Bookmarking and saving the bookmarks in R shiny

Question

I am trying to use the bookmark in R shiny app and the save the bookmarks in a table. First stage I want to save them locally and retrieve them whenever I load this applicat

Answer 1

Here is an alternative approach to my earlier answer using saveRDS() instead of sqlite:

Edit: Added username check.

library(shiny)
# library(RSQLite)
library(data.table)

ui <- function(request) {
  fluidPage(
    plotOutput("plot"),
    sliderInput("n", "Number of observations", 1, nrow(faithful), 100),
    fluidRow(column(2, textInput(inputId = "description", label = "Bookmark description", placeholder = "Data Summary")), column(2, bookmarkButton(id="bookmarkBtn"))),
    DT::dataTableOutput("urlTable", width = "100%"),
    tags$style(type='text/css', "#bookmarkBtn { width:100%; margin-top: 25px;}")
  )
}

server <- function(input, output, session) {

  # con <- dbConnect(RSQLite::SQLite(), "bookmarks.db", overwrite = FALSE)
  myBookmarks <- reactiveValues(urlDF = NULL)

  observeEvent(input$bookmarkBtn, {
    session$doBookmark()
  })

  # if(dbExistsTable(con, "Bookmarks")){
  #   tmpUrlDF <- data.table(dbReadTable(con, "Bookmarks"))
  #   myBookmarks$urlDF <- tmpUrlDF[, Timestamp := as.POSIXct(Timestamp, origin="1970-01-01 00:00")]
  # } else {
  #   myBookmarks$urlDF <- NULL
  # }

  if(file.exists("bookmarks.rds")){
    myBookmarks$urlDF <- readRDS("bookmarks.rds")
  } else {
    myBookmarks$urlDF <- NULL
  }

  session$onSessionEnded(function() {
    tmpUrlDF <- isolate({myBookmarks$urlDF})
    if(!is.null(tmpUrlDF)){
      # dbWriteTable(con, "Bookmarks", tmpUrlDF, overwrite = TRUE)
      saveRDS(tmpUrlDF, "bookmarks.rds")
    }
    # dbDisconnect(con)
  })

  setBookmarkExclude(c("bookmarkBtn", "description", "urlTable_cell_clicked", "urlTable_rows_all", "urlTable_rows_current", "urlTable_rows_selected", "urlTable_search", "urlTable_state", "urlTable_row_last_clicked"))

  output$plot <- renderPlot({
    hist(faithful$eruptions[seq_len(input$n)], breaks = 40)
  })

  onBookmarked(fun=function(url){
    if(!url %in% myBookmarks$urlDF$URL){
      if(is.null(myBookmarks$urlDF)){
        myBookmarks$urlDF <- unique(data.table(Description = input$description, URL = paste0("", url,""), Timestamp = Sys.time(), Session = session$token, User = Sys.getenv("USERNAME")), by="URL")
      } else {
        myBookmarks$urlDF <- unique(rbindlist(list(myBookmarks$urlDF, data.table(Description = input$description, URL = paste0("", url,""), Timestamp = Sys.time(), Session = session$token, User = Sys.getenv("USERNAME")))), by="URL")
      }
    }
  })

  output$urlTable = DT::renderDataTable({
  req(myBookmarks$urlDF)
    myBookmarks$urlDF[User %in% Sys.getenv("USERNAME")]
  }, escape=FALSE)

}

enableBookmarking(store = "url")
shinyApp(ui, server)