Metadata-Version: 1.1
Name: plib
Version: 0.8.3
Summary: A namespace package for a number of useful sub-packages and modules.
Home-page: http://pypi.python.org/pypi/plib
Author: Peter A. Donis
Author-email: peterdonis@alum.mit.edu
License: UNKNOWN
Description: The PLIB package contains a number of useful sub-packages and
        modules, all within the ``plib`` package namespace in order to
        minimize clutter in the top-level namespace of your Python
        installation. Each sub-directory of the ``plib`` directory
        contains a sub-package, except for the ``test`` directory, which
        contains the PLIB test suite. The source distribution also
        contains an ``examples`` directory, which has example programs
        using PLIB, and a ``scripts`` directory, which has a few
        post-install scripts. Finally, the ``setup.py`` script for
        PLIB uses the ``setuputils`` helper module, which helps to
        automate away much of the boilerplate in Python setup scripts.
        This module is available as a separate release at
        http://pypi.python.org/pypi/setuputils.
        
        This version of PLIB is intended to run on the latest Python
        2 versions. It has been tested on 2.7, but most of it should
        run on 2.6 as well; the main known exception is the ``options``
        module in ``plib.stdlib``, which uses the ``argparse`` standard
        library module that was added in 2.7. If you need to run PLIB
        on earlier Python versions, the "legacy" version of PLIB is
        available at http://pypi.python.org/pypi/plib2 as the ``plib2``
        package. However, the PLIB API in this and future versions is
        considerably changed from the "legacy" API, so programs written
        using ``plib2`` will have to be ported to the new API to use
        this or future PLIB versions.
        
        The PLIB Sub-Packages
        =====================
        
        The individual sub-packages and modules contain docstrings
        with more information about their usage; here they are
        briefly listed and described.
        
        (Note: eventually it is planned to have each major sub-package
        available as a separate release, so you can install only what
        you need. PLIB.STDLIB is required by all the others, so it will
        always be there; but, for example, if you're using PLIB on a
        server you don't need PLIB.GUI. The Python packaging mechanism
        is still in flux so this scheme is on hold until the dust
        settles; it may only be feasible in Python 3.)
        
        PLIB.GUI
        --------
        
        This sub-package contains a simple GUI application framework
        with two main features:
        
        - It lets the same high-level code work with a number of
          different underlying GUI toolkits. Currently supported:
          Qt (versions 3 and 4), KDE (versions 3 and 4), wxWidgets,
          and GTK. (The original reason for writing this sub-package
          was that wxWidgets doesn't use Qt and I like the Qt/KDE
          widgets better, but I wanted code that would run
          cross-platform.)
        
        - It allows you to express the layout of your GUI in terms
          of Python lists and dicts, enabling a much more declarative
          and easy to read (and maintain) coding style.
        
        Other than selecting the toolkit (which may not be necessary:
        the main module of the sub-package can 'auto-detect' which
        toolkit to use--the ``plib-setup-gui`` post-install script
        does most of the work to enable this--so you only need to
        override if you don't like the default), you should not have
        to worry about any toolkit internal details; the goal of this
        sub-package is to make them all look the same to your code.
        
        Note that the GTK toolkit support in this sub-package is
        "experimental" and may be removed if it proves to be more
        trouble than it's worth. It's currently included because
        wxWidgets' behavior when using GTK as its underlying GUI
        framework has some quirks that I haven't been able to work
        around yet. However, the GTK implementation of a number of
        widgets (particularly tables and list/tree views) is much
        less capable than the wxWidgets one, so the Python code for
        GTK ends up relying much more on ugly hacks.
        
        PLIB.IO
        -------
        
        This sub-package contains classes that encapsulate various forms
        of client/server I/O channels. It is organized into sub-packages
        itself to make the namespace easier to use. First, the ``base``
        sub-package contains base classes that implement common basic
        functionality that is built on by the rest of PLIB.IO.
        
