Question

What possible ways to import google contacts using python and oauth2.0 exists?

We successfully got credentials, and our application requests access to contacts, but after getting credentials I can’t find way to discover contacts api.

So things like:

 from apiclient.discover import build
 import httplib2
 http = httplib2.Http()
 #Authorization
 service = build("contacts", "v3", http=http) 

Gives us UnknownApiNameOrVersion exception.
It looks like Contacts API not in list of supported APIs for apiclient.

I’m looking for alternative ways.

Answer 1

The Google Contacts API can’t be used with the google-api-python-client library because it is a Google Data API, while google-api-python-client is intended to be used with discovery-based APIs.

Rather than going through all the trouble described by @NikolayFominyh, you can use the native support for OAuth 2.0 in gdata-python-client.

To get a valid token, follow the instructions from a Google Developers blog post for an in-depth description of the process.

First, create a token object:

import gdata.gauth

CLIENT_ID = 'bogus.id'  # Provided in the APIs console
CLIENT_SECRET = 'SeCr3Tv4lu3'  # Provided in the APIs console
SCOPE = 'https://www.google.com/m8/feeds'
USER_AGENT = 'dummy-sample'

auth_token = gdata.gauth.OAuth2Token(
    client_id=CLIENT_ID, client_secret=CLIENT_SECRET,
    scope=SCOPE, user_agent=USER_AGENT)

Then, authorize your application with this token:

APPLICATION_REDIRECT_URI = 'http://www.example.com/oauth2callback'
authorize_url = auth_token.generate_authorize_url(
    redirect_uri=APPLICATION_REDIRECT_URI)

After generating this authorize_url, you (or users of your application) will need to visit it and accept the OAuth 2.0 prompt. If this is within a web application, you can simply redirect, otherwise you’ll need to visit the link in a browser.

After authorizing, exchange the code for a token:

import atom.http_core

redirect_url = 'http://www.example.com/oauth2callback?code=SOME-RETURNED-VALUE'
url = atom.http_core.ParseUri(redirect_url)
auth_token.get_access_token(url.query)

In the case you visited a browser, you’ll need to copy the URL you were redirected to into the variable redirect_url.

In the case you are in a web application, you will be able to specify the handler for the path /oauth2callback (for example) and simply can retrieve the query parameter code to exchange the code for a token. For example, if using WebOb:

redirect_url = atom.http_core.Uri.parse_uri(self.request.uri)

Finally authorize your client with this token:

import gdata.contacts.service

client = gdata.contacts.service.ContactsService(source='appname')
auth_token.authorize(client)

Update (12+ months after original answer):

Alternately you can use the google-api-python-client support as I describe in a blog post.