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version 1633, Sun Jan 25 02:32:15 2004 UTC version 1700, Fri Feb 20 15:24:21 2004 UTC
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   Fixes and Enhancements since Version 0.5 alpha 2
   
    Changed, Enhanced, or Newly Deprecated Features
   
    - Added 'model.Repr' type, useful for doing eval/repr conversions of simple
      Python types, and changed the N2 'htmldump' command to use it.
   
    - Added 'peak.util.mockets', offering imitation socket services like
      'socket()' and 'select()', allowing socket-based services to be tested
      without using real sockets.
   
    - Added limited support for two-phase commit of database connections to Sybase
      and Oracle.  Changed Oracle "outside transaction" semantics to allow read
      operations only, and added a property to set Oracle transactions to
      "serializable" (which effectively requires two-phase commits).  Note that
      the current version of DCOracle2 doesn't properly support two-phase commit
      except for empty (no-op) transactions, which isn't very useful.  However, if
      a later release of DCOracle2 works correctly and doesn't change its API, the
      current PEAK driver should then work correctly.  In the meantime, the
      cx_Oracle driver apparently *does* provide working support for two-phase
      commits.  The controlling properties are of the form 'DRIVER.twoPhaseCommit'
      and 'DRIVER.serializable', where 'DRIVER' is the name of the DBAPI driver
      module, e.g. 'Sybase.twoPhaseCommit' or 'cx_Oracle.serializable'.
   
    - Added properties to the command-line applications framework, allowing
      non-command objects access to 'stdin', 'stdout', 'argv' etc. from their
      context.
   
    - Added '[Named Services]' section parser to 'peak.ini'.  This new section
      type functions similarly to '[Component Factories]', except that
      the keys are property names rather than references to interfaces or other
      component keys, and the values are an expression that creates the actual
      instance, rather than the name of a factory for the service  This should be
      helpful for configuring shared services that all implement the same
      interface, such as SQL connection objects.
   
      Note that to look up a named service, you simply use the appropriate
      property name, as usual.  The difference is that you are guaranteed to
      always use the same *instance* of the service, within a given service area.
   
    - Added 'peak serve' and 'peak launch' commands, for running "CGI" apps in
      a browser from the local machine.  For example, doing this::
   
       PYTHONPATH=examples/trivial_cgi peak launch import:the_cgi.DemoCGI
   
      from the base directory of a PEAK CVS checkout or source distribution will
      launch the 'trivial_cgi' demo program in a new or current browser window.
      Any application runnable with 'peak CGI' should also be runnable with
      'peak serve' or 'peak launch', which makes it very useful for running
      local browser-based apps or testing an application without CGI or FastCGI
      available.  The modules that support this new functionality are
      'peak.util.WSGIServer' (which implements a web server based on Python's
      'BaseHTTPServer', that can run 'running.IRerunnableCGI' objects) and
      'peak.tools.local_server' (which provides PEAK integration.)
   
    - Added 'peak.ddt' framework for Document-Driven Testing.  DDT can parse HTML
      files to extract test descriptions from HTML tables, run the tests, and then
      output an annotated version of the input document, illustrating the results
      by e.g. coloring cells to highlight good/bad results.  To use it, you must
      implement 'ddt.ITableProcessor' components that know how to interpret the
      table contents.
   
    - Added 'fd.file:' URL scheme, for URLs like 'fd.file:stdin' that can be used
      in place of 'file:' URLs for many purposes.
   
    - Added 'model.ExtendedEnum', for enumerations that also support arbitrary
      integers.
   
    - Added 'events.IEventLoop' implementation and refactored 'UntwistedReactor'
      to use it.  'UntwistedReactor' is now nothing more than an adapter from
      'events.IEventLoop' to 'running.IBasicReactor'.  Added 'twisted_support'
      versions of 'peak.events' interfaces (untested).
   
    - 'running.ISignalManager' is now DEPRECATED; please use 'events.ISignalSource'
      instead.
   
    - Added 'events.ISignalSource', that returns 'events.Broadcaster' objects for
      signals.  This allows you to yield to signals in an 'events.Thread', or
      safely set one-time callbacks on them.
   
    - 'running.IMainLoop' has been changed to use an 'events.IReadable' for
      the 'lastActivity' attribute, and the 'setExitCode' and 'childForked'
      methods have been replaced with an 'exitWith()' method.
   
    - The 'peak.running.mainLoop.signalHandler' property has been replaced with
      'peak.running.mainLoop.stopOnSignals', which defaults to including SIGINT,
      SIGTERM, and SIGBREAK.  If you need custom signal handling, please use
      the event sources provided by an 'events.ISignalSource'.
   
