I can't authorize gmail api application in google colaboratory

Question

I'm running the quickstart code from https://developers.google.com/people/quickstart/python in a colab notebook.

# \[START people_quickstart\]

from __future__ import print_function

import os.path

from google.auth.transport.requests import Request
from google.oauth2.credentials import Credentials
from google_auth_oauthlib.flow import InstalledAppFlow
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError

# If modifying these scopes, delete the file token.json.

SCOPES = \['https://www.googleapis.com/auth/contacts.readonly'\]

def main():
"""Shows basic usage of the People API.
Prints the name of the first 10 connections.
"""
creds = None
\# The file token.json stores the user's access and refresh tokens, and is
\# created automatically when the authorization flow completes for the first
\# time.
if os.path.exists('token.json'):
creds = Credentials.from_authorized_user_file('token.json', SCOPES)
\# If there are no (valid) credentials available, let the user log in.
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(
'credentials.json', SCOPES)
creds = flow.run_local_server(port=0)
\# Save the credentials for the next run
with open('token.json', 'w') as token:
token.write(creds.to_json())

    try:
        service = build('people', 'v1', credentials=creds)
    
        # Call the People API
        print('List 10 connection names')
        results = service.people().connections().list(
            resourceName='people/me',
            pageSize=10,
            personFields='names,emailAddresses').execute()
        connections = results.get('connections', [])
    
        for person in connections:
            names = person.get('names', [])
            if names:
                name = names[0].get('displayName')
                print(name)
    except HttpError as err:
        print(err)

if __name__ == '__main__':
main()

# \[END people_quickstart\]

but it fails the authentication at this stage:

http://localhost:52591/?state=K8nzFjxOrWJkPEqjeG1AZiGpsT5DSx&code=4/0ARtbsJoAH2rD9UYgHOKJ__UdJcq87d2vuFjEAqcI3aKJpj1rLJ-93TXR0_v-LnBR4Fytsg&scope=https://www.googleapis.com/auth/gmail.readonly

why is it redirected to localhost? There is a simple way to send e-mail at google colab? with or without using gmail?

i'm using the google colab at opera browser.

Can anyone help me how i can send a simple e-mail at google colab without lowing the gmail security level?

T.T

Answer 1

today I came across the same problem and the way I found to fix it was running the code in a Jupyter Notebook and then saving the token it was generated there and uploading it to colab.

I ran the code bellow and then a json file named 'token' was generated in the folder where my notebook is located:

import os.path

import google.auth.exceptions
from google.auth.transport.requests import Request
from google.oauth2.credentials import Credentials
from google_auth_oauthlib.flow import InstalledAppFlow
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError

SCOPES = ["https://www.googleapis.com/auth/gmail.send"]

creds = None

if os.path.exists('token.json'):
    try:
        creds = Credentials.from_authorized_user_file('token.json', SCOPES)
        creds.refresh(Request())
    except google.auth.exceptions.RefreshError as error:
        # if refresh token fails, reset creds to none.
        creds = None
        print(f'An error occurred: {error}')
# If there are no (valid) credentials available, let the user log in.
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('credentials.json', SCOPES)
InstalledAppFlow.from_client_secrets_file('credentials_web.json', SCOPES)
        creds = flow.run_local_server(port=0)
    with open('token.json', 'w') as token:
        token.write(creds.to_json())

When this is over just run the same code in colab and make sure you updated the token to the environment and thats it. Not simple, but it works