1
0
mirror of https://github.com/scrapy/scrapy.git synced 2025-02-22 14:32:58 +00:00
scrapy/sep/sep-007.rst
2014-03-07 09:27:30 -05:00

138 lines
3.1 KiB
ReStructuredText

======= =============================
SEP 7
Title ItemLoader processors library
Author Ismael Carnales
Created 2009-08-10
Status Draft
======= =============================
======================================
SEP-007: ItemLoader processors library
======================================
This SEP proposes a library of ``ItemLoader`` processor to ship with Scrapy.
date.py
=======
``to_date``
-----------
Converts a date string to a YYYY-MM-DD one suitable for ``DateField``
**Decision**: Obsolete. ``DateField`` doesn't exists anymore.
extraction.py
=============
``extract``
-----------
This adaptor tries to extract data from the given locations. Any
``XPathSelector`` in it will be extracted, and any other data will be added
as-is to the result.
**Decision**: Obsolete. Functionality included in ``XpathLoader``.
``ExtractImageLinks``
This adaptor may receive either XPathSelectors pointing to the desired
locations for finding image urls, or just a list of XPath expressions (which
will be turned into selectors anyway).
**Decision**: XXX
markup.py
=========
``remove_tags``
---------------
Factory that returns an adaptor for removing each tag in the ``tags`` parameter
found in the given value. If no ``tags`` are specified, all of them are
removed.
**Decision**: XXX
``remove_root``
---------------
This adaptor removes the root tag of the given string/unicode, if it's found.
**Decision**: XXX
``replace_escape``
------------------
Factory that returns an adaptor for removing/replacing each escape character in
the ``wich_ones`` parameter found in the given value.
**Decision**: XXX
``unquote``
-----------
This factory returns an adaptor that receives a string or unicode, removes all
of the CDATAs and entities (except the ones in CDATAs, and the ones you specify
in the ``keep`` parameter) and then, returns a new string or unicode.
**Decision**: XXX
misc.py
=======
``to_unicode``
--------------
Receives a string and converts it to unicode using the given encoding (if
specified, else utf-8 is used) and returns a new unicode object. E.g:
::
>> to_unicode('it costs 20\xe2\x82\xac, or 30\xc2\xa3')
[u'it costs 20\u20ac, or 30\xa3']
**Decision**: XXX
``clean_spaces``
----------------
Converts multispaces into single spaces for the given string. E.g:
::
>> clean_spaces(u'Hello sir')
u'Hello sir'
**Decision**: XXX
``drop_empty``
--------------
Removes any index that evaluates to None from the provided iterable. E.g:
::
>> drop_empty([0, 'this', None, 'is', False, 'an example'])
['this', 'is', 'an example']
**Decision**: Obsolete. Functionality included in reducers.
``delist``
----------
This factory returns and adaptor that joins an iterable with the specified
delimiter.
**Decision**: Obsolete. Functionality included in reducers.
``Regex``
----------
This adaptor must receive either a list of strings or an XPathSelector and
return a new list with the matches of the given strings with the given regular
expression (which is passed by a keyword argument, and is mandatory for this
adaptor).
**Decision**: XXX