src/Core/HttpClients/SyncRestHandler.php
private function checkHTTPMethod($requestParameters){
      $verb = $requestParameters->HttpVerbType;
      if(strcasecmp($verb, CoreConstants::HTTP_POST) == 0){
         return CoreConstants::HTTP_POST;
      } else if(strcasecmp($verb, CoreConstants::HTTP_GET) == 0){
         return CoreConstants::HTTP_GET;
      } else{
         throw new SdkException("Internal Error. Unsupported HTTP Method:" . $verb);
      }
    }
private function checkHTTPMethod($requestParameters){
      $verb = $requestParameters->HttpVerbType;
      if(strcasecmp($verb, CoreConstants::HTTP_POST) == 0){
         return CoreConstants::HTTP_POST;
      } else if(strcasecmp($verb, CoreConstants::HTTP_GET) == 0){
         return CoreConstants::HTTP_GET;
      } else{
         throw new SdkException("Internal Error. Unsupported HTTP Method:" . $verb);
      }
    }
Check The HTTP MEthod from the requestParameters, make sure it is either GET or POST

@param RequestParameters  RequestParameters  The requestParameters for the request
@return String HTTP Method