def main():
collection = prepare()
collection.insert_many([{'_id': i} for i in range(7)])
search_condictions = {
'collection': collection,
'filter': {},
'sort': [('_id', 1)],
'limit': 5,
}
# gets the first page
cursor1 = get_keyset_cursor(**search_condictions)
print('page1:', list(cursor1)) # [{'_id': 0}, {'_id': 1}, {'_id': 2}, {'_id': 3}, {'_id': 4}]
# gets the second page
cursor2 = get_keyset_cursor(**search_condictions, position=cursor1.paging.next_position)
print('page2:', list(cursor2)) # [{'_id': 5}, {'_id': 6}]
collection.insert({'_id': -1})
# the first page again, backwards from the previous page
cursor1 = get_keyset_cursor(**search_condictions, position=cursor2.paging.previous_position)
print('page1:', list(cursor1)) # [{'_id': 0}, {'_id': 1}, {'_id': 2}, {'_id': 3}, {'_id': 4}]
# what if new items were added at the start?
if cursor1.paging.has_previous:
cursor0 = get_keyset_cursor(**search_condictions, position=cursor1.paging.previous_position)
print('page0:', list(cursor0)) # [{'_id': -1}]
def test_single_sort_case(self):
search_condictions = {
'collection': self.collect,
'limit': 3,
'sort': [('_id', 1)],
}
cursor1 = get_keyset_cursor(**search_condictions)
self.assert_cursor(cursor1, self.objs[:3], has_next=True)
cursor2 = get_keyset_cursor(**search_condictions,
position=cursor1.paging.next_position)
self.assert_cursor(cursor2, self.objs[3:6], has_next=True)
cursor3 = get_keyset_cursor(**search_condictions,
position=cursor2.paging.next_position)
self.assert_cursor(cursor3, self.objs[6:], has_next=False)
cursor2 = get_keyset_cursor(**search_condictions,
position=cursor3.paging.previous_position)
self.assert_cursor(cursor2, self.objs[3:6], has_previous=True)
cursor1 = get_keyset_cursor(**search_condictions,
position=cursor2.paging.previous_position)
self.assert_cursor(cursor1, self.objs[:3], has_previous=False)
def test_mutil_sort_cast(self):
search_condictions = {
'collection': self.collect,
'limit': 3,
'sort': [('m', 1), ('n', 1), ('_id', 1)],
# TODO test some edge index cases
}
cursor1 = get_keyset_cursor(**search_condictions)
self.assert_cursor(cursor1, self.objs[:3], has_next=True)
cursor2 = get_keyset_cursor(**search_condictions,
position=cursor1.paging.next_position)
self.assert_cursor(cursor2, self.objs[3:6], has_next=True)
cursor3 = get_keyset_cursor(**search_condictions,
position=cursor2.paging.next_position)
self.assert_cursor(cursor3, self.objs[6:], has_next=False)
cursor2 = get_keyset_cursor(**search_condictions,
position=cursor3.paging.previous_position)
self.assert_cursor(cursor2, self.objs[3:6], has_previous=True)
cursor1 = get_keyset_cursor(**search_condictions,
position=cursor2.paging.previous_position)
self.assert_cursor(cursor1, self.objs[:3], has_previous=False)
def test_mulit_filter(self):
params = dict(filter={'a': {'$gt': 0}, 'b': 0}, limit=2, sort=[['a', 1]], collection=self.collect)
cursor1 = get_keyset_cursor(**params)
self.assertEqual([i['a'] for i in cursor1], [2, 4])
cursor2 = get_keyset_cursor(**params, position=cursor1.paging.next_position)
self.assertEqual([i['a'] for i in cursor2], [6, 8])
def test_single_filter(self):
params = dict(filter={'b': 0}, limit=2, sort=[['a', 1]], collection=self.collect)
cursor1 = get_keyset_cursor(**params)
self.assertEqual([i['a'] for i in cursor1], [0, 2])
cursor2 = get_keyset_cursor(**params, position=cursor1.paging.next_position)
self.assertEqual([i['a'] for i in cursor2], [4, 6])
def test_next(self):
params = dict(collection=self.collect, sort=[['a.b', 1]], limit=20)
cursor1 = get_keyset_cursor(**params)
self.assertEqual([i['a']['b'] for i in cursor1], list(range(0, 20)))
cursor2 = get_keyset_cursor(**params, position=cursor1.paging.next_position)
self.assertEqual([i['a']['b'] for i in cursor2], list(range(20, 40)))
cursor1 = get_keyset_cursor(**params, position=cursor2.paging.previous_position)
self.assertEqual([i['a']['b'] for i in cursor1], list(range(0, 20)))
def test_exclusion_projection(self):
condictions = dict(limit=2, sort=[['a', 1], ['b', 1]], collection=self.collect)
for projection in [{'b': 0}, {'b': 0, '_id': 1}, {'b': 0, '_id': 0}]:
with self.assertRaises(ValueError):
get_keyset_cursor(**condictions, projection=projection)
def test_default_projection(self):
cursor1 = get_keyset_cursor(filter={'b': 0}, limit=2, sort=[['a', 1]], collection=self.collect)
self.assertEqual(cursor1[0].get('b'), 0)
def test_desc_arg(self):
cursor = get_keyset_cursor(sort=[['a', DESCENDING]], limit=3, collection=self.collect)
self.assertEqual([i['a'] for i in cursor], [9, 8, 7])
def test_asc_arg(self):
cursor = get_keyset_cursor(sort=[['a', ASCENDING]], limit=3, collection=self.collect)
self.assertEqual([i['a'] for i in cursor], [0, 1, 2])