Example implementation of webhook on Google Apps Script for LINE Simple Beacon with LINE Messaging API

line-beacon-demo.gs

const ACCESS_TOKEN = PropertiesService.getScriptProperties().getProperty('ACCESS_TOKEN');
const urlBase = 'https://api.line.me/v2/bot/';
const myId = PropertiesService.getScriptProperties().getProperty('MY_ID');

function doPost(e) {
  const replyToken = JSON.parse(e.postData.contents).events[0].replyToken;
  const beaconType = JSON.parse(e.postData.contents).events[0].beacon.type;
  const userId = JSON.parse(e.postData.contents).events[0].source.userId;
  const replyUrl = urlBase + 'message/reply';
  
  const displayName = getDisplayName(userId);
  
  myMessage = displayName + 'さんが' + beaconType + 'しました';
  pushMessage(myId, myMessage);

  UrlFetchApp.fetch(replyUrl, {
    'headers': {
      'Content-Type': 'application/json; charset=UTF-8',
      'Authorization': 'Bearer ' + ACCESS_TOKEN,
    },
    'method': 'post',
    'payload': JSON.stringify({
      'replyToken': replyToken,
      'messages': [{
        'type': 'text',
        'text': displayName + 'さんが' + beaconType + 'しました',
      }],
    }),
  });
  return ContentService.createTextOutput(JSON.stringify({'content': 'post ok'})).setMimeType(ContentService.MimeType.JSON);
}

function getUserProfile(userId) {
  const profileUrl = urlBase + 'profile/' + userId;
  let response = UrlFetchApp.fetch(profileUrl, {
    'headers': {
      'Authorization': 'Bearer ' + ACCESS_TOKEN,
    },
    'method': 'get',
  });
  return response.getContentText();
}

function getDisplayName(userId) {
  const userProfile = JSON.parse(getUserProfile(userId));
  return userProfile.displayName;
}

function pushMessage(userId, message){
  const pushUrl = urlBase + 'message/push';

  UrlFetchApp.fetch(pushUrl, {
    'headers': {
      'Content-Type': 'application/json; charset=UTF-8',
      'Authorization': 'Bearer ' + ACCESS_TOKEN,
    },
    'method': 'post',
    'payload': JSON.stringify({
      'to': userId,
      'messages':[{
        'type': 'text',
        'text': message,
      }]
    }),
  });
}