @param CommandInterface $command
  *
  * @return RequestInterface
  */
 public function __invoke(CommandInterface $command)
 {
     $name = $command->getName();
     $operation = $this->api->getOperation($name);
     return new Request($operation['http']['method'], $this->endpoint, ['X-Amz-Target' => $this->api->getMetadata('targetPrefix') . '.' . $name, 'Content-Type' => $this->contentType], $this->jsonFormatter->build($operation->getInput(), $command->toArray()));
 }