function doGet(e) {

var ss = SpreadsheetApp.openById(e.parameter.SHEETID);
var sh = ss.getSheetByName(e.parameter.SHEETNAME);
var rg = sh.getDataRange().getValues();


  //READ ALL RECORDS
  if ( e.parameter.FN == "ReadAll" ) {
    return ContentService.createTextOutput(JSON.stringify(rg)).setMimeType(ContentService.MimeType.JSON);
  }

  //READ SINGLE RECORD
   else if ( e.parameter.FN == "ReadRecord" ) {
    var ref = sh.getRange(parseInt(e.parameter.ROWID)+1,1,1,rg[0].length).getValues();
    return ContentService.createTextOutput(JSON.stringify(ref)).setMimeType(ContentService.MimeType.JSON);
  }
  
  //DELETE SINGLE RECORD
   else if ( e.parameter.FN == "Delete" ) {
    sh.deleteRow(parseInt(e.parameter.ROWID) + 1);  
    return ContentService.createTextOutput("Record Deleted");  
 } 

  //UPDATE SINGLE RECORD
   else if ( e.parameter.FN == "Update" ) { 
    var data = JSON.parse('[' + e.parameter.DATA + ']');
    sh.getRange(parseInt(e.parameter.ROWID) + 1,1,1,data[0].length).setValues(data);
    return ContentService.createTextOutput("Record Updated");
  }

  //CREATE NEW RECORD  
  else if ( e.parameter.FN == "Create" ) { 
    var data = JSON.parse(e.parameter.DATA);
    sh.appendRow(data);
    return ContentService.createTextOutput("New Record Appended");
  }

}