Update Google Calendar integration

pyproject.toml

@@ -62,6 +62,9 @@ module = [
     "apiai.*",
     "feedparser.*",
     "gitlint.*",
+    "google.auth.*",
+    "google.oauth2.*",
+    "google_auth_oauthlib.*",
     "googleapiclient.*",
     "irc.*",
     "mercurial.*",

zulip/integrations/google/get-google-credentials

@@ -1,46 +1,52 @@
 #!/usr/bin/env python3
-import argparse
 import os
 
-from oauth2client import client, tools
-from oauth2client.file import Storage
+from google.auth.transport.requests import Request
+from google.oauth2.credentials import Credentials
+from google_auth_oauthlib.flow import InstalledAppFlow
 
-flags = argparse.ArgumentParser(parents=[tools.argparser]).parse_args()
-
-# If modifying these scopes, delete your previously saved credentials
-# at zulip/bots/gcal/
-# NOTE: When adding more scopes, add them after the previous one in the same field, with a space
-# seperating them.
-SCOPES = "https://www.googleapis.com/auth/calendar.readonly"
+SCOPES = ["https://www.googleapis.com/auth/calendar.events.readonly"]
+# File containing user's access and refresh tokens for Google application requests.
+# If it does not exist, e.g., first run, it is generated on user authorization.
+TOKENS_FILE = "google-tokens.json"
 # This file contains the information that google uses to figure out which application is requesting
 # this client's data.
 CLIENT_SECRET_FILE = "client_secret.json"  # noqa: S105
-APPLICATION_NAME = "Zulip Calendar Bot"
 HOME_DIR = os.path.expanduser("~")
 
 
-def get_credentials() -> client.Credentials:
-    """Gets valid user credentials from storage.
+def get_credentials() -> Credentials:
+    """
+    Writes google tokens to a json file, using the client secret file (for the OAuth flow),
+    and the refresh token.
+
+    If the tokens file exists and is valid, nothing needs to be done.
+    If the tokens file exists, but the auth token is expired (expiry duration of auth token
+    is 1 hour), the refresh token is used to get a new token.
+    If the tokens file does not exist, or is invalid, the OAuth2 flow is triggered.
 
-    If nothing has been stored, or if the stored credentials are invalid,
-    the OAuth2 flow is completed to obtain the new credentials.
+    The OAuth2 flow needs the client secret file, and requires the user to grant access to
+    the application via a browser authorization page, for the first run.
 
-    Returns:
-        Credentials, the obtained credential.
+    The fetched tokens are written to storage in a json file, for reference by other scripts.
     """
 
-    credential_path = os.path.join(HOME_DIR, "google-credentials.json")
-
-    store = Storage(credential_path)
-    credentials = store.get()
-    if not credentials or credentials.invalid:
-        flow = client.flow_from_clientsecrets(os.path.join(HOME_DIR, CLIENT_SECRET_FILE), SCOPES)
-        flow.user_agent = APPLICATION_NAME
-        # This attempts to open an authorization page in the default web browser, and asks the user
-        # to grant the bot access to their data. If the user grants permission, the run_flow()
-        # function returns new credentials.
-        credentials = tools.run_flow(flow, store, flags)
-        print("Storing credentials to " + credential_path)
+    creds = None
+    tokens_path = os.path.join(HOME_DIR, TOKENS_FILE)
+
+    if os.path.exists(tokens_path):
+        creds = Credentials.from_authorized_user_file(tokens_path, SCOPES)
+    if not creds or not creds.valid:
+        if creds and creds.expired and creds.refresh_token:
+            creds.refresh(Request())
+        else:
+            flow = InstalledAppFlow.from_client_secrets_file(
+                os.path.join(HOME_DIR, CLIENT_SECRET_FILE), SCOPES
+            )
+            creds = flow.run_local_server(port=0)
+        with open(tokens_path, "w") as token:
+            token.write(creds.to_json())
+    return creds
 
 
 get_credentials()

zulip/integrations/google/google-calendar

@@ -1,7 +1,4 @@
 #!/usr/bin/env python3
-#
-# This script depends on python-dateutil and python-pytz for properly handling
-# times and time zones of calendar events.
 import argparse
 import datetime
 import itertools
@@ -12,23 +9,23 @@ import time
 from typing import List, Optional, Set, Tuple
 
 import dateutil.parser
-import httplib2
 import pytz
-from oauth2client import client
-from oauth2client.file import Storage
 