        Most of the remaining sub-packages fall into three main categories,
        and each sub-package in a given category contains the same basic
        class names, so they're easier to remember. The categories are:
        
        - **Device Types**: ``socket`` and ``serial``. Each device type has
          a ``BaseClient`` and ``BaseServer`` class; the ``socket`` type
          also has a ``BaseRequest`` class. These will usually not need to
          be used directly; they are used by the I/O mode classes, and are
          factored out so that each I/O mode sees the same API for a given
          device type.
        
        - **I/O modes**: ``async`` and ``blocking`` (the latter does not just
          mean synchronous: it includes a forking TCP socket server). Each
          I/O mode has a client and server class for both device types, and
          a request class for the ``socket`` device type: the class names are
          ``SerialClient``, ``SerialServer``, ``SocketClient``, ``SocketServer``,
          and ``BaseRequestHandler``. The ``async`` type also has "persistent"
          classes, which support full-duplex asynchronous communication; these
          are the ``PersistentSerial``, ``PersistentSocket``, and
          ``PersistentRequestHandler`` classes. Mixin versions of these classes
          (class names with ``Mixin`` at the end) are also provided, for use
          if alternate data handling is desired (see next bullet), but it is
          normally not necessary to use these "by hand"--see "automatic mixins"
          below.
        
        - **Data Handling**: the I/O mode classes given above include basic
          data handling, but it is *very* basic: the only way it can detect
          that a "message" has been fully received is to detect a closed
          channel. For some applications this is enough, but often more
          sophisticated and robust data handling is needed. The ``data``
          sub-package provides three mixin classes for this purpose,
          ``ShutdownReadWrite``, ``TerminatorReadWrite`` and ``ReadWrite``.
          The first of these detects the end of a received message by a
          shutdown of the other end of the data channel, but keeps the channel
          open to allow further writes (all the other classes default to
          closing the channel when the other end closes). The other two
          classes allow the detection of multiple "messages" in the data
          stream, either by detecting a "terminator" string or by having
          each message include its length at the beginning. These classes
          also format outgoing messages the same way.
        
        There is also a ``mixins`` sub-package containing classes that
        are used as mixins by the other sub-packages, and a ``classes``
        sub-package containing higher-level classes that use the API.
        Finally, there is a ``chatgen`` module which contains a simple
        class, ``chat_replies``, that yields replies from a remote server
        as a generator, and a ``utils`` module that implements the automatic
        mixin functionality described below.
        
        *Automatic Mixins*: To derive your own client or server classes with
        alternate data handling "by hand", you would need to use the "mixin"
        versions of the appropriate I/O mode classes, and splice the data
        handling class into the middle of the base class list; for example::
        
            from plib.io.async import SerialClientMixin, SerialBase
            from plib.io.data import TerminatorReadWrite
            
            class AsyncSerialClientWithTerminator(SerialClientMixin,
                TerminatorReadWrite, SerialBase): pass
        
        This is a bit clumsy, but necessary since the read/write handling has
        to be *before* the client/server class in the MRO, but *after* the
        base device type, for the cooperative ``super`` calls that underlie
        the functionality to work properly. However, since the pattern is the
        same in each case, it can be automated, and this has been done in the
        ``async`` and ``blocking`` sub-package namespaces, so that instead of
        doing the above class construction "by hand", you can just append a
        suffix to your desired class name, thus::
        
            from plib.io.async import SerialClientWithTerminator
        
        The ``WithTerminator`` suffix (or, alternately, ``WithShutdown``
        or ``WithReadWrite``) will cause the equivalent of the above class
        definition to occur on the fly, so that the resulting class appears
        in the ``plib.io.async`` namespace (of course the
        ``plib.io.blocking`` namespace has the same capability).
        Once this has happened the first time, however, the class definition
        is stored in the appropriate namespace, so additional imports of the
        same class name (in different modules of your application) will not
        re-do the "on the fly" construction; they will just retrieve the
        same class object that was previously constructed.
        
