access Shopware 6 Management API by Apps Scripts

Question

I am trying to access Shopware 6 Management API by this Apps Scripts function: But I get Unsupported Media Type back. I don't understand why as I set the contentType according to here correctly. Has anybody an idea?

function setProductName(){
    let url = CONFIG.url+"/api/product/" + "007f477135584b3c95f9437c4a9fc1ba"
    Logger.log(url)
    var payload = JSON.stringify({
    "data": {
      "name":"API test",
    }
  });

  var auth_token = getAuthenticationToken();
    let options = {
    "method": "GET",
    "contentType": "application/json",
    "headers": {
      "Authorization": "Bearer " + auth_token,
      "Content-Type": "application/json",
    },
    //"payload":payload,
    "muteHttpExceptions": false
  };
  req = UrlFetchApp.getRequest(url, options)
  Logger.log(req)
  let response = UrlFetchApp.fetch(url, options);
  let responseData = JSON.parse(response.getContentText());
  Logger.log(responseData)

  return responseData;
}

Answer 1

After some hours of searching, I found that the solution is to set the Accept Header too:

"headers": {
  "Accept":"application/json",
  "Authorization": "Bearer " + auth_token
},