def process_request(data):
if data.startswith('wyd'):
return transactions._transaction_manager.transaction_statuses
elif data.startswith('BEGIN TRANSACTION'):
return transactions.begin_transaction()
elif data.startswith('COMMIT'):
txn_id = int(data.split()[1])
return transactions.commit(txn_id)
elif data.startswith('ROLLBACK'):
txn_id = int(data.split()[1])
return transactions.rollback(txn_id)
elif data.startswith('TRANSACTION'):
words = data.split()
txn_id = int(words[1])
if not txn_id in transactions._transaction_manager.transactions:
return "txn %s does not exist yet" % txn_id
operation = words[2]
row_id = int(words[3])
if operation == 'READ':
return access.read(txn_id, row_id)
elif operation == 'WRITE':
value = words[4]
return access.write(txn_id, row_id, value)
def test_prefers_transaction_specific_value(self):
storage.write_row(1, 'main', 1, {'value': 'test'}, 1)
storage.write_row(2, 'main', 1, {'value': 'updated'}, 1)
response = access.read(2, 1)
self.assertEqual(response, {1: {'value': 'updated'}})
def test_returns_stored_value(self):
storage.write_row(1, 'main', 1, {'value': 'test'}, 1)
storage.write_row(2, 'main', 1, {'value': 'updated'}, 1)
response = access.read(1, 1)
self.assertEqual(response, {1: {'value': 'test'}})
def test_returns_none_if_data_does_not_exist(self):
response = access.read(1, 1)
self.assertEqual(response, {1: None})
def test_fails_gracefully_if_read_lock_collision(self):
with patch('pokedb.locks.get_locks_for_read',
side_effect=LockException):
response = access.read(1, 1)
self.assertEqual(response, "Lock collision for read")
def test_calls_lock_module_to_take_out_locks(self):
with patch('pokedb.locks.get_locks_for_read') as mock_lock:
access.read(1, 1)
mock_lock.assert_called_once_with(1, 'main', [1])