    - Simplified configuration for using Twisted, roughly as proposed in
      "this message.":http://www.eby-sarna.com/pipermail/peak/2004-January/001125.html
   
      You can now configure a service area as using Twisted by setting its
      'peak.events.isTwisted' property, or by depending upon the
      'running.ITwistedReactor' interface, as long as it happens early enough.
   
      If you need to make choices based on whether a Twisted reactor is being
      used, you should use the 'events.ifTwisted()' function.  If you would like
      to try to force a service area to use a Twisted reactor, you may use
      'events.makeTwisted()'.
   
    - Added automatic installation of 'csv' module for Python < 2.3.
   
    - Added 'peak.events' package, supporting a simple event-driven programming
      microkernel, including event-driven "ultralight" threads powered by
      generators.
   
    - "Global" services defined by '[Component Factories]' sections now live in
      the closest "service area" to the component that requests them.  A "service
      area" is a parent component that implements 'config.IServiceArea', such as
      a configuration root returned by 'config.makeRoot()'.  Applications loaded
      by the 'peak runIni' command are now created in their own service area,
      which means that settings in the .ini file being run will apply to services
      the application uses.  (Because the application will have its own,
      application-specific service instances, and they will use the configuration
      loaded into the service area.)
   
      If you need to create your own service area, you can do so by mixing in
      'config.ServiceArea' to your component class.  However, you should *not* do
      this unless you know exactly what "outside" services you may need to use
      from "inside" the newly created service area, so that you can explicitly
      connect them "into" the service area.  (In short, if you don't know *why*
      you're creating a service area, don't do it.)
   
    - 'config.Namespace()' objects now have a 'keys()' method that can be used
      when the namespace is bound to a context component.  It returns a list of
      strings that may be used as keys for that namespace.  Example usage::
   
       >>> from peak.api import *
       >>> r=config.makeRoot()
       >>> ns=config.Namespace('peak.naming.schemes',r)
       >>> ns.keys()
       ['https', 'smtp', 'logfile', 'psycopg', 'pkgfile', 'unix.dg', 'win32.dde',
       'sybase', 'timer', 'lockfile', 'pgsql', 'fd.socket', 'uuid', 'tcp', 'file',
       'gadfly', 'http', 'logger', 'icb', 'cxoracle', 'udp', 'winflockfile',
       'import', 'logging.logger', 'nulllockfile', 'nis', 'shlockfile',
       'zconfig.schema', 'flockfile', 'shellcmd', 'dcoracle2', 'config', 'ftp',
       'unix', 'ldap', 'sqlite', 'mockdb']
       >>> ns['ldap']
       'peak.storage.LDAP:ldapURL'
   
    - Log events don't use a positional 'message' argument any more, and
      loggers aren't responsible for interpolating message arguments any more.
      The new signature is 'Event(parent, msg=msg, args=args, ...)'.  Loggers
      also now tell events what logger name they are, via the 'ident' keyword.
   
    - The logging system now uses a property namespace, 'peak.logging.levels', to
      obtain log level names and values.  The various 'logs.LEVEL' constants are
      now DEPRECATED.  Please use the 'getLevelFor()' method of the nearest
      'logs.ILoggingService' instead.  Also note that URL schemes such as
      'logfile:' no longer convert their level names to numbers, since the
      level names are only meaningful in the context of a logging service.
   
    - Support for integration with the Python 2.3/PEP 282 logging module has been
      scaled back.  There are too many globalisms and dependencies there.  When we
      add plugin-based log configuration, it should be possible to use the logging
      package's handlers and formatters with the PEAK logging services.  At that
      point, you'll be able to replace 'logging.getLogger' and
      'logging.getLevelName' with the corresponding methods of a PEAK logging
      service, if you need to force non-PEAK packages to use PEAK's logging.
   
    - Logs are now accessed via a 'logs.ILoggingService' instance.  The 'logger:'
      URL scheme automatically accesses the nearest such service.  For backward
      compatibility, the old 'peak.logs' namespace is still used to supply the
      actual loggers.  This will be gradually replaced with a plugin-based
      mechanism.
   
    - Added 'binding.PluginKeys' and 'binding.PluginsFor'.  These are component
      keys that can be used to 'Obtain' plugins registered within a property
      namespace.  'PluginKeys' obtains a list of the plugins' configuration keys,
      while 'PluginsFor' obtains a list of the actual plugins.
   
    - Replaced 'peak.config.registries.EigenRegistry' with
      'peak.config.registries.ImmutableConfig'.  The only use we had for
      'EigenRegistry' was to keep track of 'offerAs' settings within classes, and
      it didn't need all the extra complexity of eigenstate management.  The new,
      more-specialized class is shorter, simpler, and easier to use.
   
