Google Drive Python API authorization using service account key

Question

I have the following service account json credentials file for a Google Cloud Platform project:

How would I authenticate to Google Drive API using this service account? For example, when I try doing the following:

from googleapiclient.discovery import build
from httplib2 import Http
from oauth2client import file, client, tools

SCOPES = 'https://www.googleapis.com/auth/drive.metadata.readonly'

flow = client.flow_from_clientsecrets('mykey.json', SCOPES)
creds = tools.run_flow(flow, store)
service = build('drive', 'v3', http=creds.authorize(Http()))

results = service.files().list(pageSize=10, fields="nextPageToken, files(id, name)").execute()
items = results.get('files', [])

I get an error when running the flow command that complains about the format of the keyfile not starting with web or installed:

Invalid file format. See https://developers.google.com/api-client-library/python/guide/aaa_client_secrets
Expected a JSON object with a single property for a "web" or "installed" application

Is there a way to use the above key to list my Drive files for my Google Service Account? If so, how would this be done?

Meir Cohen Meir Cohen · Accepted Answer · 2020-12-31T00:04:31

For using service account credentials, the ServiceAccountCredentials library should be imported from oauth2client.service_account and used as below:

# The needed import for service account credentials:
from oauth2client.service_account import ServiceAccountCredentials

from apiclient.discovery import build

scope = ['https://www.googleapis.com/auth/drive']

# Parsing JSON credentials for a service account:
credentials = ServiceAccountCredentials.from_json_keyfile_name('creds.json', scope)

service = build('drive', 'v3', credentials=credentials)

Then, use service as regular, e.g. service.files() etc.

Google Drive Python API authorization using service account key

2 Answers