UrlFetch with custom user-agent string?

Question

Is it possible to change the user-agent string used with Google Apps Script UrlFetchApp.fetch requests?

This discussion from 2010 insinuates that the UrlFetch module in Google Apps Script supports adding the User-Agent header to the optional headers collection, like the UrlFetch module of Google App Engine does. However, the GAS documentation states nothing about this. A test script I made also shows it doesn't work.

Test script:

function testUserAgentString(){
  var page;
  try {
    page = UrlFetchApp.fetch('http://www.myuseragent.net/',
        {headers: {"User-Agent":
            "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.8.1.6) Gecko/20070725 Firefox/2.0.0.6"
        }}).getContentText();
    Logger.log(page);
  } catch(_) {}
}

Log output (minus irrelevant HTML) was:

Mozilla/5.0 (compatible; GoogleDocs; script; +http://docs.google.com)

which is the default user-agent string used when doing UrlFetch requests by GAS.

Am I missing something or doing something wrong?

Edit: As this is currently not possible, I placed an enhancement request on the Issue Tracker, per Arun's suggestion.

Answer 1

This is not possible today. Please log an enhancement request on the Issue Tracker with your use cases so this can be reviewed and considered.

Answer 2

You can send header information with UrlFetchApp in this way:

var url = "http://mymagentohost/api/rest/products?limit=2"

var params = { 
  headers: { 'Content-Type': "application/json", 'Accept': "application/json",
             'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36'},
  muteHttpExceptions: true,
  method: "GET",
  contentType: "application/json",
  validateHttpsCertificates: false,
};

var response = UrlFetchApp.fetch(url, params);

Just add the user agent information in the headers section. Hope it helps!

Credit goes out to: Aditya Advani