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Updated README to reflect planned UML 1.5 support.
PEAK Release 0.5 alpha 1

 Copyright (C) 1996-2003 by Phillip J. Eby and Tyler C. Sarna.
 All rights reserved.  This software may be used under the same terms
 Code quality varies between modules, from "beta" to "experimental
 pre-alpha".  :)

 Package Description

    PEAK is the "Python Enterprise Application Kit". If you develop
    "enterprise" applications with Python, or indeed almost any sort of
    application with Python, PEAK may help you do it faster, easier, on a
    larger scale, and with fewer defects than ever before. The key is
    component-based development, on a reliable infrastructure.

    PEAK is an application kit, and applications are made from components.
    PEAK provides you with a component architecture, component infrastructure,
    and various general-purpose components and component frameworks for
    building applications.  As with J2EE, the idea is to let you stop
    reinventing architectural and infrastructure wheels, so you can put more
    time into your actual application.

    But PEAK is different from J2EE: it's a single, free implementation of
    simpler API's based on an easier-to-use language that can nonetheless
    scale with better performance than J2EE.

    PEAK is the successor to TransWarp, an experimental toolkit for software
    automation in Python.  PEAK takes the best of the techniques and ideas
    from TransWarp, and repackages them as an enterprise software toolkit.
    Where TransWarp emphasized techniques like generative programming and
    aspect-oriented programming, PEAK emphasizes enterprise applications,
    and hides the computer science stuff "under the hood", so you can focus
    on building your application.

    PEAK tools can be used with other "Python Enterprise" frameworks such as
    Zope, Twisted, and the Python DBAPI to construct web-based, GUI, or
    command-line applications, interacting with any kind of storage, or with
    no storage at all.  Whatever the application type, PEAK can help you put
    it together.

 Package Features

    As of version 0.5a1, PEAK features include:

    * A component binding framework that makes it easy to parameterize
      components and thus more easily combine and "wire" them together.

    * A comprehensive configuration framework that allows accessing
      "utilities" and "configuration properties" in context.  Properties
      and utilities can be loaded or computed on demand, supplied by rules,
      defined in configuration files or code, in a supplied or custom
      format.  Properties and utilities are contextual and can be safely
      acquired from parent/context components automatically.  System-wide
      (per Python interpreter), application-wide (per running application
      within an interpreter) and per-component configuration settings
      are available.

    * Naming system/framework that's midway between J2EE's JNDI and CORBA's
      cosNaming in features, but much easier to use and extend than either
      of those systems.

    * A storage management and persistence system, including:

        - Atomic, multi-database transactions with two-phase commit.

        - "Data Manager" class framework for persistence management, that
          allows you to separate business logic from storage implementation.
          If you can write a few simple methods like "load" and "save" for
          a given object type and storage approach, you can create your own
          "DM" components.  You can think of a DM as an advanced form of
          Python "shelve", that supports references to other objects,
          transactions, arbitrary back-end storages, and

        - "Stackable" data managers: one DM might serialize a set of objects
          to XML, which could then be stored in a database record by another
          DM, and then the database record might be implemented via a DM
          that writes to disk files!  Each DM only needs to know how to
          manipulate objects offered by the next-level DM, not the details
          of the next DM's implementation, so all the DM's are potentially
          replacable with alternate storage mechanisms.

        - RDBMS and LDAP connection framework based on the Python DBAPI,
          that handles data type conversions (via the configuration
          framework) and seamlessly integrates with the transaction system
          and naming  services framework.  DB Connections can be accessed
          by name or URL, and bound as default collaborators or utilities
          for access by other application components.

    * CASE/modelling tools: PEAK includes APIs to read and write object
      models created in the XML-based XMI format.  Many open-source and
      commercial modelling tools support XMI, inlcuding Argo/Poseidon and
      MagicDraw UML.  PEAK includes pre-built support for UML versions 1.3
      through 1.5, CWM 1.1, and MOF 1.3.1, using XMI versions 1.0 through 1.2.
      Also included, a MOF->Python code generator, which was used to generate
      the UML and CWM support, and which you can use to generate support for
      other modelling languages based on the MOF.

      For the specifications of XMI, MOF, CWM, and UML, visit:

    * A domain modelling framework for creating "business object models"
      with unidirectional and bidirectional associations, generated
      getters/setters and validators for fields, etc., and all necessary
      persistence support for use with the PEAK storage framework.

      The business object framework supplies structural metadata about
      classes built with it, so you can query a class for its fields and
      links, and their names, types, etc.  This can be useful for
      implementing model-driven storage or user interfaces.  And the
      metadata is aligned with the MOF, so generating MOF, UML, or CWM
      from PEAK models (and vice versa) is possible (although
      not yet implemented for anything but MOF->PEAK).

    * AOP and SOP: PEAK allows you to separate concerns as modules, then
      combine the modules via a "module inheritance" technique.  This
      lets you define a generated business object model as a
      "structural" concern, and then combine it with a "behavioral"
      concern.  This is as simple as writing classes that just contain
      what you want to add, and then telling PEAK that your new module
      "inherits" from the generated module.

 Known Issues and Risks of this Version

   This is ALPHA software.  Although much of the system is extensively
   tested by a battery of automated tests, it may contain bugs, especially
   in areas not covered by the test suites.  Also, many system interfaces
   are still subject to change.

   PEAK includes early copies of Zope 3's 'Interface' and 'Persistence'
   packages, which have since changed names in their official releases,
   and have had - and will continue to have - significant implementation
   changes.  Complete interoperability with Zope 3 is therefore currently
   at risk.  We are waiting until the pending refactoring of Zope 3's
   interface package is complete before upgrading from 'Interface' to
   'zope.interface'.  Also, the ZODB persistence package is undergoing
   some changes that may make it less useful for PEAK, and we may be
   forced to "fork" and/or create our own C-level persistence support.
   This may be clearer once ZODB4 and/or Zope 3 reach their next release.

   Documentation at present is limited, and scattered.  The principal
   documentation is an API reference generated from the code's lengthy
   docstrings (which usually contain motivating examples for using that
   class, method, or function).  The mailing list and its archives
   provide a wealth of information on actual usage scenarios,
   recommended approaches, etc.  There is also the beginnings of a
   tutorial on using the component binding package.

 Third-Party Software Included with PEAK

     The 'kjbuckets' module is Copyright Aaron Watters and contributors;
     please see the 'src/kjbuckets/COPYRIGHT.txt' file for details of its

     The 'Interface' and 'Persistence' packages are Copyright Zope Corporation
     and contributors; please see the 'LICENSE.txt' files for details of their

 Installation Instructions

    Please see the INSTALL.txt file.


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