hubot google calendar integration how to send message from google calendar api to chat?

I want to send message that was got from google calendar api.

my codes are below. hubot/gcal.coffee and hubot/scripts/example-gcal.coffee

I want to create message string in hubot/gcal.coffee, and send message to chat in hubot/scripts/example-gcal.coffee

gcal.coffee is created along with google’s node.js quickstart (https://developers.google.com/google-apps/calendar/quickstart/nodejs).
gcal.coffee can get response from google calendar api but I cannot send response to chat.

I wonder gcal.coffee get response asynchronously so I should recieve after that but I cannot solve it.

Where should I change ?

hubot/gcal.coffee

fs = require('fs')
readline = require('readline')
google = require('googleapis')
googleAuth = require('google-auth-library')
# If modifying these scopes, delete your previously saved credentials
# at ~/.credentials/calendar-nodejs-quickstart.json
SCOPES = [ 'https://www.googleapis.com/auth/calendar.readonly' ]
TOKEN_DIR = (process.env.HOME or process.env.HOMEPATH or process.env.USERPROFILE) + '/.credintials/'
TOKEN_PATH = TOKEN_DIR + 'calendar-nodejs-quickstart.json'
class Gcal
  CLIENT_SECRET_FILE = 'client_secret.json'
  constructor : () ->
# Load client secrets from a local file.
  get10Schedule: () ->
    fs.readFile CLIENT_SECRET_FILE, (err, content) ->
      if err
        console.log 'Error loading client secret file: ' + err
        return
      # Authorize a client with the loaded credentials, then call the
      # Google Calendar API.
      authorize JSON.parse(content), listEvents
      return
  ###*
  # Create an OAuth2 client with the given credentials, and then execute the
  # given callback function.
  #
  # @param {Object} credentials The authorization client credentials.
  # @param {function} callback The callback to call with the authorized client.
  ###
  authorize = (credentials, callback) ->
    clientSecret = credentials.installed.client_secret
    clientId = credentials.installed.client_id
    redirectUrl = credentials.installed.redirect_uris[0]
    auth = new googleAuth
    oauth2Client = new (auth.OAuth2)(clientId, clientSecret, redirectUrl)
    # Check if we have previously stored a token.
    fs.readFile TOKEN_PATH, (err, token) ->
      if err
        getNewToken oauth2Client, callback
      else
        oauth2Client.credentials = JSON.parse(token)
        callback oauth2Client
      return
    return
  ###*
  # Get and store new token after prompting for user authorization, and then
  # execute the given callback with the authorized OAuth2 client.
  #
  # @param {google.auth.OAuth2} oauth2Client The OAuth2 client to get token for.
  # @param {getEventsCallback} callback The callback to call with the authorized
  #     client.
  ###
  getNewToken = (oauth2Client, callback) ->
    authUrl = oauth2Client.generateAuthUrl(
      access_type: 'offline'
      scope: SCOPES)
    console.log 'Authorize this app by visiting this url: ', authUrl
    rl = readline.createInterface(
      input: process.stdin
      output: process.stdout)
    rl.question 'Enter the code from that page here: ', (code) ->
      rl.close()
      oauth2Client.getToken code, (err, token) ->
        if err
          console.log 'Error while trying to retreive access token', err
          return
        oauth2Client.credentials = token
        storeToken token
        callback oauth2Client
        return
      return
    return
  ###*
  # Store token to disk be used in later program executions.
  #
  # @param {Object} token The token to store to disk.
  ###
  storeToken = (token) ->
    try
      fs.mkdirSync TOKEN_DIR
    catch err
      if err.code != 'EEXIST'
        throw err
    fs.writeFile TOKEN_PATH, JSON.stringify(token)
    console.log 'Token stored to ' + TOKEN_PATH
    return
  ###*
  # Lists the next 10 events on the user's primary calendar.
  #
  # @param {google.auth.OAuth2} auth An authorized OAuth2 client.
  ###
  listEvents = (auth) ->
    calendar = google.calendar('v3')
    calendar.events.list {
      auth: auth
      calendarId: 'primary'
      timeMin: (new Date).toISOString()
      maxResults: 10
      singleEvents: true
      orderBy: 'startTime'
    }, (err, response) ->
      if err
        console.log 'The API returned an error: ' + err
        return
      events = response.items
      if events.length == 0
        console.log 'No upcoming events found.'
      else
#        console.log 'Upcoming 10 events: '
        i = 0
        msgs = []
        while i < events.length
          event = events[i]
          start = event.start.dateTime or event.start.date
          #          console.log '%s - %s', start, event.summary
          msg = "#{start} - #{event.summary}"
          msgs.push msg
          i++
#        console.log msgs
      return msgs
    return
module.exports = Gcal

hubot/scripts/example-gcal.coffee

Gcal = require('../gcal.coffee')
module.exports = (robot) ->
  robot.hear /show schedule plz/i, (msg) ->
    gcal = new Gcal()
    schedule = gcal.get10Schedule()
    console.log "schedule is #{schedule}"
    msg = "this is your schedule: #{schedule}"
    robot.send msg

via rootpetit