Merged Utility.py and module enabling docs from 2.3 branch

lib/python/Products/PythonScripts/README.txt

@@ -4,3 +4,56 @@ Python Scripts
   The Python Scripts product provides support for restricted execution of
   Python scripts, exposing them as callable objects within the Zope 
   environment.
+
+  Providing access to extra modules
+
+    Python script objects have a limited number of "safe" modules 
+    available to them by default. In the course of working with Zope,
+    you will probably wish to make other modules available to script
+    objects. 
+
+    The Utility.py module in the PythonScripts products provides a 
+    simple way to make modules available for use by script objects 
+    on a site-wide basis. Before making a module available to Python
+    scripts, you should carefully consider the potential for abuse 
+    or misuse of the module, since all users with permission to 
+    create and edit Python scripts will be able to use any functions
+    and classes defined in the module. In some cases, you may want to
+    create a custom module that just imports a subset of names from 
+    another module and make that custom module available to reduce 
+    the risk of abuse.
+
+    The easiest way to make modules available to Python scripts on 
+    your site is to create a new directory in your Products directory
+    containing an "__init__.py" file. At Zope startup time, this 
+    "product" will be imported, and any module assertions you make
+    in the __init__.py will take effect. Here's how to do it:
+
+      o In your Products directory (either in lib/python of your 
+        Zope installation or in the root of your Zope install,
+        depending on your deployment model), create a new directory
+        with a name like "GlobalModules".
+
+      o In the new directory, create a file named "__init__.py".
+
+      o Edit the __init__.py file, and add calls to the 'allow_module'
+        function (located in the Products.PythonScripts.Utility module),
+        passing the names of modules to be enabled for use by scripts.
+        For example:
+
+          # Global module assertions for Python scripts
+          from Products.PythonScripts.Utility import allow_module
+
+          allow_module('base64')
+          allow_module('re')
+          allow_module('DateTime.DateTime')
+
+        This example adds the modules 'base64', 're' and the 'DateTime'
+        module in the 'DateTime' package for use by Python scripts. Note
+        that for packages (dotted names), each module in the package path
+        will become available to script objects.
+
+      o Restart your Zope server. After restarting, the modules you enabled
+        in your custom product will be available to Python scripts.
+
+        

lib/python/Products/PythonScripts/Utility.py

+##############################################################################
+# 
+# Zope Public License (ZPL) Version 1.0
+# -------------------------------------
+# 
+# Copyright (c) Digital Creations.  All rights reserved.
+# 
+# This license has been certified as Open Source(tm).
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+# 
+# 1. Redistributions in source code must retain the above copyright
+#    notice, this list of conditions, and the following disclaimer.
+# 
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions, and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 
+# 3. Digital Creations requests that attribution be given to Zope
+#    in any manner possible. Zope includes a "Powered by Zope"
+#    button that is installed by default. While it is not a license
+#    violation to remove this button, it is requested that the
+#    attribution remain. A significant investment has been put
+#    into Zope, and this effort will continue if the Zope community
+#    continues to grow. This is one way to assure that growth.
+# 
+# 4. All advertising materials and documentation mentioning
+#    features derived from or use of this software must display
+#    the following acknowledgement:
+# 
+#      "This product includes software developed by Digital Creations
+#      for use in the Z Object Publishing Environment
+#      (http://www.zope.org/)."
+# 
+#    In the event that the product being advertised includes an
+#    intact Zope distribution (with copyright and license included)
+#    then this clause is waived.
+# 
+# 5. Names associated with Zope or Digital Creations must not be used to
+#    endorse or promote products derived from this software without
+#    prior written permission from Digital Creations.
+# 
+# 6. Modified redistributions of any form whatsoever must retain
+#    the following acknowledgment:
+# 
+#      "This product includes software developed by Digital Creations
+#      for use in the Z Object Publishing Environment
+#      (http://www.zope.org/)."
+# 
+#    Intact (re-)distributions of any official Zope release do not
+#    require an external acknowledgement.
+# 
+# 7. Modifications are encouraged but must be packaged separately as
+#    patches to official Zope releases.  Distributions that do not
+#    clearly separate the patches from the original work must be clearly
+#    labeled as unofficial distributions.  Modifications which do not
+#    carry the name Zope may be packaged in any form, as long as they
+#    conform to all of the clauses above.
+# 
+# 
+# Disclaimer
+# 
+#   THIS SOFTWARE IS PROVIDED BY DIGITAL CREATIONS ``AS IS'' AND ANY
+#   EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+#   PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL DIGITAL CREATIONS OR ITS
+#   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+#   USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+#   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+#   OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+#   OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+#   SUCH DAMAGE.
+# 
+# 
+# This software consists of contributions made by Digital Creations and
+# many individuals on behalf of Digital Creations.  Specific
+# attributions are listed in the accompanying credits file.
+# 
+##############################################################################
+"""Utility module for making simple security assertions for
+   Python scripts."""
+
+__version__='$Revision: 1.2 $'[11:-2]
+
+from AccessControl import ModuleSecurityInfo
+import string
+
+def allow_module(module_name):
+    """Allow a module and all its contents to be used from a
+    Python script. The argument module_name may be a simple
+    or dotted module or package name. Note that if a package
+    path is given, all modules in the path will be available."""
+    module  = __import__(module_name)
+    sec_info=ModuleSecurityInfo(module)
+    sec_info.setDefaultAccess(1)
+    sec_info.apply(module.__dict__)
+    for part in string.split(module_name, '.')[1:]:
+        module=getattr(module, part)
+        sec_info=ModuleSecurityInfo(module)
+        sec_info.setDefaultAccess(1)
+        sec_info.apply(module.__dict__)
+