upload_tab_controller.R

upload_data <- function(input, output, session){
  dframe <- reactive( {
    #inputfile <- input$infilepower
    validate(
      need(input$infilepower != "","Please select a data set")
    )
    
    dframe <- fread(input$infilepower$datapath, header = TRUE, sep = ",")
    dframe$timestamp <- fastPOSIXct(dframe$timestamp)
    # dframe_xts <- xts(dframe$power,dframe$timestamp)
    dframe
  } )
  
  df <- reactive( {
    dframe <- dframe()
    if (input$specdaterange| input$specdate){
      if(input$specdaterange) {
        start_date = input$seldaterange[1]
        end_date =input$seldaterange[2]
        startdate <- fastPOSIXct(paste0(start_date,' ',"00:00:00"))
        enddate <- fastPOSIXct(paste0(end_date,' ',"23:59:59"))
      } else {
        datex = input$seldate
        startdate <- fastPOSIXct(paste0(datex,' ',"00:00:00"))
        enddate <- fastPOSIXct(paste0(datex,' ',"23:59:59"))
      }
      dframe <- dframe[dframe$timestamp >= startdate & dframe$timestamp <= enddate,] #reduced
    }
    dfs <- dframe
    dfs
  } )
  
  # this function calls df()[it keeps check on time range for displaying] which in turn call dframe[this function loads intially data from file]
  output$lineplt1 <- renderPlotly({
    df_sub <- df()
    colnames(df_sub) <- c("timestamp","Power")
    g <- ggplot(df_sub, aes(timestamp, Power))
    g <- g + geom_line() + labs(x = "", y ="power (Watts)")
    g <- g + scale_x_datetime(labels = date_format("%Y-%d-%b %H:%M",tz="Asia/Kolkata")) # use scales package
    g <- g + theme(axis.text.x = element_text(angle = 45,hjust = 1))
    ggplotly(g)
    #g
  })
}