ll-xist 5.14

Extensible HTML/XML generator, cross-platform templating language, Oracle utilities and various other tools

XIST provides an extensible HTML and XML generator. XIST is also a XML parser with a very simple and pythonesque tree API. Every XML element type corresponds to a Python class and these Python classes provide a conversion method to transform the XML tree (e.g. into HTML). XIST can be considered ‘object oriented XSLT’.

XIST also includes the following modules and packages:

• ll.ul4c is compiler for a cross-platform templating language with similar capabilities to Django’s templating language. UL4 templates are compiled to an internal format, which makes it possible to implement template renderers in other languages and makes the template code “secure” (i.e. template code can’t open or delete files).

  There are implementations for Python, Java and Javascript.

• ll.ul4on provides functions for encoding and decoding a lightweight machine-readable text-based format for serializing the object types supported by UL4. It is extensible to allow encoding/decoding arbitrary instances (i.e. it is basically a reimplementation of pickle, but with string input/output instead of bytes and with an eye towards cross-plattform support).

  There are implementations for Python, Java, Javascript and PHP.

• ll.orasql provides utilities for working with cx_Oracle:

  • It allows calling functions and procedures with keyword arguments.

  • Query results will be put into Record objects, where database fields are accessible as object attributes.

  • The Connection class provides methods for iterating through the database metadata.

  • Importing the modules adds support for URLs with the scheme oracle to ll.url.

• ll.make is an object oriented make replacement. Like make it allows you to specify dependencies between files and actions to be executed when files don’t exist or are out of date with respect to one of their sources. But unlike make you can do this in a object oriented way and targets are not only limited to files.

• ll.color provides classes and functions for handling RGB color values. This includes the ability to convert between different color models (RGB, HSV, HLS) as well as to and from CSS format, and several functions for modifying and mixing colors.

• ll.sisyphus provides classes for running Python scripts as cron jobs.

• ll.url provides classes for parsing and constructing RFC 2396 compliant URLs.

• ll.nightshade can be used to serve the output of PL/SQL functions/procedures with CherryPy.

• ll.misc provides several small utility functions and classes.

• ll.astyle can be used for colored terminal output (via ANSI escape sequences).

• ll.daemon can be used on UNIX to fork a daemon process.

• ll.xml_codec contains a complete codec for encoding and decoding XML.

Changes in 5.14 (released 12/02/2015)

• Whitespace handling for UL4 templates has been extended. There are three possible whitespace handling modes now (specified via the new whitespace parameter): "keep" (the old keepws=True) "strip" (the old keepws=False) and the new "smart".

  In smart mode if a line contains only indentation and one tag that doesn’t produce output, the indentation and the linefeed after the tag will be stripped from the text. Furthermore the additional indentation that might be introduced by a for, if, elif, else or def block will be ignored.

  Rendering a template from within another template will reindent the output of the inner template to the indentation of the outer template.

• Rendering an UL4 template from inside a UL4 template is now again done via the <?render?> tag.

• Whitespace handling mode for UL4 templates can now be specified in the template source itself via the <?whitepace?> tag:

  <?whitespace smart?>

• The name and signature of an UL4 template can now be specified in the template source too like this:

  <?ul4 name(x, y, *args, **kwargs)?>

• Closures in UL4 templates no longer see the state of the variables at the time when the local template was defined, but at the time when it is called. This is similar to most other languages that support closures.

• In UL4 tags whitespace is allowed now before the tag name, i.e.:

  <? for i in range(10) ?>
    <? print i ?>
  <? end for ?>

• Exposing attributes of objects to UL4 templates can now be customized via the methods ul4getattr and ul4setattr. Support for making attributes writable or exposing them under a different name via ul4attrs has been removed.

• An object can now be made renderable by UL4 templates by implementing the method ul4render.

• An object can now be made callable by UL4 templates by implementing the method ul4call (__call__ is still supported).

• Stacktraces produced by UL4 templates now include less chained exceptions and are much more informative.

• The rul4 option --keepws has been renamed to --whitespace and defaults to smart now.

• rul4 got a new option --stacktrace: full displays the full Python stack trace, short (the new default) only displays the exception chain without displaying any Python source.

• Templates used in rul4 have access to a new function: import, which can be used to load templates from any file.

• UL4 got two new comparison operators: is and is not for checking for object identity.

• oradd has been renamed to pysql. The commands are now no longer limited to being on one line. Normal SQL commands are now also supported. Normal SQL commands must be terminated with a comment line starting with -- @@@ and PySQL commands must be either on one line, or start with a line containing only { and end with a line containing only }.

  Three new commands have been added: include includes another pysql file. compileall recompiles all objects in the schema and checkerrors raises an exception if there are objects with compilation errors in the schema.

  Also str/bytes values can be loaded from external files via the load class.

• If an identifier is given when invoking a sisyphus job it will be included in the log file name now by default.

• Three new helper functions were added to ll.misc: format_class formats the name of a class object (e.g. ValueError or http.client.HTTPException). format_exception formats an exception:

  >>> misc.format_exception(ValueError("bad value"))
  'ValueError: bad value'

  exception_chain traverses the chain of exceptions (via the __cause__ and __context__ attributes).

• + in the path part of URLs are now considered safe characters. Spaces will be escaped as %20 and no longer as +.

• ll.orasql.Comment has a new method comment that returns the text of the column comment itself.

• The database objects output by ll.orasql.Object.iterreferences and ll.orasql.Oracle.iterreferencedby are now sorted by name to get a stable order of dependencies.

• ll.misc has two new functions: notifystart and notifyfinish. The can be used for issuing Mac OS X notifications.