    - Added 'config.iterKeys()' which iterates over all available configuration
      keys in a given namespace (just property names for now).  The 'config:'
      namespace is now a 'naming.IReadContext', so you can navigate it with the
      'n2' command, and do things like 'ls -l config:peak.naming.schemes' to list
      all configured naming schemes.
   
    - Added 'config.parentProviding()' and 'config.parentsProviding()', which
      find the first (or all) parent components of a given component that support
      a given protocol.
   
    - Renamings/refactorings/deprecations in 'peak.config':
   
       'config.getProperty' -- use 'config.lookup()' instead
   
       'config.findUtility' -- use 'config.lookup()' instead
   
       'config.findUtilities' -- use 'config.iterValues()' instead
   
       'config.IPropertyMap' -- use 'config.IConfigMap' or 'config.IConfigurable'
   
       'config.PropertyMap' -- use 'config.ConfigMap' instead
   
       'config.setPropertyFor' -- DEPRECATED, see source for replacement code.
   
       'config.setRuleFor' -- DEPRECATED, see source for replacement code.
   
       'config.setDefaultFor' -- DEPRECATED, see source for replacement code.
   
       'config.instancePerComponent' -- DEPRECATED, use factories instead.
   
       'config.IConfigurationRoot' -- interface has changed; 'propertyNotFound' is
       no longer a method, and 'noMoreUtilities' is now 'noMoreValues'.
   
       'exceptions.PropertyNotFound' -- use 'exceptions.NameNotFound' instead.
   
       'exceptions.OutOfScope' -- REMOVED; it was not actually used in PEAK.
   
      In all cases, the old interface, class, or function is DEPRECATED and will
      go away in the alpha 4 release cycle.  Please take particular note of the
      fact that 'IConfigMap' offers virtually none of the convenience
      methods provided by 'IPropertyMap', so adjust your code accordingly.  Note
      also that even though there are plenty of references to 'IPropertyMap'
      remaining in PEAK itself, these are strictly to provide backward
      compatibility.  Once we enter the alpha 4 release cycle, these will go away.
   
    - Added 'config.MultiKey()' and 'config.UnionOf()' configuration key classes,
      to generalize existing specialty keys such as 'ProviderOf' and 'FactoryFor'.
      (The latter two are now defined in terms of the former two.)  Also, made
      classes and types usable as configuration keys.  This was needed for the
      above generalization, but also makes many other class-lookup concepts
      possible.  (Note that there may be some slight changes to the effective
      registration and lookup order of these and other configuration keys as of
      this change, as there were some previous errors and/or ambiguities to the
      lookup order that were not covered by the test suite.)
   
    - Added "[Import on Demand]" section type to .ini files, allowing you to
      define shortcuts for modules that you frequently reference in your
      configuration.  This lets you replace e.g. 'importString("foo.bar.baz:Spam")'
      with 'foo_baz.Spam' in expressions, by adding something like this::
   
       [Import on Demand]
       foo_bar = "foo.bar.baz"
   
      to your configuration.  The defined shortcut is then available for the
      remainder of that configuration file, and in any .ini files included from
      the current file.  See 'peak.ini' for an example and more info.
   
    - Logging-related interfaces have been moved into the 'peak.running.logs'
      module.  So, what used to be 'running.ILogger' is now 'logs.ILogger'.
   
    - Log events now use a standard component construction signature, and the
      class used for event objects is now configurable as the factory for
      'logs.ILogEvent'.  (See "[Component Factories]" in 'peak.ini'.)
   
    - By popular demand, 'logs.ILogger' (and its default implementation) now
      includes 'trace()', 'notice()', 'alert()' and 'emergency()' methods that use
      the corresponding 'syslog' priority levels.  'logs.IBasicLogger' has been
      added, to reflect the narrower interface provided by PEP 282, and there is
      an adapter that can extend PEP 282 loggers with the other methods.
   
    - The 'logging.logger:' URL scheme has been simplified to 'logger:'.  Please
      convert your scripts and configuration files, as the longer form will go
      away in the alpha 4 development cycle.
   
    - Added 'commands.lookupCommand()' to look up a command shortcut or URL, ala
      the 'peak' script or 'commands.Bootstrap' class.  Also added various
      'commands.ErrorSubcommand' subclasses to make it easier to issue errors
      from/for subcommands.
   
    - Added 'peak.core' as a minimal subset of 'peak.api'.  'peak.core' offers
      only "core" API packages and primitives, not the full set of available
      framework APIs.  'peak.api' will continue to expand as frameworks are added,
      but 'peak.core' will stay as small as practical.  ('peak.exceptions' may in
      fact end up being removed from 'peak.core', or at least renamed.)
   
