R/updateStatus.R

In Rfacebook: Access to Facebook API via R

#' @rdname updateStatus
#' @export
#'
#' @title 
#' Update Facebook status from R
#'
#' @description
#' \code{updateStatus} sends a status update that will be displayed
#' on the Facebook profile of the authenticated user.
#'
#' @author
#' Pablo Barbera \email{pablo.barbera@@nyu.edu}, Zakharov Kyrylo 
#' (\url{https://github.com/Amice13})
#'
#' @seealso \code{\link{getUsers}}, \code{\link{getPost}}
#'
#' @param text string, text of the status update
#'
#' @param link string, URL of link to be added to status update
#' 
#' @param token Either a temporary access token created at
#' \url{https://developers.facebook.com/tools/explorer} or the OAuth token 
#' created with \code{fbOAuth}. It needs to have extended permissions in order 
#' to successfully post to the Facebook profile.
#'
#' @examples \dontrun{
#' ## See examples for fbOAuth to know how token was created.
#'  load("fb_oauth")
#'  updateStatus("this is just a test", token=fb_oauth)
#' }
#'

updateStatus <- function(text, token, link=NULL) {
  ## text prepocessing
  text <- enc2utf8(text)
  text <- gsub(" ", "+",text)
  
  ## query including text
  query <- paste('https://graph.facebook.com/me/feed?message=', text, sep="")
  ## adding URL
  if (!is.null(link)){
    query <- paste(query, "&link=", link, sep="")
  }
  ## making query
  if (class(token)[1]=="config"){
    url.data <- POST(query, config=token)
  }
  if (class(token)[1]=="Token2.0"){
    url.data <- POST(query, config(token=token))
  }  
  if (class(token)[1]=="character"){
    url <- paste0(query, "&access_token=", token)
    url.data <- POST(url)
  }
  if (class(token)[1]!="character" & class(token)[1]!="config" & class(token)[1]!="Token2.0") {
    stop("Error in access token. See help for details.")
  }
  ## output
  if (url.data$status_code==200){
    id <- fromJSON(rawToChar(url.data$content))$id
    if (is.null(id)){
      message("Failed update. OAuth token does not have permission to update status. ",
              "See ?fbOAuth for more details.")
    }
    message("Success! Link to status update: ", paste("http://www.facebook.com/", id, sep=""))
  }
  if (url.data$status_code==400){
    error <- fromJSON(rawToChar(url.data$content))$error$code
    message <- fromJSON(rawToChar(url.data$content))$error$message
    if (error==2500){
      message("Failed update. OAuth token does not have permission to update status. ",
              "See ?fbOAuth for more details.")
    }
    if (error!=2500){
      message("Failed update.", message)
    }
  }
}