AppScript for Google Forms to handle onSubmit. Sends form responses to the URL, in this example to the Slack channel hook

onSubmit.gs

// Your Slack webhook url
var webhookUrl = 'https://hooks.slack.com/services/.....';

/**
 * Submit for forms "On form submit" event trigger (add in triggers)
 */
function onSubmit(e) {
  var formTitle = FormApp.getActiveForm().getTitle();
  var formUrl = FormApp.getActiveForm().getEditUrl();
  var response = e.response.getItemResponses();
  const email = e.response.getRespondentEmail()
  var s = "Signup form response from" + email + "\n\n";
  var formResponse = e.response;
  var itemResponses = formResponse.getItemResponses();
  const blocks = []
  for (var j = 0; j < itemResponses.length; j++) {
    var itemResponse = itemResponses[j];
    s += itemResponse.getItem().getTitle() + '\n\n ' + itemResponse.getResponse() + "\n\n"
    blocks.push({
      "type": "section",
      "text": {
        "text": "*" + itemResponse.getItem().getTitle() + "*",
        "type": "mrkdwn"
      },
      "fields": [
        {
          "type": "plain_text",
          "text": "> " + itemResponse.getResponse()
        }
      ]
    })
  }

  var payload = {
    "payload": JSON.stringify({
      "text": s,
      "blocks": [
        {
          "type": "section",
          "text": {
            "type": "mrkdwn",
            "text": "*🚀 <" + formUrl + "|" + formTitle + "> got a response from " + email + "*"
          }
        },
        {
          "type": "divider"
        },
        ...blocks,
        {
          "type": "section",
          "text": {
            "type": "mrkdwn",
            "text": "📅 Submitted " + formResponse.getTimestamp().toUTCString(),
          },
          "accessory": {
            "type": "button",
            "text": {
              "type": "plain_text",
              "text": "Open responses" 
            },
            "value": "click_me_123",
            "url": formUrl + "/edit#responses",
            "action_id": "button-action"
          }
        }
      ]
    })
  }

  var options = {
    "method": "post",
    "payload": payload
  };

  UrlFetchApp.fetch(webhookUrl, options);
};