addCallback for rmote

example.R

my_callback <- function(expr, value, ok, visible) {
  if(inherits(value, "help_files_with_topic")) {
    message("I'm doing one more thing with this help object...")
    # do rmote serving stuff...
    # except the default print method has already been called
    # which if help_type == "text" will defeat the purpose of rmote
    # and if help_type == "html" will result in something like
    # "Error: no display specified" on a headless linux system
  } else if(inherits(value, "htmlwidget")) {
    message("I'm doing one more thing with this htmlwidget...") 
    # do rmote serving stuff...
    # except the default print method has already been called
    # which on a headless linux system will usually return an error like
    # "Error: no display specified"
  } else if(inherits(value, c("trellis", "ggplot2"))) {
    message("I'm doing one more thing with this lattice/ggplot2 object...")
    # do rmote serving stuff...
    # this one works okay although the plot will be printed twice
  }
  TRUE
}

addTaskCallback(my_callback)