Manipulator section

A manipulator pipeline section lets you copy, move or discard keys from the pipeline. The manipulator section blueprint name is collective.transmogrifier.sections.manipulator.

A manipulator section will copy keys when you specify a set of keys to copy, and an expression to determine what to copy these to. These are the keys and destination options.

The keys option is a set of key names, one on each line; keynames starting with re: or regexp: are treated as regular expresions. The destination expression is a TALES expression that can access not only the item, but also the matched key and, if a regular expression was used, the match object.

If a delete option is specified, it is also interpreted as a set of keys, like the keys option. These keys will be deleted from the item; if used together with the keys and destination options, keys will be renamed instead of copied.

Also optional is the condition option, which lets you specify a TALES expression that when evaluating to False will prevent any manipulation from happening. The condition is evaluated for every matched key.

>>> manipulator = """
... [transmogrifier]
... pipeline =
...     source
...     copy
...     rename
...     delete
...     logger
...
... [source]
... blueprint = collective.transmogrifier.sections.tests.samplesource
...
... [copy]
... blueprint = collective.transmogrifier.sections.manipulator
... keys =
...     title
...     id
... destination = string:$key-copy
...
... [rename]
... blueprint = collective.transmogrifier.sections.manipulator
... keys = re:([^-]+)-copy$
... destination = python:'%s-duplicate' % match.group(1)
... delete = ${rename:keys}
...
... [delete]
... blueprint = collective.transmogrifier.sections.manipulator
... delete = status
...
... [logger]
... blueprint = collective.transmogrifier.sections.logger
... name = logger
... level = INFO
... """
>>> registerConfig('collective.transmogrifier.sections.tests.manipulator',
...                manipulator)
>>> transmogrifier('collective.transmogrifier.sections.tests.manipulator')
>>> print(handler)
logger INFO
    {'id': 'foo',
    'id-duplicate': 'foo',
    'title': 'The Foo Fighters ℗',
    'title-duplicate': 'The Foo Fighters ℗'}
logger INFO
    {'id': 'bar',
    'id-duplicate': 'bar',
    'title': 'Brand Chocolate Bar ™',
    'title-duplicate': 'Brand Chocolate Bar ™'}
logger INFO
    {'id': 'monty-python',
    'id-duplicate': 'monty-python',
    'title': "Monty Python's Flying Circus ©",
    'title-duplicate': "Monty Python's Flying Circus ©"}
>>> handler.clear()

The destination expression has access to the following:

item	the current pipeline item
key	the name of the matched key
match	if the key was matched by a regular expression, the match object, otherwise boolean True
transmogrifier	the transmogrifier
name	the name of the splitter section
options	the splitter options
modules	sys.modules