How to use the cloudant.feed.InfiniteFeed function in cloudant

def test_invalid_source_couchdb(self):
        """
        Ensure that a CouchDB client cannot be used with an infinite feed.
        """
        with self.assertRaises(CloudantFeedException) as cm:
            invalid_feed = [x for x in InfiniteFeed(self.client)]
        self.assertEqual(str(cm.exception),
            'Infinite _db_updates feed not supported for CouchDB.')

def test_infinite_feed(self):
        """
        Test that an infinite feed will continue to issue multiple requests
        until stopped.  This check is performed in combination by creating
        documents 3 separate times and checking that the "_start" method on the
        InfiniteFeed object was called 3 times as well.
        """
        self.populate_db_with_documents()
        feed = InfiniteFeed(self.db, timeout=100)

        # Create a proxy for the feed._start method so that we can track how
        # many times it has been called.
        feed._start = MethodCallCount(feed._start)

        changes = list()
        for change in feed:
            self.assertSetEqual(set(change.keys()), set(['seq', 'changes', 'id']))
            changes.append(change)
            if len(changes) in (100, 200):
                sleep(1) # 1 second > .1 second (timeout)
                self.populate_db_with_documents(off_set=len(changes))
            elif len(changes) == 300:
                feed.stop()
        expected = set(['julia{0:03d}'.format(i) for i in range(300)])
        self.assertSetEqual(set([x['id'] for x in changes]), expected)

def test_constructor_no_feed_option(self):
        """
        Test constructing an infinite feed when no feed option is set
        """
        feed = InfiniteFeed(self.db, chunk_size=1, timeout=100)
        self.assertEqual(feed._url, '/'.join([self.db.database_url, '_changes']))
        self.assertIsInstance(feed._r_session, Session)
        self.assertFalse(feed._raw_data)
        self.assertDictEqual(feed._options, {'feed': 'continuous', 'timeout': 100})
        self.assertEqual(feed._chunk_size, 1)

def test_infinite_db_updates_feed(self):
        """
        Test that an _db_updates infinite feed will continue to issue multiple
        requests until stopped.  Since we do not have control over updates
        happening within the account as we do within a database, this test is
        stopped after 15 database creations regardless.  Within that span of
        time we expect that the feed would have been restarted at least once.

        """
        feed = InfiniteFeed(self.client, since='now', timeout=100)

        # Create a proxy for the feed._start method so that we can track how
        # many times it has been called.
        feed._start = MethodCallCount(feed._start)

        new_dbs = list()
        try:
            new_dbs.append(self.client.create_database(self.dbname()))
            for change in feed:
                self.assertTrue(all(x in change for x in ('seq', 'type')))
                new_dbs.append(self.client.create_database(self.dbname()))
                if feed._start.called_count >= 3 and len(new_dbs) >= 3:
                    feed.stop()
                if len(new_dbs) >= 15:
                    # We stop regardless after 15 databases have been created
                    feed.stop()

def test_db_updates_infinite_feed_call(self):
        """
        Test that infinite_db_updates() method call constructs and returns an
        InfiniteFeed object
        """
        try:
            self.client.connect()
            db_updates = self.client.infinite_db_updates()
            self.assertIsInstance(db_updates, InfiniteFeed)
            self.assertEqual(
                db_updates._url, '/'.join([self.client.server_url, '_db_updates']))
            self.assertIsInstance(db_updates._r_session, requests.Session)
            self.assertFalse(db_updates._raw_data)
            self.assertDictEqual(db_updates._options, {'feed': 'continuous'})
        finally:
            self.client.disconnect()

def test_constructor_with_invalid_feed_option(self):
        """
        Test constructing an infinite feed when a feed option is set
        to an invalid value raises an exception.
        """
        feed = InfiniteFeed(self.db, feed='longpoll')
        with self.assertRaises(CloudantArgumentError) as cm:
            invalid_feed = [x for x in feed]
        self.assertEqual(
            str(cm.exception),
            'Invalid infinite feed option: longpoll.  Must be set to continuous.'
        )

def test_constructor_db_updates(self):
        """
        Test constructing an infinite _db_updates feed.
        """
        feed = InfiniteFeed(self.client, chunk_size=1, timeout=100, feed='continuous')
        self.assertEqual(feed._url, '/'.join([self.client.server_url, '_db_updates']))
        self.assertIsInstance(feed._r_session, Session)
        self.assertFalse(feed._raw_data)
        self.assertDictEqual(feed._options, {'feed': 'continuous', 'timeout': 100})
        self.assertEqual(feed._chunk_size, 1)

def test_changes_inifinite_feed_call(self):
        """
        Test that infinite_changes() method call constructs and returns an
        InfiniteFeed object
        """
        changes = self.db.infinite_changes()
        self.assertIsInstance(changes, InfiniteFeed)
        self.assertEqual(changes._url, '/'.join([self.db.database_url, '_changes']))
        self.assertIsInstance(changes._r_session, requests.Session)
        self.assertFalse(changes._raw_data)
        self.assertDictEqual(changes._options, {'feed': 'continuous'})

def test_constructor_with_feed_option(self):
        """
        Test constructing an infinite feed when the continuous feed
        option is set.
        """
        feed = InfiniteFeed(self.db, chunk_size=1, timeout=100, feed='continuous')
        self.assertEqual(feed._url, '/'.join([self.db.database_url, '_changes']))
        self.assertIsInstance(feed._r_session, Session)
        self.assertFalse(feed._raw_data)
        self.assertDictEqual(feed._options, {'feed': 'continuous', 'timeout': 100})
        self.assertEqual(feed._chunk_size, 1)