apipkg 1.3 released

[Ronny Pfannschmidt]

Hello,

i pleased to annouce the release of apipkg 1.3.

Welcome to apipkg!
------------------------

With apipkg you can control the exported namespace of a
python package and greatly reduce the number of imports for your users.
It is a `small pure python module`_ that works on virtually all Python
versions, including CPython2.3 to Python3.1, Jython and PyPy.  It 
co-operates
well with Python's ``help()`` system, custom importers (PEP302) and common
command line completion tools.

Usage is very simple: you can require 'apipkg' as a dependency or you
can copy paste the <200 Lines of code into your project.

As extra it will automatically set package.__version__
to your distribution version.


Tutorial example
-------------------

Here is a simple ``mypkg`` package that specifies one namespace
and exports two objects imported from different modules::

    # mypkg/__init__.py
    import apipkg
    apipkg.initpkg(__name__, {
        'path': {
            'Class1': "_mypkg.somemodule:Class1",
            'clsattr': "_mypkg.othermodule:Class2.attr",
        }
    }

The package is initialized with a dictionary as namespace.

You need to create a ``_mypkg`` package with a ``somemodule.py``
and ``othermodule.py`` containing the respective classes.
The ``_mypkg`` is not special - it's a completely
regular python package.

Namespace dictionaries contain ``name: value`` mappings
where the value may be another namespace dictionary or
a string specifying an import location.  On accessing
an namespace attribute an import will be performed::

    >>> import mypkg
    >>> mypkg.path
    <ApiModule 'mypkg.path'>
    >>> mypkg.path.Class1   # '_mypkg.somemodule' gets imported now
    <class _mypkg.somemodule.Class1 at 0xb7d428fc>
    >>> mypkg.path.clsattr  # '_mypkg.othermodule' gets imported now
    4 # the value of _mypkg.othermodule.Class2.attr

The ``mypkg.path`` namespace and its two entries are
loaded when they are accessed.   This means:

* lazy loading - only what is actually needed is ever loaded

* only the root "mypkg" ever needs to be imported to get
  access to the complete functionality.

* the underlying modules are also accessible, for example::

    from mypkg.sub import Class1


Including apipkg in your package
--------------------------------------

If you don't want to add an ``apipkg`` dependency to your package you
can copy the `apipkg.py`_ file somewhere to your own package,
for example ``_mypkg/apipkg.py`` in the above example.  You
then import the ``initpkg`` function from that new place and
are good to go.

.. _`small pure python module`:
.. _`apipkg.py`: http://bitbucket.org/hpk42/apipkg/src/tip/apipkg.py

Feedback?
-----------------------

If you have questions you are welcome to

* join the #pylib channel on irc.freenode.net
* subscribe to the http://codespeak.net/mailman/listinfo/py-dev list.
* create an issue on http://bitbucket.org/hpk42/apipkg/issues


1.3
----------------------------------------

- fix issue2 - adapt tests on Jython
- handle jython __pkgpath__ missabstraction when running python from jar 
files
- alias modules pointing to unimportable modules will return None for
  all their attributes instead of raising ImportError.  This addresses
  python3.4 where any call to getframeinfo() can choke on sys.modules
  contents if pytest is not installed (because py.test.* imports it).
- introduce apipkg.distribution_version(name) as helper to
  obtain the current version number of a package from install metadata
  its used by default with the package name
- add an eagerloading option and eagerload automatically
  if bpython is used (workaround for their monkeypatching)


-- Ronny