    - Added 'peak.util.symbol' module, to contain 'NOT_GIVEN', 'NOT_FOUND', and
      the 'Symbol' class used to create them.
   
    - 'peak.running.tools' was promoted to 'peak.tools'.  'peak.running.supervisor'
      was also moved to 'peak.tools.supervisor', and a new 'peak help' command was
      added in 'peak.tools.api_help'.
   
    - Replaced the "[Provide Utilities]" section of .ini files with "[Component
      Factories]".  The new section type is easier to use, much more versatile,
      and does all registration and imports lazily.  See the 'peak.ini' file for
      docs.  "[Provide Utilities]" and 'config.ProvideInstance()' are now
      DEPRECATED, so please convert ASAP.
   
    - 'binding.Make()' now accepts configuration keys, using them to look up a
      factory object that's then invoked to create the attribute.  This makes it
      a lot easier to define a component with its own transaction service
      or other normally "global" component.  It also makes it easier to globally
      specify a factory class for some interface.  Factories are looked up under
      the 'config.FactoryFor(key)' configuration key.  (See below.)
   
    - Added 'config.FactoryFor(key)', a 'config.IConfigKey' implementation that
      provides a configuration namespace for factories.
   
      When you use 'binding.Make(ISomething)', it's roughly equivalent to::
   
           binding.Make(
               lambda self,d,a:
                   binding.lookupComponent(
                       self, config.FactoryFor(ISomething),
                       adaptTo = binding.IRecipe
                   )(self,d,a)
           )
   
      That is, the 'config.FactoryFor(ISomething)' is looked up and invoked.
   
    - Added 'config.CreateViaFactory(key)', a 'config.IRule' implementation that
      creates an implementation of 'key', by looking up 'config.FactoryFor(key)'
      and invoking it.
   
    - Added 'config.ruleForExpr(name,expr)', that returns a 'config.IRule' that
      computes the Python expression in the string 'expr'.  This is the mechanism
      used by configuration files to create rules, factored out into an API call
      so that configuration extensions can use it, too.
   
    - The 'referencedType' of a 'model.StructuralFeature' can now be any
      'binding.IComponentKey', not just a type or a string.  Types are also now
      implicitly component keys, which means you can use 'binding.Obtain(SomeType)'
      to look up 'SomeType'.  (Right now, this is no different than using 'SomeType'
      without the 'binding.Obtain()', but in future releases this will use a
      "class replacement service" to allow easy replacement of model and other
      collaborator classes, while implementing AOP-like features.)
   
    - Added 'naming.Indirect(key)', a 'binding.IComponentKey' that can be used to
      do an indirect lookup via another 'IComponentKey' (such as a name).
   
      Using 'naming.Indirect()', you can replace code like this::
   
           socket = binding.Obtain(
               lambda self: self.lookupComponent(self.socketURL),
               adaptTo=[IListeningSocket]
           )
   
      with code like this::
   
           socket = binding.Obtain(
               naming.Indirect('socketURL'), adaptTo=[IListeningSocket]
           )
   
    - Added 'peak.tools.supervisor', a mini-framework for pre-forking,
      multiprocess servers, such as for FastCGI.  The framework includes a ZConfig
      schema for process supervisors, and support for automatically forking new
      children (up to a predefined maximum, with a minimum interval between
      launches) when a socket has pending connections and all of its child
      processes are busy.  With this setup, you can take more advantage of
      multiprocessor machines for CPU-intensive services.
   
    - Standardized these characteristics of name and address syntax:
   
      * '//' at the beginning of URL bodies is *mandatory* when the URL begins
        with an "authority" as described by RFC 2396.  When the URL is not
        required to contain an authority (e.g. 'peak.storage.SQL.GenericSQL_URL'),
        the '//' is *optional*, and the canonical form of the URL will not include
        it.
   
      * Standardized names for RFC 2396 fields: 'user', 'passwd', 'host', and
        'port'.
   
    - Added 'peak.metamodels.ASDL', a metamodel for the Zephyr Abstract Syntax
      Description Language.  ASDL is a convenient way to describe a domain model
      for an abstract syntax tree (AST), and the models generated with the new
      ASDL tool can be combined with concrete syntax to create a complete parsing
      solution for "mini languages", possibly including the Python language
      itself.  (Future versions of the Python and Jython compilers are likely to
      use AST models based on ASDL, and in the current Python CVS sandbox there's
      already an ASDL model of Python's AST available.)
   
    - Enhanced 'fmtparse' and 'peak.model' to allow using types as syntax rules
      for parsing, including abstract types.  An abstract type's syntax is the
      union (using 'fmtparse.Alternatives') of the syntaxes of its subclasses
      (as specified by 'mdl_subclassNames').
   