        The above machinery is also made available for use with your own custom
        read/write handling classes; the ``async`` and ``blocking`` sub-packages
        each export a ``get_readwrite_class`` function that does the same
        on-the-fly class definition as above, but with your custom read/write
        class instead of one of the built-in ones. All you have to do is pass
        the function the name of your desired I/O class and your custom
        read/write class object::
        
            from plib.io import async
            
            class CustomReadWrite(object):
                # class definition
            
            MyAsyncSerialClient = async.get_readwrite_class('SerialClient',
                CustomReadWrite)
        
        *API Notes*: One of the goals of this sub-package is to provide a
        common, consistent API for all the different types of I/O, so that
        switching one specific implementation of a certain functionality
        for another can be done transparently to the rest of your application's
        code. Thus, all of the usable classes follow the same basic pattern of
        mixing in the various pieces of functionality: from left to right
        in a class's MRO, one finds the type of endpoint (a client or
        server mixin class, which may be specialized to the type of I/O),
        the type of data formatting, if any (a mixin class from the
        ``ReadWrite`` module), and the type of I/O, including device type
        (socket, serial port, etc.), mode (non-blocking/asynchronous vs.
        blocking), and basic data handling. Also, each endpoint type has
        a common API independent of the specific type of I/O and mode; a
        client can always use the ``client_communicate`` method to send
        data to the server and receive a response; a server can always use
        the ``serve_forever`` method to start itself; and all I/O objects
        override the same methods to implement application-specific
        functionality: ``process_data``, to deal with data as it comes in,
        and ``query_done``, to determine when the I/O channel should be
        closed. (To see examples of all this in action, look at the test
        suite in ``test_io.py`` and the library module for it,
        ``io_testlib.py``; the library module can use the same
        mixin classes to implement test functionality for *all* of the
        different mixes of I/O classes in the test suite.)
        
        PLIB.STDLIB
        -----------
        
        This is a namespace for various functions and classes that
        extend or emulate the Python standard library. Some,
        like the ``cached_property`` decorator, are implementations of
        patterns that have been known for some time, but which don't
        have a "canonical" version in the stdlib yet; rather than
        have PLIB depend on some other third-party package, I've
        simply provided my own implementations here. Others, like
        the ``abstractcontainer`` class and its subclasses, are
        re-implementations of standard Python data structures,
        written to enable PLIB to make as many things as possible
        look like those data structures without having to subclass
        the built-ins (which has some downsides for the use cases
        I've had thus far--see the docstrings for more information).
        
        The following modules or sub-packages are available in the
        ``plib.stdlib`` namespace:
        
        - The ``builtins`` module contains some funtions that should be
          Python builtins, but aren't. :) Importing the module adds those
          functions to the built-in namespace; this is mostly useful for
          interactive shells. The functions can also be imported directly
          from ``plib.stdlib.builtins``, to make it easier to understand
          where the functions are coming from in module code.
        
        - The ``classes`` sub-package provides some miscellaneous useful
          classes.
        
        - The ``classtools`` module provides some utilities for working
          with classes and class attributes.
        
        - The ``cmdline`` module provides utilities useful for command
          line programs and interactive shells.
        
        - The ``coll`` sub-package provides various collection classes,
          including abstract collections built on the ``collections``
          ABCs from the standard library.
        
        - The ``comm`` sub-package provides utilities for managing and
          communicating with child threads and processes.
        
        - The ``decotools`` module provides functions and factories for
          working with decorators.
        
        - The ``extensions`` sub-package provides a namespace for functions
          (and possibly, in the future, other objects) exported from an
          extension module written using the Python/C API. The general
          philosophy of PLIB is to do everything possible in pure
          Python, so the only functions that appear in this sub-package
          are those which by their very nature cannot be done in pure
          Python.
        
        - The ``fdtools`` module provides utilities for working with file
          descriptors.
        
        - The ``imp`` module provides the ``import_from_module`` function,
          which should be in the standard library ``importlib`` module
          but isn't. :)
        
        - The ``ini`` sub-package implements an abstract 'INI file' API that
          uses ``ConfigParser`` on POSIX systems, and the Windows registry
          on Windows systems. This API allows the configuration file
          structure to be declared using Python lists and dicts.
        
