gistfile1.txt

/* Global Constants */
var cID = 0, cURL = 1, cName = 2, cContact = 3, cChanged=4, cChecksum=5, cMirrorPage=6; // column indices
var baseSiteUrl = 'https://sites.google.com/site/smelendeznicarmirror/'; // site to store mirrored content
var site = SitesApp.getSiteByUrl(baseSiteUrl);
var today = Date();

function test() {
 var sheet = SpreadsheetApp.getActiveSpreadsheet(); 
 GmailApp.sendEmail("smelendez@gmail.com","", sheet.getUrl());
}
/**
 * Downloads the content and checks whether it's changed,
 * sending an email if it has
 * and updating the row and, optionally, mirror page
 */

function processRow(rowValues) {  
  var url = rowValues[cURL];
  var name = rowValues[cName];
  var rowID = rowValues[cID];
  if (!url)
  {
    // Not much we can do here
    return rowValues;
  }
  var response = UrlFetchApp.fetch(url);
  var oldChecksum = rowValues[cChecksum];
  var contentText = response.getContentText(), content = response.getContent();
  var newChecksum = String(Utilities.computeDigest(Utilities.DigestAlgorithm.MD5, contentText));
 
  
  if (newChecksum != oldChecksum)
  {
    // File has changed
    
    var mirrorPageUrl = rowValues[cMirrorPage];
    var page;
    var contacts = rowValues[cContact];
    if (!mirrorPageUrl) {
      // Need to make a mirror page
       page = site.createFileCabinetPage(name, rowID, "");
       rowValues[cMirrorPage] = mirrorPageUrl = page.getUrl();
    }
    else page = SitesApp.getPageByUrl(mirrorPageUrl);
    
    page.addHostedAttachment(Utilities.newBlob(content, "application/octet-stream", url + ' ' + today),  today); // Add it to the site as an attachment
    
    rowValues[cChanged] = today;
    rowValues[cChecksum] = newChecksum;
    
    
    if (contacts)
    {
      // Email the appropriate people
      
      GmailApp.sendEmail(contacts, "Change notification " + url, "See the latest version at " + mirrorPageUrl);
    }
      
    
  }
  return rowValues;
  
}

function processRows() {
  var sheet = SpreadsheetApp.getActiveSheet();
  var rows = sheet.getDataRange();
  var numRows = rows.getNumRows();
  var values = rows.getValues();
  
  var colnames = values[0];
  
  newvalues = [colnames];

  for (var i = 1; i <= numRows - 1; i++) {
    var row = values[i];
    row = processRow(row);
    newvalues.push(row);
  }
  
  // Update with new values
  rows.setValues(newvalues);
  
};

/**
 * 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 : "Process All Rows",
    functionName : "readRows"
  }, ];
  sheet.addMenu("Mirror Tool", entries);
};