    - Added 'IMainLoop.exitWith()' method, to allow reactor-driven components to
      control the mainloop's exit code.
   
    - Added 'IBasicReactor.crash()', which forces an immediate reactor loop exit,
      ignoring pending scheduled calls.
   
    - Added 'peak.running.commands.runMain()', a convenience function for starting
      an application's "main" command, that also makes it easy for forked child
      processes to exit and replace the parent process' "main".  The 'peak' script
      has now been shortened to::
   
          from peak.running import commands
          commands.runMain( commands.Bootstrap )
   
      so it's now much easier to create alternative startup scripts, if you need
      to, or to add an 'if __name__=="__main__"' clause to a module.
   
    - Added 'peak.util.mockdb', a "mock object" implementation of a DBAPI 2.0
      driver module.  'mockdb' connections can be told to 'expect()' queries
      and 'provide()' data to their callers, and will raise AssertionErrors when
      they are used in a way that doesn't conform to your supplied expectations.
      This is intended to be used for unit testing components that depend on
      a database connection: you can verify that they send the right SQL, and
      you can provide them with dummy data to use.  There is also a 'mockdb:' URL
      and peak.storage driver, so you can easily use a mock DB connection in place
      of a real one within a PEAK application, for testing purposes.  Note,
      however, that 'peak.util.mockdb' is a DBAPI 2.0 driver in itself, and thus
      can also be used to test DBAPI usage outside of PEAK.
   
    - SQL connection objects now provide an 'appConfig' attribute that is a
      driver-specific 'config.Namespace()'.  This allows you to easily set up
      configuration properties that are driver-specific.  For example, you could
      use properties to configure driver-specific SQL snippets, then access them
      via the connection's 'appConfig' namespace.  The namespaces are of the form
      'DRIVER.appConfig', where 'DRIVER' is the name of the DBAPI module for that
      connection type (e.g. 'pgdb', 'cx_Oracle', etc.).
   
    - Added 'config.Namespace()' convenience class for redirecting property
      lookups from one namespace to another.  See the docstring and 'peak.ini' for
      usage examples.  'PropertyName.of()' now returns 'Namespace' instances
      instead of 'PropertySet' instances.
   
    - DEPRECATED the 'config.PropertySet' class; please convert to using
      'config.Namespace', as 'PropertySet' will disappear in the 0.5alpha4 release
      cycle.
   
    - SQL connection objects now get their type converters from a distinct
      property namespace for each DBAPI driver.  For example a driver using the
      'cx_Oracle' module will get its type converters from the
      'cx_Oracle.sql_types' property namespace, instead of 'peak.sql_types'.  For
      backward compatibility, these driver-specific namespaces are set up to
      fall back to 'peak.sql_types' for their defaults.  Type converter
      construction has also been improved, to eliminate conversion overhead
      completely when no conversions are required for a specific query.  Also,
      SQL connections now offer a method that will create a row conversion
      function for a given result description and optional postprocessing
      function.  This new method should now be used in place of direct access to
      the 'typeMap' attribute of connection objects.
   
    - Added 'binding.Require', 'binding.Obtain', 'binding.Make', and
      'binding.Delegate'.  *ALL* other binding types are now DEPRECATED, and will
      go away before 0.5 beta is released:
   
      'requireBinding("info")' -- use 'Require("info")'
   
      'delegateTo("attr")' -- use 'Delegate("attr")'
   
      'New(type)' -- use 'Make(type)'
   
      'New("module.type")' -- use 'Make("module.type")'
   
      'bindTo(key)' -- use 'Obtain(key)'
   
      'Constant(value)' -- use 'Make(lambda: value)'
   
      'Acquire(key)' -- use 'Obtain(key, offerAs=[key,])'
   
      'Copy(value)' -- use 'Make(lambda: <expr to copy value>)'
   
      'whenAssembled(func)' -- use 'Make(func, uponAssembly=True)'
   
      'bindSequence(key1,key2,...)' -- use 'Obtain([key1,key,...])'
   
      'bindToProperty(x,y)' -- use 'Obtain(PropertyName(x),default=y)'
   
      'bindToParent()' -- use 'Obtain("..")'
   
      'bindToSelf()'  -- use 'Obtain(".")'
   
      'bindToUtilities()' -- no replacement; let me know if you're using this.
   
      Note that 'Make' and 'Obtain' also support sequences of recipes and keys,
      and in those cases will produce a sequence of the results from those recipes
      or keys.  Also, 'Make' will accept no-argument and one-argument callables,
      where 'Once' always required three-argument functions.  This should make it
      a lot easier to write short binding functions.
   
