google-apps-script-contact-form.js

var SHEET_NAME = "Sheet1";    //  Enter sheet name where data is to be written
var inputFields = ["nombre", "email", "comentarios"];
var SCRIPT_PROP = PropertiesService.getScriptProperties();
function doRequest(e) {
  var lock = LockService.getPublicLock();
  lock.waitLock(30000);  // wait 30 seconds before conceding defeat.
  try {
    var doc = SpreadsheetApp.openById(SCRIPT_PROP.getProperty("key"));
    var sheet = doc.getSheetByName(SHEET_NAME);
    var lastColumn = sheet.getLastColumn();
    if(lastColumn==0){
      sheet.getRange(1, 1, 1,inputFields.length).setValues([inputFields]);
    }
    var headers = sheet.getRange(1, 1, 1, sheet.getLastColumn()).getValues()[0]; //getRange(row, column, numRows, numColumns)    
    var nextRow = sheet.getLastRow()+1;
    var row = []; 
    for (i in headers){
        if (headers[i] == "Timestamp"){ // special case if you include a 'Timestamp' column
          row.push(new Date());
        } else {
          if(headers[i]){
            row.push(e.parameter[headers[i]]);
          }
        }
    }
    sheet.getRange(nextRow, 1, 1, row.length).setValues([row]);
    return HtmlService.createHtmlOutput(JSON.stringify({"result":"success", "data": e}));
  } catch(e){
    return ContentService
    .createTextOutput(JSON.stringify({"result":"error", "error": e}))
    .setMimeType(ContentService.MimeType.JSON);
  } finally {
    lock.releaseLock();
  }
}
function doPost(e){return doRequest(e);}
function doGet(e){return doRequest(e);}
function setup() {
  var doc = SpreadsheetApp.getActiveSpreadsheet();
  SCRIPT_PROP.setProperty("key", doc.getId());
}

function testSheetsWrite() {
   var doc = SpreadsheetApp.openById(SCRIPT_PROP.getProperty("key"));
    var sheet = doc.getSheetByName(SHEET_NAME);
    var lastColumn = sheet.getLastColumn();
    if(lastColumn==0){
      sheet.getRange(1, 1, 1,inputFields.length).setValues([inputFields]);
    }
}