Xero Google Script Integration

xero-google-script.gs

// Got the code from https://github.com/csi-lk/google-app-script-xero-api

var API_END_POINT = 'https://api.xero.com/api.xro/2.0';
var INVOICES_END_POINT = '/Invoices';

// Working method to send a request with a payload
function sendRequest(endpoint, method, payload) {
  var url = 'https://api.xero.com/api.xro/2.0' + endpoint
  var authHeader = getAuthHeader(method, url);
  var headers = {
    "Authorization": authHeader,
    "Accept": "application/json"
  };
  var options = {
    "headers": headers,
    'method' : method,
    'payload' : payload,
    'muteHttpExceptions': true,
  };

  Logger.log(authHeader);

  var response = UrlFetchApp.fetch(url, options);
  return response;
}

// Receive Sales Invoices
function receiveSalesInvoices() {
  var salesInvoives = receiveInvoices("Statuses=Paid"); // Works
  // var salesInvoives = receiveInvoices("Statuses=Paid,Draft"); // Does not work
  // var salesInvoives = receiveInvoices("where=AccountCode==201"); // Does not work
  
  // Does not work
  //var whereComponent = encodeURIComponent("accountcode=200");
  //var salesInvoices = receiveInvoices("where="+whereComponent);
  
  return salesInvoives;
}

// Receive Invoices
function receiveInvoices(query) {
  var method = 'GET';
  // If query is used then it fails, as the request is not signed properly
  var oauth_nonce = createGuid();
  var oauth_timestamp = (new Date().valueOf()/1000).toFixed(0);
  var url = API_END_POINT+'/Invoices';

  var authHeader = getAuthHeader(method, url, query);
  var headers = {
    "Authorization": authHeader,
    "Accept": "application/json"
  };
  var options = {
    "headers": headers,
    'method' : method,
//    'payload' : JSON.stringify(data),
    'muteHttpExceptions': true,
  };

  if (query) {
    url += "?"+query;
  }

  var response = UrlFetchApp.fetch(url, options);
  var responseXml = response.getContentText();
  var responseArray = JSON.parse(responseXml);
  return responseArray;
}

function createGuid() {
  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
    var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
    return v.toString(16)
      });
}