Merge pull request #15 from orestica/get_access_token

Modify the OAuth2Credentials.get_access_token() method.

oauth2client/client.py

@@ -31,6 +31,7 @@ import time
 import urllib
 import urlparse
 
+from collections import namedtuple
 from oauth2client import GOOGLE_AUTH_URI
 from oauth2client import GOOGLE_REVOKE_URI
 from oauth2client import GOOGLE_TOKEN_URI
@@ -75,6 +76,9 @@ SERVICE_ACCOUNT = 'service_account'
 # The environment variable pointing the file with local Default Credentials.
 GOOGLE_CREDENTIALS_DEFAULT = 'GOOGLE_CREDENTIALS_DEFAULT'
 
+# The access token along with the seconds in which it expires.
+AccessTokenInfo = namedtuple('AccessTokenInfo', ['access_token', 'expires_in'])
+
 class Error(Exception):
   """Base error for this module."""
 
@@ -600,18 +604,17 @@ class OAuth2Credentials(Credentials):
     return False
 
   def get_access_token(self, http=None):
-    """Return the access token.
+    """Return the access token and its expiration information.
 
     If the token does not exist, get one.
     If the token expired, refresh it.
     """
-    if self.access_token and not self.access_token_expired:
+    if not self.access_token or self.access_token_expired:
-      return self.access_token
-    else:
       if not http:
         http = httplib2.Http()
       self.refresh(http)
-      return self.access_token
+    return AccessTokenInfo(access_token=self.access_token,
+                           expires_in=self._expires_in())
 
   def set_store(self, store):
     """Set the Storage for the credential.
@@ -625,6 +628,25 @@ class OAuth2Credentials(Credentials):
     """
     self.store = store
 
+  def _expires_in(self):
+    """Return the number of seconds until this token expires.
+    
+    If token_expiry is in the past, this method will return 0, meaning the
+    token has already expired.
+    If token_expiry is None, this method will return None. Note that returning
+    0 in such a case would not be fair: the token may still be valid;
+    we just don't know anything about it. 
+    """
+    if self.token_expiry:
+      now = datetime.datetime.utcnow()
+      if self.token_expiry > now:
+        time_delta = self.token_expiry - now
+        # TODO(orestica): return time_delta.total_seconds()
+        # once dropping support for Python 2.6
+        return time_delta.days * 86400 + time_delta.seconds
+      else:
+        return 0
+
   def _updateFromCredential(self, other):
     """Update this Credential from another instance."""
     self.__dict__.update(other.__getstate__())

tests/test_appengine.py

@@ -245,7 +245,8 @@ class TestAppAssertionCredentials(unittest.TestCase):
 
     credentials = AppAssertionCredentials(['dummy_scope'])
     token = credentials.get_access_token()
-    self.assertEqual('a_token_123', token)
+    self.assertEqual('a_token_123', token.access_token)
+    self.assertEqual(None, token.expires_in)
 
 
 class TestFlowModel(db.Model):

tests/test_gce.py

@@ -125,8 +125,9 @@ class AssertionCredentialsTests(unittest.TestCase):
     http = httplib2.Http()
     http.request = httplib2_request
 
-    self.assertEquals('this-is-a-token',
+    token = credentials.get_access_token(http=http)
-                      credentials.get_access_token(http=http))
+    self.assertEqual('this-is-a-token', token.access_token)
+    self.assertEqual(None, token.expires_in)
 
     m.UnsetStubs()
     m.VerifyAll()

tests/test_oauth2client.py

@@ -583,28 +583,32 @@ class BasicCredentialsTests(unittest.TestCase):
     self.assertEqual('foobar', instance.token_response)
 
   def test_get_access_token(self):
-    token_response_first = {'access_token': 'first_token', 'expires_in': 1}
+    S = 2  # number of seconds in which the token expires
-    token_response_second = {'access_token': 'second_token', 'expires_in': 1}
+    token_response_first = {'access_token': 'first_token', 'expires_in': S}
+    token_response_second = {'access_token': 'second_token', 'expires_in': S}
     http = HttpMockSequence([
         ({'status': '200'}, simplejson.dumps(token_response_first)),
         ({'status': '200'}, simplejson.dumps(token_response_second)),
     ])
 
-    self.assertEqual('first_token',
+    token = self.credentials.get_access_token(http=http)
-                     self.credentials.get_access_token(http=http))
+    self.assertEqual('first_token', token.access_token)
+    self.assertEqual(S - 1, token.expires_in)
     self.assertFalse(self.credentials.access_token_expired)
     self.assertEqual(token_response_first, self.credentials.token_response)
 
-    self.assertEqual('first_token',
+    token = self.credentials.get_access_token(http=http)
-                     self.credentials.get_access_token(http=http))
+    self.assertEqual('first_token', token.access_token)
+    self.assertEqual(S - 1, token.expires_in)
     self.assertFalse(self.credentials.access_token_expired)
     self.assertEqual(token_response_first, self.credentials.token_response)
 
-    time.sleep(1)
+    time.sleep(S)
     self.assertTrue(self.credentials.access_token_expired)
 
-    self.assertEqual('second_token',
+    token = self.credentials.get_access_token(http=http)
-                     self.credentials.get_access_token(http=http))
+    self.assertEqual('second_token', token.access_token)
+    self.assertEqual(S - 1, token.expires_in)
     self.assertFalse(self.credentials.access_token_expired)
     self.assertEqual(token_response_second, self.credentials.token_response)
 

tests/test_service_account.py

@@ -94,27 +94,31 @@ class ServiceAccountCredentialsTests(unittest.TestCase):
     self.assertEqual('dummy_scope', new_credentials._scopes)
 
   def test_access_token(self):
-    token_response_first = {'access_token': 'first_token', 'expires_in': 1}
+    S = 2  # number of seconds in which the token expires
-    token_response_second = {'access_token': 'second_token', 'expires_in': 1}
+    token_response_first = {'access_token': 'first_token', 'expires_in': S}
+    token_response_second = {'access_token': 'second_token', 'expires_in': S}
     http = HttpMockSequence([
         ({'status': '200'}, simplejson.dumps(token_response_first)),
         ({'status': '200'}, simplejson.dumps(token_response_second)),
     ])
 
-    self.assertEqual('first_token',
+    token = self.credentials.get_access_token(http=http)
-                     self.credentials.get_access_token(http=http))
+    self.assertEqual('first_token', token.access_token)
+    self.assertEqual(S - 1, token.expires_in)  
     self.assertFalse(self.credentials.access_token_expired)
     self.assertEqual(token_response_first, self.credentials.token_response)
 
-    self.assertEqual('first_token',
+    token = self.credentials.get_access_token(http=http)
-                     self.credentials.get_access_token(http=http))
+    self.assertEqual('first_token', token.access_token)
+    self.assertEqual(S - 1, token.expires_in)
     self.assertFalse(self.credentials.access_token_expired)
     self.assertEqual(token_response_first, self.credentials.token_response)
 
-    time.sleep(1)
+    time.sleep(S)
     self.assertTrue(self.credentials.access_token_expired)
 
-    self.assertEqual('second_token',
+    token = self.credentials.get_access_token(http=http)
-                     self.credentials.get_access_token(http=http))
+    self.assertEqual('second_token', token.access_token)
+    self.assertEqual(S - 1, token.expires_in)
     self.assertFalse(self.credentials.access_token_expired)
     self.assertEqual(token_response_second, self.credentials.token_response)