      Also, note that the 'activateUponAssembly' keyword is now 'uponAssembly',
      and 'isVolatile' is now 'noCache'.  (The old names will work as keyword
      arguments until the alpha 4 development cycle begins.)  The
      'binding.IActiveDescriptor' interface also changed as a result of this.
      Last, but not least, a 'binding.IRecipe' interface was added, to support the
      new 'binding.Make' type.
   
   
    - Added a 'lockName' attribute to 'runnning.AdaptiveTask', and a 'LockURL'
      setting to its ZConfig schema.  This allows a lockfile URL to be specified
      for adaptive tasks that need exclusive access to some resource while
      running.
   
    - A list or tuple of 'IComponentKey' instances is now treated as a single
      component key, that returns a tuple of the values returned by each
      constituent component key.  This means that 'binding.Obtain()' and
      'lookupComponent()' can now accept a list or tuple of component keys.  This
      makes 'bindSequence()' obsolete, so 'bindSequence()' is now DEPRECATED.
      'binding.bindSequence(key1,key2,...)' can now be replaced with
      'binding.Obtain([key1,key,...])', and will produce the same results.
   
    - 'naming.IBasicContext.lookup()' and 'naming.lookup()' now accept a 'default'
      argument, similar to that used by 'lookupComponent()' and most other
      lookup-like APIs in PEAK.  This change was made so that component lookups
      don't need to rely on catching 'exceptions.NameNotFound' errors to tell them
      when to use the default value.  This could hide 'NameNotFound' errors that
      were actually from a broken component somewhere in the lookup process.  (In
      general, it's probably a bad idea to have an exception that's used for both
      control flow and real errors!)
   
    - Added new 'version' tool that automatically edits files to update version
      information in them.  Just execute the 'version' file in the main PEAK
      source directory.  (Use '--help' for help.)  You can use this tool with your
      own projects by creating 'version' and 'version.dat' files in your project
      directory, similar to the ones used by PEAK.  The 'version' file is a ZConfig
      file that describes your project's version numbering scheme(s), formats,
      and the files that need to be edited, while the 'version.dat' file contains
      the current version number values.  Source for the tool, including the
      configuration file schema, is in the 'peak.tools.version' package.
      (Error handling and documentation, alas, are still minimal.)
   
    - Added new 'Alias' command in 'peak.running.commands'.  An 'Alias' instance
      can be used as a 'peak.running.shortcut' property that expands to another
      command with arbitrary arguments inserted before the original command's
      arguments.  Thus, one might alias 'mycommand' to 'runIni somefile --option',
      similar to command aliases in many shells.
   
    - 'naming.IName' is now derived from 'binding.IComponentKey', so names and
      addresses must now support the 'findComponent()' method.  All PEAK name and
      address types provide support for this.
   
    - The 'lookup()' method of 'binding.IComponentKey' is now called
      'findComponent()', to better distinguish it from 'lookup()' in
      'naming.IBasicContext', which does something very different.
   
    - 'binding.Obtain()' (formerly 'binding.bindTo()' and 'binding.bindSequence()')
      now pre-adapt their arguments to 'IComponentKey', to speed up lookups at
      runtime, and to ensure that errors due to an unusable parameter type occur
      at class creation time instead of waiting until lookup time.
   
    - There's a new 'peak.storage.files' module, with handy classes like
      'EditableFile'.  'EditableFile' is a class that lets you edit the contents
      of a file "in place", with atomic replacement of the original at transaction
      commit.  If the transaction is aborted, the original file is left unchanged.
   
    - 'peak.running.scheduler.UntwistedReactor' now supports a configuration
      property ('peak.running.reactor.checkInterval') to determine how long it
      should run 'select()' calls for, when there are no scheduled tasks.
   
    - 'peak.running.commands.AbstractCommand' now offers a '_run()' method that
      can be overridden in subclasses, instead of 'run()'.  If you override the
      new '_run()' method instead, you get the advantage of automatic handling
      for invocation errors and 'SystemExit' exceptions, provided for you by the
      'run()' method.
   
    - There is now a 'storage.DMFor(class)' function that returns a configuration
      key for registering or looking up data managers by class.  You can use the
      returned key in a binding's 'offerAs' list, or as the target of a 'bindTo()'
      or 'lookupComponent()'.  The key is constructed using
      'config.ProviderOf(storage.IDataManager,class)'.
   
    - You can now register utilities that are keyed by the combination of an
      interface and one or more classes, using 'config.ProviderOf(iface,*classes)'
      as a configuration key.  Providers are registered under an '(iface,klass)'
      tuple for each specified class, and looked up using the MRO order of the
      class specified for lookup.  In other words, searching for a provider will
      find a provider for the requested class, or one of its base classes, with
      precedence given to the more-specific provider.  This is primarily intended
      for services like data managers and Specialists.
   
