Proof-of-concept web-based joining of Hangouts conversations, using Flask and hangups. Warning: in its current state, allows any user to be invited to any conversation available to the hangups user.

WebJoinHangouts.py

import asyncio
import os
import shlex
from threading import Thread
import time

from emoji import emojize
from flask import Flask, redirect, render_template, request, session, url_for
import hangups
from hangups import hangouts_pb2
from oauth2client.contrib.flask_util import UserOAuth2


class HangupsThread(Thread):

    def __init__(self):
        super(HangupsThread, self).__init__(daemon=True)
        self.loop = asyncio.get_event_loop()
        self.client = hangups.Client(hangups.auth.get_auth_stdin("data/hangups_token.txt"))
        self.ready = False

    def run(self):
        asyncio.set_event_loop(self.loop)
        self.client.on_connect.add_observer(self.on_connect)
        self.client.on_reconnect.add_observer(self.on_connect)
        self.client.on_disconnect.add_observer(self.on_disconnect)
        print("[hangups] Connecting...")
        self.loop.run_until_complete(self.client.connect())

    def on_connect(self):
        print("[hangups] Connected!")
        asyncio.async(self.get_users_chats())

    def on_disconnect(self):
        print("[hangups] Disconnected. Retry in 5 seconds.")
        self.ready = False
        time.sleep(5)
        print("[hangups] Reconnecting...")
        self.loop.run_until_complete(self.client.connect())

    @asyncio.coroutine
    def get_users_chats(self):
        print("[hangups] Fetching users and chats...")
        self.users, self.chats = yield from hangups.conversation.build_user_conversation_list(self.client)
        print("[hangups] Got users and chats.")
        self.chats.on_event.add_observer(self.on_event)
        self.ready = True

    def on_event(self, event):
        print("[hangups] Conversation got a {0}.".format(type(event).__name__))
        if isinstance(event, hangups.ChatMessageEvent):
            print("[hangups] Received text message:")
            print(event.text)
            print("-- EOF --")
            self.parse_message(event.timestamp, event.user_id, event.conversation_id, event.text)

    def parse_message(self, timestamp, user, chat, msg):
        pass

    @asyncio.coroutine
    def invite_to_hangout(self, user, chat):
        event_request_header = hangouts_pb2.EventRequestHeader(conversation_id=hangouts_pb2.ConversationId(id=chat),
                                                               client_generated_id=self.client.get_client_generated_id(),
                                                               expected_otr=hangouts_pb2.OFF_THE_RECORD_STATUS_ON_THE_RECORD)
        request = hangouts_pb2.AddUserRequest(request_header=self.client.get_request_header(),
                                              invitee_id=[hangouts_pb2.InviteeID(gaia_id=user)],
                                              event_request_header=event_request_header)
        print("[hangups] Inviting {0} to {1}.".format(user, chat))
        yield from self.client.add_user(request)
        print("[hangups] Invite sent.")

    @asyncio.coroutine
    def send_message(self, chat, msg):
        message_content = hangouts_pb2.MessageContent(segment=[hangups.ChatMessageSegment(msg).serialize()])
        event_request_header = hangouts_pb2.EventRequestHeader(conversation_id=hangouts_pb2.ConversationId(id=chat),
                                                               client_generated_id=self.client.get_client_generated_id())
        request = hangouts_pb2.SendChatMessageRequest(request_header=self.client.get_request_header(),
                                                      message_content=message_content,
                                                      event_request_header=event_request_header)
        print("[hangups] Sending message to {0}:".format(chat))
        print(msg)
        print("-- EOF --")
        yield from self.client.send_chat_message(request)
        print("[hangups] Message sent.")


app = Flask(__name__)
app.debug = True
app.secret_key = os.urandom(24)
app.config["GOOGLE_OAUTH2_CLIENT_SECRETS_FILE"] = "data/client_secrets.json"

oauth = UserOAuth2(app, access_type="online")

hup = HangupsThread()
hup.start()


@app.route("/")
def index():
    return render_template("index.jinja2", creds=oauth.credentials)

@app.route("/login")
def login():
    return redirect(oauth.authorize_url("/"))

@app.route("/logout")
def logout():
    session.clear()
    return redirect(url_for("index"))

@app.route("/join/<chat>")
@oauth.required
def join(chat):
    if hup.ready:
        asyncio.async(hup.invite_to_hangout(oauth.credentials.id_token["sub"], chat))
        asyncio.async(hup.send_message(chat, emojize(":raising_hand: Invited {0} from website." \
                                                     .format(oauth.credentials.id_token["email"]), use_aliases=True)))
    return render_template("join.jinja2", success=hup.ready)