how to automatically download Google spreadsheet data using Google Apps script

Question

I am a newbie in using Google Apps scripts. I was wondering if i could create a backup program which automatically downloads the spreadsheet data in a csv file after 15 minutes of every change. Do i have to create some kind of cronjob? I have created a following script which reads all the data from the current sheet and create a csv file.

/**
 * Adds a custom menu to the active spreadsheet, containing a single menu item
 * for invoking the readRows() function specified above.
 * The onOpen() function, when defined, is automatically invoked whenever the
 * spreadsheet is opened.
 * For more information on using the Spreadsheet API, see
 * https://developers.google.com/apps-script/service_spreadsheet
 */
function onOpen() {
  var sheet = SpreadsheetApp.getActiveSpreadsheet();
  var entries = [{
    name : "Download Data",
    functionName : "saveAsCSV"
  }];
  sheet.addMenu("Script Center Menu", entries);
};

function saveAsCSV() {
  // Prompts the user for the file name
  var fileName = Browser.inputBox("Save CSV file as (e.g. myCSVFile):");

  // Check that the file name entered wasn't empty
  if (fileName.length !== 0) {
    // Add the ".csv" extension to the file name
    fileName = fileName + ".csv";
    // Convert the range data to CSV format
    var csvFile = convertRangeToCsvFile_(fileName);
    // Create a file in the Docs List with the given name and the CSV data
    DocsList.createFile(fileName, csvFile);
  }
  else {
    Browser.msgBox("Error: Please enter a CSV file name.");
  }
}

function convertRangeToCsvFile_(csvFileName) {
  try {
    var csvFile = undefined;

    var sheet = SpreadsheetApp.getActiveSheet();
    var rows = sheet.getDataRange();
    var numRows = rows.getNumRows();
    var data = rows.getValues();

    // Loop through the data in the range and build a string with the CSV data
    if (data.length > 1) {
      var csv = "";
      for (var row = 0; row < data.length; row++) {
        for (var col = 0; col < data[row].length; col++) {
          if (data[row][col].toString().indexOf(",") != -1) {
            data[row][col] = "\"" + data[row][col] + "\"";
          }
        }

        // Join each row's columns
        // Add a carriage return to end of each row, except for the last one
        if (row < data.length-1) {
          csv += data[row].join(",") + "\r\n";
        }
        else {
          csv += data[row];
        }
      }
      csvFile = csv;
    }
    return csvFile;
  }
  catch(err) {
    Logger.log(err);
    Browser.msgBox(err);
  }
}

I want to run this script on a regular interval. What do i have to do for this?

Answer 1

The code will be the same. Use just have to add a trigger on the spreadsheet. Just go to Script Editor -> Resources -> All your triggers and add a new trigger, make it time-driven and select interval and it is done. :)

function saveAsCSV() {
  // Prompts the user for the file name
  var fileName = SpreadsheetApp.getActiveSheet().getSheetName();

  // Check that the file name entered wasn't empty
  if (fileName.length !== 0) {
    // Add the ".csv" extension to the file name
    fileName = fileName + ".csv";

    // Convert the range data to CSV format
    var csvFile = convertRangeToCsvFile_(fileName);
    // Create a file in the Docs List with the given name and the CSV data
    DocsList.createFile(fileName, csvFile);
  }
  else {
    Browser.msgBox("Error: Please enter a CSV file name.");
  }
}

function convertRangeToCsvFile_(csvFileName) {
  try {
    var csvFile = undefined;

    var ss = SpreadsheetApp.getActiveSpreadsheet();
    var sheet = ss.getSheets()[10];
    var rows = sheet.getDataRange();
    var numRows = rows.getNumRows();
    var data = rows.getValues();

    // Loop through the data in the range and build a string with the CSV data
    if (data.length > 1) {
      var csv = "";
      for (var row = 0; row < data.length; row++) {
        for (var col = 0; col < data[row].length; col++) {
          if (data[row][col].toString().indexOf(",") != -1) {
            data[row][col] = "\"" + data[row][col] + "\"";
          }
        }

        // Join each row's columns
        // Add a carriage return to end of each row, except for the last one
        if (row < data.length-1) {
          csv += data[row].join(",") + "\r\n";
        }
        else {
          csv += data[row];
        }
      }
      csvFile = csv;
    }
    return csvFile;
  }
  catch(err) {
    Logger.log(err);
    Browser.msgBox(err);
  }
}