MotorClientSession – Sequence of operations

class motor.motor_tornado.MotorClientSession(delegate, motor_client)

A session for ordering sequential operations.

Do not create an instance of MotorClientSession directly; use MotorClient.start_session():

collection = client.db.collection

async with await client.start_session() as s:
    async with s.start_transaction():
        await collection.delete_one({'x': 1}, session=s)
        await collection.insert_one({'x': 2}, session=s)

New in version 2.0.

coroutine abort_transaction()

Abort a multi-statement transaction.

coroutine commit_transaction()

Commit a multi-statement transaction.

coroutine end_session()

Finish this session. If a transaction has started, abort it.

It is an error to use the session after the session has ended.

start_transaction(read_concern=None, write_concern=None, read_preference=None)

Start a multi-statement transaction.

Takes the same arguments as TransactionOptions.

Best used in a context manager block:

# Use "await" for start_session, but not for start_transaction.
async with await client.start_session() as s:
    async with s.start_transaction():
        await collection.delete_one({'x': 1}, session=s)
        await collection.insert_one({'x': 2}, session=s)

advance_cluster_time

Update the cluster time for this session.

Parameters:

• cluster_time: The cluster_time from another ClientSession instance.

advance_operation_time

Update the operation time for this session.

Parameters:

• operation_time: The operation_time from another ClientSession instance.

client

The MotorClient this session was created from.

cluster_time

The cluster time returned by the last operation executed in this session.

has_ended

True if this session is finished.

operation_time

The operation time returned by the last operation executed in this session.

options

The SessionOptions this session was created with.

session_id

A BSON document, the opaque server session identifier.