Adding gmail oauth2 authentication

python-social-auth is an optional dependency

django_mailbox/google_utils.py

@@ -0,0 +1,126 @@
+from social.apps.django_app.default.models import UserSocialAuth
+import requests
+from django.conf import settings
+
+
+class AccessTokenNotFound(Exception):
+    pass
+
+
+class RefreshTokenNotFound(Exception):
+    pass
+
+
+def get_google_consumer_key():
+    return settings.SOCIAL_AUTH_GOOGLE_OAUTH2_KEY
+
+
+def get_google_consumer_secret():
+    return settings.SOCIAL_AUTH_GOOGLE_OAUTH2_SECRET
+
+
+def get_google_access_token(email):
+    # TODO: This should be cacheable
+    try:
+        me = UserSocialAuth.objects.get(uid=email, provider="google-oauth2")
+        return me.extra_data['access_token']
+    except (UserSocialAuth.DoesNotExist, KeyError):
+        raise AccessTokenNotFound
+
+
+def update_google_extra_data(email, extra_data):
+    try:
+        me = UserSocialAuth.objects.get(uid=email, provider="google-oauth2")
+        me.extra_data = extra_data
+        me.save()
+    except (UserSocialAuth.DoesNotExist, KeyError):
+        raise AccessTokenNotFound
+
+
+def get_google_refresh_token(email):
+    try:
+        me = UserSocialAuth.objects.get(uid=email, provider="google-oauth2")
+        return me.extra_data['refresh_token']
+    except (UserSocialAuth.DoesNotExist, KeyError):
+        raise RefreshTokenNotFound
+
+
+def google_api_get(email, url):
+    headers = dict(
+        Authorization="Bearer %s" % get_google_access_token(email),
+    )
+    r = requests.get(url, headers=headers)
+    print "I got a %s" % r.status_code
+    if r.status_code == 401:
+        # Go use the refresh token
+        refresh_authorization(email)
+        r = requests.get(url, headers=headers)
+        print "I got a %s" % r.status_code
+    if r.status_code == 200:
+        try:
+            return r.json()
+        except ValueError:
+            print "returning text"
+            return r.text
+
+
+def google_api_post(email, url, post_data, authorized=True):
+    # TODO: Make this a lot less ugly. especially the 401 handling
+    headers = dict()
+    if authorized is True:
+        headers.update(dict(
+            Authorization="Bearer %s" % get_google_access_token(email),
+        ))
+    r = requests.post(url, headers=headers, data=post_data)
+    if r.status_code == 401:
+        refresh_authorization(email)
+        r = requests.post(url, headers=headers, data=post_data)
+    if r.status_code == 200:
+        try:
+            return r.json()
+        except ValueError:
+            print "returning text"
+            return r.text
+
+
+def refresh_authorization(email):
+    refresh_token = get_google_refresh_token(email)
+    post_data = dict(
+        refresh_token=refresh_token,
+        client_id=get_google_consumer_key(),
+        client_secret=get_google_consumer_secret(),
+        grant_type='refresh_token',
+    )
+    results = google_api_post(
+        email,
+        "https://accounts.google.com/o/oauth2/token?access_type=offline",
+        post_data,
+        authorized=False)
+    results.update({'refresh_token': refresh_token})
+    update_google_extra_data(email, results)
+
+
+def fetch_user_info(email):
+    result = google_api_get(
+        email,
+        "https://www.googleapis.com/oauth2/v1/userinfo?alt=json"
+    )
+    return result
+
+
+def fetch_google_contacts(email, limit=10000):
+    result = google_api_get(
+        email,
+        "https://www.google.com/m8/feeds/contacts/default/full?v=3.0&alt=json&max-results=%s" % limit
+    )
+    entries = result['feed']['entry']
+    valid_entries = [x for x in entries if u'gd$email' in x.keys() and u'gd$name' in x.keys()]
+    contacts = []
+    for each in valid_entries:
+        try:
+            name = each[u'gd$name'][u'gd$fullName'][u'$t']
+        except KeyError:
+            name = None
+        for each_email in each[u'gd$email']:
+            contacts.append(dict(name=name, email=each_email[u'address']))
+    return contacts

django_mailbox/transports/__init__.py

@@ -5,3 +5,4 @@ from django_mailbox.transports.mbox import MboxTransport
 from django_mailbox.transports.babyl import BabylTransport
 from django_mailbox.transports.mh import MHTransport
 from django_mailbox.transports.mmdf import MMDFTransport
+from django_mailbox.transports.gmail import GmailImapTransport

django_mailbox/transports/gmail.py

@@ -0,0 +1,49 @@
+from django_mailbox.transports.imap import ImapTransport
+
+class GmailImapTransport(ImapTransport):
+
+    def connect(self, username, password):
+        # Try to use oauth2 first.  It's much safer
+        try:
+            self._connect_oauth(username)
+        except (TypeError, ValueError), e:
+            print " Couldn't do oauth2", e
+            self.server = self.transport(self.hostname, self.port)
+            typ, msg = self.server.login(username, password)
+            self.server.select()
+
+    def _connect_oauth(self, username):
+        # username should be an email address that has already been authorized
+        # for gmail access
+        try:
+            from django_mailbox.google_utils import (
+                get_google_access_token,
+                fetch_user_info,
+                AccessTokenNotFound,
+            )
+        except ImportError:
+            raise ValueError(
+                "Install python-social-auth to use oauth2 auth for gmail"
+            )
+
+        access_token = None
+        while access_token is None:
+            try:
+                access_token = get_google_access_token(username)
+                google_email_address = fetch_user_info(username)['email']
+            except TypeError:
+                # This means that the google process took too long
+                # Trying again is the right thing to do
+                pass
+            except AccessTokenNotFound:
+                raise ValueError(
+                    "No Token available in python-social-auth for %s" % username
+                )
+
+        auth_string = 'user=%s\1auth=Bearer %s\1\1' % (
+            google_email_address,
+            access_token
+        )
+        self.server = self.transport(self.hostname, self.port)
+        self.server.authenticate('XOAUTH2', lambda x: auth_string)
+        self.server.select()