Google contacts import using oauth2.0

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.

Answer 2

Final solution was relatively easy.

Step 1 Obtain oauth2.0 token. It's pretty documented in official docs: http://code.google.com/p/google-api-python-client/wiki/OAuth2

Step 2 Now we have token, but can not discover contacts API. But you can find, that in oauth2.0 playground you can import contacts. https://code.google.com/oauthplayground/

You can find, that you have access token in credentials, obtained in Step 1. To access contacts api you must add to headers following param 'Authorization':'OAuth %s' % access_token

Step 3 Now you must pass to google library token, that will be compatible with oauth1.0 token. It can be done by following code:

from atom.http import ProxiedHttpClient #Google contacts use this client
class OAuth2Token(object):
    def __init__(self, access_token):
        self.access_token=access_token

    def perform_request(self, *args, **kwargs):
        url = 'http://www.google.com/m8/feeds/contacts/default/full'
        http = ProxiedHttpClient()
        return http.request(
            'GET',
            url,
            headers={
                'Authorization':'OAuth %s' % self.access_token
            }
        )
google = gdata.contacts.service.ContactsService(source='appname')
google.current_token = OAuth2Token(oauth2creds.access_token)
feed = google.GetContactsFeed()