How do I use google.auth instead of oauth2client in Python to get access to my Google Calendar

Question

Several years ago I created a small Python program which were able to maintain my calendar using oauth2client which is now deprecated and replaced with google.auth - but I cannot find any useful documentation and my program stopped working complaining about a _module KeyError which nobody appear to have solved except by upgrading.

I cannot figure out how to replace the oauth2client with google.auth:

import datetime
import httplib2
import os

from apiclient import discovery
import oauth2client
from oauth2client import client
from oauth2client import tools

...

credentials = get_credentials()
http = credentials.authorize(httplib2.Http())
service = discovery.build('calendar', 'v3', http=http)

Renault

Have you checked this developers.google.com/calendar/quickstart/python? – Semirigid

Are you using a service account or the user credentials? – Disassociate

@AkshayMaldhure: The link still show the obsolete way of doing it! – Renault

@LorenzoPersichetti: User credentials (I think). I log in the first time and get some code which I store in a file which the program use in the future to get access. – Renault

Where does it say so? – Semirigid

@LorenzoPersichetti Yes, I follow a similar way for the Google Sheets API v4. – Semirigid

@AkshayMaldhure look at my answer for deprecation details – Disassociate

Answer 1

According to the oauth2client deprecation notes, the replacement to be used to manage Google user credentials is google-auth-oauthlib. Below a snippet working on my PC (python 3.6).

As the documentation highlights the new library does not save the credentials, that's why I am using pickle to save them. Maybe, depending on your application requirements, you want to have a more robust solution (like a database).

import os
import pickle

from googleapiclient.discovery import build
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request

SCOPES = ['https://www.googleapis.com/auth/calendar.readonly', ]


# we check if the file to store the credentials exists
if not os.path.exists('credentials.dat'):

    flow = InstalledAppFlow.from_client_secrets_file('client_id.json', SCOPES)
    credentials = flow.run_local_server()

    with open('credentials.dat', 'wb') as credentials_dat:
        pickle.dump(credentials, credentials_dat)
else:
    with open('credentials.dat', 'rb') as credentials_dat:
        credentials = pickle.load(credentials_dat)

if credentials.expired:
    credentials.refresh(Request())

calendar_sdk = build('calendar', 'v3', credentials=credentials)

calendars_get_params = {
        'calendarId': 'primary',
    }

test = calendar_sdk.calendars().get(**calendars_get_params).execute()
print(test)

Disassociate

OSError: [Errno 98] Address already in use. What does it mean? I use Service Account client ID. – Livonia

This is not related to my script, but to something that is probably pending on your side. Be sure you don't have previous script runs stuck. – Disassociate

Answer 2

I haven't robustly tested this, but it works for testing snippets with my personal account. I'm sure there are changes that could and/or should be made to it for enterprise applications, such as passing auth'd Http() instances, detecting scope changes, and so on.

You can review the full code on my GitHub repo:

requirements:

• google-api-python-client
• google-auth
• google-auth-oauthlib
• whatever deps the above pull in

I use the InstalledAppFlow class, and generally followed the instructions on Google's Python auth guide.

Code (Python 3.6)

# Google API imports
from googleapiclient.discovery import build
from google.oauth2.credentials import Credentials
from google_auth_oauthlib.flow import InstalledAppFlow

SCOPES = ['your scopes', 'here']

def get_saved_credentials(filename='creds.json'):
    '''Read in any saved OAuth data/tokens
    '''
    fileData = {}
    try:
        with open(filename, 'r') as file:
            fileData: dict = json.load(file)
    except FileNotFoundError:
        return None
    if fileData and 'refresh_token' in fileData and 'client_id' in fileData and 'client_secret' in fileData:
        return Credentials(**fileData)
    return None

def store_creds(credentials, filename='creds.json'):
    if not isinstance(credentials, Credentials):
        return
    fileData = {'refresh_token': credentials.refresh_token,
                'token': credentials.token,
                'client_id': credentials.client_id,
                'client_secret': credentials.client_secret,
                'token_uri': credentials.token_uri}
    with open(filename, 'w') as file:
        json.dump(fileData, file)
    print(f'Credentials serialized to {filename}.')

def get_credentials_via_oauth(filename='client_secret.json', scopes=SCOPES, saveData=True) -> Credentials:
    '''Use data in the given filename to get oauth data
    '''
    iaflow: InstalledAppFlow = InstalledAppFlow.from_client_secrets_file(filename, scopes)
    iaflow.run_local_server()
    if saveData:
        store_creds(iaflow.credentials)
    return iaflow.credentials

def get_service(credentials, service='sheets', version='v4'):
    return build(service, version, credentials=credentials)

Usage is then:

creds = get_saved_credentials()
if not creds:
    creds = get_credentials_via_oauth()
sheets = get_service(creds)

Deserve

OSError: [Errno 98] Address already in use. What does it mean? I use Service Account client ID. – Livonia

@Livonia If you are using service account credentials, you do not need the google.auth.oauthlib helper package - your use case is handled effectively with just google.auth: google-auth.readthedocs.io/en/stable/… Anyway, comments are not where you ask new questions. – Deserve