新手提问，我想做一个回声机器人，用的是谷歌apps script，恳求大神帮我看看这代码哪里有问题？还是我哪里操作错了？

[weixin_48211220]

var TOKEN = '我机器人里面的token';
var BASE_URL = 'https://api.sydney.im:8443/' + TOKEN + '/';
function doGet(e) {
const code = {
res: true
}
return ContentService.createTextOutput(JSON.stringify(code))
.setMimeType(ContentService.MimeType.JSON);
}
function doPost(e) {
var bodys = JSON.parse(e.postData.contents);
Logger.log(bodys)
mongo.insert("nowmoer", e)

for (var i = 0; i < bodys.length; i++) {
body = bodys[i];
if (body) {
mongo.insert("nowmoer", body)
payload = preparePayload(body);
toPotato(payload)
}
}
}
function toPotato(payload) {
Logger.log(payload)
if (Array.isArray(payload)) {
payloads = payload;
} else {
payloads = [payload];
}
Logger.log(payloads)
for (var i = 0; i < payloads.length; i++) {
payload = payloads[i];
if (payload) {
var res = postPotato(payload);
Logger.log(res)
}
}
}
function setWebhook() { //绑定setWebhook函数，请运行这个函数
var setWebhook = {
method: 'setWebhook',
payload: {
url: '我填的是我发布网络部署之后的url'
}
}
Logger.log(postPotato(setWebhook))
}
function postPotato(payload) {
var data = {
'contentType': 'application/json',
"method": "post",
"payload": JSON.stringify(payload.payload)
}

var response = UrlFetchApp.fetch(BASE_URL + payload.method, data);
var res = JSON.parse(response);
mongo.insert("nowmoer", res)
return res;
}
function preparePayload(body) {
if (body.message && body.message.text) {
if (body.message.from.id = 21564027) {
return null
}
var sendTextMessage = {
method: 'sendTextMessage',
payload: {
"chat_type": body.message.chat.type,
"chat_id": body.message.chat.id,
"text": mest,
"markdown": true,
}
}
var mest = body.message.text;
if (mest == '小掌门') {
var zhangmeng = ['你好', 'hi',]
sendTextMessage.payload.text = 'zhangmeng'
return sendTextMessage
}
if (mest) {
sendTextMessage.payload.text = mest
return sendTextMessage
}
}
}

[milaoshu1020]

发错地方了?