    - It's now possible to extend .ini file parsing with custom section types,
      and PEAK defines its own built-in section types using this extension
      mechanism.  Custom section types must include at least one space, (e.g.
      '[My Section]') or they will be treated as a plain property name.
      See the 'peak.config.iniFile.sectionParsers' section in 'peak.ini' for
      more details, along with the 'config.ISettingParser' and 'config.IIniParser'
      interfaces.
   
    - When creating a 'PropertyName()', it's now possible to force conversion of
      invalid characters to '_', using the 'PropertyName.fromString()'
      constructor.  (Note that the input must be a plain-ASCII string.)  Unless
      you request that wildcards ('?' and '*') be kept, they will also be
      converted to '_' characters.  This can be convenient for converting things
      like filenames or text that might contain spaces, to property names.
   
    - It's now possible to declare an attribute as offering a wildcard property;
      such lookups now follow the same rules as other wildcard property lookups.
      The 'config.IConfigKey' interface has been changed to cleanly support
      implied keys at both registration and lookup time, so you can implement
      your own key types that work the way interfaces or property names do for
      configuration lookups.
   
    - The 'EigenRegistry' class has been moved from 'peak.util.EigenData' to
      'peak.config.registries', as it hasn't really been useful outside PEAK for
      a while now.
   
    - .ini files now support "smart property" objects ('config.ISmartProperty').
      If a property rule defined in an .ini file evaluates at runtime to an object
      that implements 'ISmartProperty', the object will be given a chance to
      compute a value for the property, in place of being used itself.  This helps
      to simplify definition of complex property rules in .ini files, by allowing
      the use of helper classes.  Also, 'naming.LinkRef' and 'naming.Reference'
      (indirectly) support this interface, so you can now use them in .ini files
      to refer to an object via the naming system.  (Previously, 'naming.LinkRef'
      wouldn't do the right thing unless the property was looked up via a
      'config:' URL, and 'naming.Reference' didn't exist.)
   
    - 'peak.util.imports.whenImported()' can now be used even when the specified
      module has already been loaded.
   
    - The naming system no longer has 'objectFactories' and 'stateFactories' as
      utilities; they have been replaced with new mechanisms involving adaptation.
      Previously, addresses had a 'retrieve()' method that could be used to
      retrieve the object defined by the address.  Now, to retrieve an object for
      an address, you must either define a context that processes the address, or
      the address must have a 'defaultFactory' attribute, which provides a name
      to be imported to get an 'IObjectFactory' that can construct the referenced
      object.  (This is simpler than it sounds; for URLs that reference
      ManagedConnections, for example, all you need to do is provide the fully
      qualified name of the connection class.)
   
      Meanwhile, writable naming contexts must have a 'serializationProtocol'
      attribute, specifying what interface an object should be adapted to before
      attempting to store it in that context.
   
      The naming system no longer processes the 'creationName' keyword argument;
      this is now considered the sole responsibility of 'peak.binding'.  The
      'IComponent.lookupComponent()' method still accepts the keyword argument,
      and attribute bindings still handle the creation name transparently.  It is
      just not available via naming system APIs, and naming contexts no longer
      have to deal with it.
   
      The naming system base classes no longer use 'attrs' as an input parameter
      or return value.  If you've subclassed anything from 'peak.naming.contexts',
      note that your '_get()' methods should now just return the lookup value,
      rather than a 'state,attrs' tuple.  For most naming contexts, this just
      means you should change 'return foo, None' statements to just 'return foo'.
   
    - Property definition rules in an .ini file can now refer to 'rulePrefix' and
      'ruleSuffix' variables.  'rulePrefix' is a "."-terminated string,
      representing the name the rule was defined with.  For example, if the
      rule was defined for '"foo.bar.*"', then 'rulePrefix' will be '"foo.bar."'
   
      The 'ruleSuffix' will be the portion of the 'propertyName' that follows
      'rulePrefix'.  So, if looking up property '"foo.bar.baz"', then the
      '"foo.bar.*"' rule will execute with a 'ruleSuffix' of '"baz"'.  This should
      make it easier to work with hierarchical property namespaces.
   
    - Added simple example scripts and small applications in the 'examples'
      directory.
   
    - There is a new command-line namespace introspection tool, 'n2', which
      can be accessed by running 'peak n2'.  Type 'peak n2 -h' for help.
   
    - The PEAK_CONFIG environment variable can now list multiple files, separated
      by the platform's 'os.pathsep' (e.g. ':' on Unix, ';' on Windows).
   