 try:
-    from googleapiclient import discovery
+    from google.oauth2.credentials import Credentials
+    from googleapiclient.discovery import build
 except ImportError:
-    logging.exception("Install google-api-python-client")
+    logging.exception("Install the required python packages from requirements.txt first.")
     sys.exit(1)
 
 sys.path.append(os.path.join(os.path.dirname(__file__), "../../"))
 import zulip
 
-SCOPES = "https://www.googleapis.com/auth/calendar.readonly"
+SCOPES = ["https://www.googleapis.com/auth/calendar.events.readonly"]
+# File containing user's access and refresh tokens for Google application requests.
+# If it does not exist, e.g., first run, it is generated on user authorization.
+TOKENS_FILE = "google-tokens.json"
 CLIENT_SECRET_FILE = "client_secret.json"  # noqa: S105
-APPLICATION_NAME = "Zulip"
 HOME_DIR = os.path.expanduser("~")
 
 # Our cached view of the calendar, updated periodically.
@@ -39,26 +36,20 @@ sent: Set[Tuple[int, datetime.datetime]] = set()
 
 sys.path.append(os.path.dirname(__file__))
 
-parser = zulip.add_default_arguments(
-    argparse.ArgumentParser(
-        r"""
+usage = r"""google-calendar --user EMAIL [--interval MINUTES] [--calendar CALENDAR_ID]
 
-google-calendar --calendar [email protected]
+    This integration can be used to send Zulip messages as reminders for upcoming events from your Google Calendar.
 
-    This integration can be used to send yourself reminders, on Zulip, of Google Calendar Events.
+    Specify your Zulip API credentials and server in a ~/.zuliprc file, or using the options.
 
-    Specify your Zulip API credentials and server in a ~/.zuliprc file or using the options.
+    Before running this integration, make sure you download the client secret file from Google, and run the get-google-credentials script to give Zulip read access to your Google Calendar.
 
-    Before running this integration make sure you run the get-google-credentials file to give Zulip
-    access to certain aspects of your Google Account.
+    This integration should be run on your local machine, as your API key is accessible to local users through the command line.
 
-    This integration should be run on your local machine. Your API key and other information are
-    revealed to local users through the command line.
-
-    Depends on: google-api-python-client
+    For more information, see https://zulip.com/integrations/doc/google-calendar.
 """
-    )
-)
+
+parser = zulip.add_default_arguments(argparse.ArgumentParser(usage=usage))
 
 
 parser.add_argument(
@@ -88,7 +79,7 @@ if not options.zulip_email:
 zulip_client = zulip.init_from_options(options)
 
 
-def get_credentials() -> client.Credentials:
+def get_credentials() -> Credentials:
     """Gets valid user credentials from storage.
 
     If nothing has been stored, or if the stored credentials are invalid,
@@ -99,12 +90,10 @@ def get_credentials() -> client.Credentials:
         Credentials, the obtained credential.
     """
     try:
-        credential_path = os.path.join(HOME_DIR, "google-credentials.json")
-
-        store = Storage(credential_path)
-        return store.get()
-    except client.Error:
-        logging.exception("Error while trying to open the `google-credentials.json` file.")
+        tokens_path = os.path.join(HOME_DIR, TOKENS_FILE)
+        return Credentials.from_authorized_user_file(tokens_path, SCOPES)
+    except ValueError:
+        logging.exception("Error while trying to open the %s file.", TOKENS_FILE)
         sys.exit(1)
     except OSError:
         logging.error("Run the get-google-credentials script from this directory first.")
@@ -113,8 +102,7 @@ def get_credentials() -> client.Credentials:
 
 def populate_events() -> Optional[None]:
     credentials = get_credentials()
-    creds = credentials.authorize(httplib2.Http())
-    service = discovery.build("calendar", "v3", http=creds)
+    service = build("calendar", "v3", credentials=credentials)
 
     now = datetime.datetime.now(pytz.utc).isoformat()
     feed = (
@@ -186,9 +174,7 @@ def send_reminders() -> Optional[None]:
     else:
         message = "Reminder:\n\n" + "\n".join("* " + m for m in messages)
 
-    zulip_client.send_message(
-        dict(type="private", to=options.zulip_email, sender=options.zulip_email, content=message)
-    )
+    zulip_client.send_message({"type": "direct", "to": [options.zulip_email], "content": message})
 
     sent.update(keys)
 

zulip/integrations/google/requirements.txt

@@ -1,2 +1,5 @@
-httplib2>=0.22.0
-oauth2client>=4.1.3
+google-api-python-client>=1.7.9
+google-auth-httplib2>=0.0.3
+google-auth-oauthlib>=0.4.0
+python-dateutil
+pytz