R/recvfile.r

In RBigData/remoter: Remote R: Control a Remote R Session from a Local One

#' recvfile
#' 
#' Transfer file from server to client.
#' 
#' @param file_recv,file_send
#' The file paths (as strings) for the input/sent file and the output/received
#' file.
#' @param verbose
#' Should file transfer information be printed?
#' 
#' @return
#' Returns \code{TRUE} invisibly on successful exit.
#' 
#' @export
recvfile = function(file_send, file_recv, verbose=TRUE)
{
  if (missing(file_send) || !is.string(file_send) || missing(file_recv) || !is.string(file_recv))
  {
    if (iam("local"))
      remoter_client_stop("'file_send' and 'file_recv' must each be a single string")
    
    return(invisible())
  }
  
  if (iam("local"))
    exists = remoter_receive()
  else if (iam("remote"))
  {
    exists = file.exists(file_send)
    remoter_send(exists)
  }
  
  if (!exists)
  {
    if (iam("local"))
    {
      remoter_send(NULL)
      remoter_client_stop("'file_send' does not appear to exist")
    }
    else if (iam("remote"))
      remoter_receive()
    
    return(invisible())
  }
  
  
  socket = getval(socket)
  
  if (iam("local"))
  {
    pbdZMQ::zmq.recvfile(file=file_recv, socket=socket, verbose=verbose)
    remoter_send(NULL)
  }
  else if (iam("remote"))
  {
    pbdZMQ::zmq.sendfile(file=file_send, socket=socket)
    remoter_receive()
  }
  
  invisible(TRUE)
}