Skip to main content

psycopg2 integration with transaction

Project description

psycopg2 integration with transaction

This package provides two-phase commit integration between psycopg2 and the transaction package.

Sample usage:

>>> import psycopg2, psycopg2transaction, transaction

>>> conn = psycopg2.connect(mydsn)
>>> trans = transaction.get()
>>> psycopg2transaction.join(conn, trans)

>>> ... do things with the psycopg2 connection

>>> transaction.commit()

This is just an example. The connection might come from a pool or otherwise already exist, as long as it is in a suitable state to start a distributed transaction.

Similarly, the transaction may come from the thread-local transaction manager, as shown above, or from an application-managed transaction manager.

The critical line in the example above is:

>>> psycopg2transaction.join(conn, trans)

The work done in the connection is committed by calling the transaction’s commit method, typically by calling commit on the transaction’s manager, as shown above.

If you use a thread-local transaction manager (as in the example above), you can omit the transaction argumet to join:

>>> psycopg2transaction.join(conn)

Connection management

Limited connection management is provided:

>>> dsn = 'dbname=test'
>>> conn = psycopg2transaction.join(dsn)
>>> conn = psycopg2transaction.join(dsn)
>>> transaction.commit()

If you pass a connection string rather than a connection to join, a connection will be opened for you and closed when the transaction is committed. If join is called multiple times with the same connection string, then the same connection is used and returned.

Using Postgres notify

You can’t use two-phase commit in postgres transactions in which you’ve used NOTIFY (or LISTEN or UNLISTEN). You can cause NOTIFY to be used after a transaction has committed, but before a managed connection has been closed by passing a notify argument to join with a name of a notification or a sequence of string notification named. The strings may be simple names, or names followed by a comma and string data, as would follow NOTIFY in a notify expression:

>>> conn = psycopg2transaction.join(dsn, notify='myjobs')


0.1.1 (2017-03-18)

  • Package meta data.

0.1.0 (2017-03-18)

Initial release

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

psycopg2transaction-0.1.1.tar.gz (4.7 kB view hashes)

Uploaded source

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Huawei Huawei PSF Sponsor Microsoft Microsoft PSF Sponsor NVIDIA NVIDIA PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page