        - The ``iters`` module provides various functions dealing with
          or returning iterables.
        
        - The ``localize`` module provides useful functions for getting
          locale-specific information.
        
        - The ``mail`` module provides a useful shortcut function for
          sending email from programs.
        
        - The ``mathlib`` module provides some additional math functions
          to supplement those in the standard library.
        
        - The ``net`` module provides utilities for getting information
          about networks.
        
        - The ``options`` module provides an easier-to-use overlay for
          the ``argparse`` module which allows you to express your option
          configuration in the form of Python lists, tuples, and dicts.
        
        - The ``ostools`` module provides utilities for working with the
          operating system.
        
        - The ``proc`` module provides a shortcut function for getting
          the output of a subprocess.
        
        - The ``sigtools`` module provides a low-level implementation of
          the self-pipe trick for signal handling.
        
        - The ``strings`` module provides functions and constants for
          working with strings.
        
        - The ``systools`` module exposes some useful variables giving
          information about the Python runtime system and PLIB itself.
        
        - The ``timer`` module provides functions for timing code, with
          an alternate API to the standard library's ``timeit`` module
          that is easier to use when timing functions that you already
          have as objects, instead of source code strings.
        
        - The ``tztools`` module provides some useful ``tzinfo`` subclasses
          based on those in the Python docs for the ``datetime`` module,
          and a function to return the local system timezone name.
        
        - The ``util`` sub-package provides the ``ModuleProxy`` class, which
          is used by a number of PLIB sub-packages. See the docstrings
          for the class and the sub-packages using it for more information.
        
        - The ``version`` module provides a version class that can take a
          standard version tuple as its constructor argument.
        
        PLIB.XML
        --------
        
        This sub-package requires the ``lxml`` extension, which uses
        the very fast ``libxml2`` library but provides a Pythonic API
        similar to ``ElementTree``. The reason for using ``lxml`` instead
        of ``ElementTree`` itself is that ``lxml`` has two key additional
        features:
        
        - Custom element classes: the ``classes`` module in this
          sub-package builds on this feature by using metaclasses
          to automate DTD generation and validation, but the
          feature is also great for many XML applications.
        
        - Full and *fast* XPATH support: this was key in the XML
          application that first prompted me to write this sub-package.
          Yes, I know there are plenty of other Python XML packages
          that do XPATH; the point is to have it *plus* the standard
          ``ElementTree`` API *plus* the speed of ``libxml2``.
        
        Installation
        ============
        
        To install PLIB, you can simply run::
        
            $ python setup.py install
        
        at a shell prompt from the directory into which you
        unzipped the source tarball (the same directory that this
        README file is in). This will install PLIB and then
        run each of the post-install scripts in the scripts
        directory.
        
        Example Programs
        ================
        
        PLIB comes with example programs that illustrate key features
        of the package. After installation, these can be found in the
        ``$PREFIX/share/plib/examples`` directory. If you have a
        POSIX system (Linux or Mac OSX), the ``plib-setup-examples``
        post-install script will install symlinks to the example
        programs in the ``$PREFIX/bin`` directory.
        
        
Platform: UNKNOWN
Classifier: Development Status :: 3 - Alpha
Classifier: Environment :: Console
Classifier: Environment :: MacOS X
Classifier: Environment :: Win32 (MS Windows)
Classifier: Environment :: X11 Applications :: GTK
Classifier: Environment :: X11 Applications :: KDE
Classifier: Environment :: X11 Applications :: Qt
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: GNU General Public License v2 (GPLv2)
Classifier: Operating System :: MacOS :: MacOS X
Classifier: Operating System :: Microsoft :: Windows
Classifier: Operating System :: POSIX
Classifier: Operating System :: POSIX :: Linux
Classifier: Programming Language :: Python
Classifier: Topic :: Software Development :: Libraries :: Python Modules
Provides: plib (0.8.3)