    - It's no longer necessary to provide a '_defaultState()' implementation
      for an EntityDM: a default implementation is now supplied.
   
    - Added automatic installation of 'datetime' package for Python < 2.3.
   
    - CGI support has been moved from 'peak.running.zpublish' into
      'peak.running.commands' (for "raw" CGI/FastCGI) and 'peak.web' (for the
      PEAK high-level publishing framework).  You can use 'peak CGI someName' to
      adapt 'someName' to a 'running.IRerunnableCGI' and run it as a CGI/FastCGI.
   
    - There is now a 'peak.security' package, available from 'peak.api' as
      'security'.  It provides permission management functions: you can define
      abstract permissions by subclassing 'security.Permission', then create
      permission checking rules by subclassing 'security.RuleSet', and declare
      the permissions needed to access attributes of a class with
      'security.allow()'.  The test suite demonstrates a complex application
      ruleset with dynamic, data-driven permissions.
   
    - There is now an interface for "Active Descriptors":
      'binding.IActiveDescriptor'.  'peak.binding' now uses this interface to
      identify active descriptors, so you can now create your own.  (Previously,
      'peak.binding' used 'isinstance()' to detect active descriptors.)
   
    - REMOVED 'naming.ParsedURL'; it was deprecated as of 0.5 alpha 2.
   
    - The 'provides' keyword argument to various 'peak.binding' APIs has been
      renamed to 'offerAs', and it must be a sequence of configuration keys.
      (Previously, it accepted either a single key or a tuple of keys.)
      The signature of 'binding.Constant()' was changed as well; the first
      positional argument is now the constant value, and 'offerAs' is now a
      keyword argument.  (Previously, 'provides' was the first positional argument
      of 'binding.Constant()'.)  The 'registerProvider()' method of
      'config.IConfigurable()' also now accepts only a single configuration key,
      as does 'EigenRegistry.register()'.
   
      Also, all 'peak.binding' APIs now only accept positional parameters for
      items unique to that API.  Items common to multiple APIs (such as 'offerAs',
      'doc', 'attrName', etc.) should now be supplied as keyword arguments.
   
      Bindings also now automatically "suggest" the containing object as a parent
      component for the contained object, whenever a value is assigned to them or
      computed.  If a non-None 'adaptTo' is set on the binding, the value assigned
      or computed will be adapted to the specified protocol before the parent
      component is suggested.  'binding.New()' no longer relies on the
      'IComponentFactory' interface, but instead uses the new adapt/suggest
      mechanisms.
   
      Previously, parent components were only "suggested" when a binding was set
      via component constructor keyword arguments.  Now, this is done at any time
      bindings are set, but *not* for non-binding keyword arguments.  In other
      words, ordinary attributes of a component do not receive "suggested parent"
      notices, even when set via constructor keyword arguments.  If you want an
      attribute to do this, you must define the attribute with the binding API;
      e.g. via 'requireBinding()' or 'binding.Constant()'.  If you do *not* want
      a binding to suggest a parent component, use 'suggestParent=False' in the
      binding definition.
   
    Corrected Problems
   
     - 'peak.running.commands.CGICommand' could become confused on certain BSD
       variants (such as Mac OS/X), and assume it was running under FastCGI, even
       if it wasn't.  (Because the operating systems in question use socket pairs
       to implement pipes.)
   
     - Fixed some problems with the test suite when running under Python 2.3.
       PEAK itself worked fine, but the test suite was bitten by two minor
       semantic changes that took effect in 2.3, resulting in lots of error
       messages about ModuleType needing a parameter, and a test failure for
       'checkClassInfo' in the 'FrameInfoTest' test class.
   
     - Transaction participants that raised an error in their 'abortTransaction()'
       method, would not receive a 'finishTransaction()' call, the error was
       passed through to the transaction service's caller, and later participants
       might not have received an 'abortTransaction()' message either.
   
     - SQL connections didn't close their cursors before aborting a transaction
   
     - The logging system would raise an error if a log message with no arguments
       contained a '%' sign.
   
     - There was a typo in peak.naming.arithmetic that caused homogeneous non-URL
       name subtraction to fail.
   
     - The default reactor supplied in 'peak.running.scheduler' would consume
       CPU continuously if it was waiting for I/O and no tasks were scheduled.
   
     - The 'peak.util.imports.whenImported' function didn't work.
   
   
 Fixes and Enhancements since Version 0.5 alpha 1  Fixes and Enhancements since Version 0.5 alpha 1
   
  Changed, Enhanced, or Newly Deprecated Features   Changed, Enhanced, or Newly Deprecated Features


Generate output suitable for use with a patch program
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Removed from v.1633  
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  Added in v.1700

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