Alchemytools 0.2

Alchemytools is a set of helpers to be used in any SQLAlchemy project

This project brings a set of useful tools to be used in any SQLAchemly project.

The idea is to save common problems, for example: Opening/Closing sessions, commiting the sesssin only at the end of the transaction, etc.

Available Tools

Here are all tools available in alchemytools.

Context Managers

managed

This is the basic context manager and it will commit and close your session automatically, at the end of the with block.

with managed(MySessionClass) as session:
    # Do what you need with your session
# Here the session is already closed and commited

If you raise any exception inside the with block, the session will be rolled back and the exception re-raised.

Additional options

• auto_flush: Sets the autoflush option on the SQLAlchemy session, defaults fo False

commit_on_success

This contextmanager should be used in an inner with block, where you already have an open session but need to commit more than one time. The code will be something on these lines.

with managed(MySession) as session:
    for a in iterable:
        with commit_on_success(session):
            process(a)
            session.add(a)

If you raise an exception inside the second with block, all previous iterations will already be commited and just the current one will be rolledback.