def __init__(self, csspath=None, xpath=None, idname=None):
from mobilize.util import classvalue
from mobilize.filters import noimgsize
assert not (csspath is None and xpath is None), 'You must provide either a csspath or an xpath!'
if xpath is None:
xpath = _csspath2xpath(csspath)
kwargs = dict(
classvalue = classvalue('bigimage'),
postfilters = [noimgsize],
)
if idname is not None:
kwargs['idname'] = idname
super().__init__(xpath, **kwargs)
def __init__(self,
selector,
filters=None,
prefilters=None,
postfilters=None,
omitfilters=None,
classvalue=None,
idname=None,
style='',
filtermode=FILT_EACHELEM,
usecopy=False,
tag='div',
innerhtml=False,
keep_if=None,
):
'''
ctor
The selector's job is to unambiguously specify which part of
the source document to extract. Its exact syntax and meaning
depends on the subclass. For example, it could be an xpath
expression, a CSS "path", etc.
In general, the selector may actually be plural, i.e. some
iterable of individual selectors. The effect, again depending
on the subclass, will be to the matches of each selector
together.
SPECIFYING FILTERS
Before final rendering, zero or more filters will be applied
to the extracted content. By "filter", we mean some callable
that conforms to the Mobilize filter API; read the docs of
mobilize.filters for details. Since each filter may transform
the HTML snippet in an arbitrary way, the order matters.
The filters, prefilters, postfilters, and omitfilters
arguments all allow you to control what filters are applied to
the extracted content. Each argument is optional, and if
supplied, is a collection of filter-api callables. By default,
filters.DEFAULT_FILTERS are set to be applied. If you specify
prefilters, that list is prepended to the default list;
likewise, postfilters is appended to the default. If you
specify filters, that will *replace* the default.
omitfilters is a set of filters, or some sequence convertable
to a set (with the set() constructor). If you specify
omitfilters, any filters within (identified by Python's id())
will be removed from the default list. This is convenient if
you want to use all default filters except one or two for a
component, in a forward-compatible way.
If you use the filters argument, you cannot specify
prefilters, postfilters or omitfilters. You can use one or
more of prefilters, postfilters or omitfilters, but then
cannot use filters. To specify that no filters are to be used
at all, pass filters=[].
OTHER OPTIONS
filtermode specifies the manner and timing in which filters
are applied to matching source elements. In the process of
creating the final HTML used in the mobile web page, the first
step is fetching and extracting 0 or more elements from the
source page. If filtermode is FILT_EACHELEM, the filters are
then applied to each element individually before
proceeding. The next stage is to collapse these elements into
a single container div element. If filtermode is
FILT_COLLAPSED, the filters are instead applied to this final
single element.
Note the significant complexity difference here: with N
filters and M elements matched from the source, the filter
application has complexity of no less than \Omega(N*M) with
filtermode FILT_EACHELEM, but complexity \Omega(M) for
FILT_COLLAPSED.
If innerhtml is False (the default), the selected element will
be extracted. If innerhtml is True, the actual content of
that element is extracted; the parent tag itself is dropped.
This only has an effect if there is exactly one matching
element, otherwise the innerhtml=False behavior is forced.
keep_if is, if supplied, a function taking an HtmlElement
argument, and returning True or False. The function is called
on every matching element; if False, the element is discarded
before proceeding. All this happens before any filters are
applied.
TODO: make FILT_COLLAPSED the default filtermode
@param selector : What part of the document to extract
@type selector : str, or list of str
@param filters : Absolute list of filters to use
@type filters : list of function
@param prefilters : Filters to prepend to default list
@type prefilters : list of function
@param postfilters : Filters to append to default list
@type postfilters : list of function
@param omitfilters : Filters to omit from default
@type omitfilters : set, or sequence that can be converted to a set
@param classvalue : Value of "class" attribute for containing div
@type classvalue : str or None (indicating use default)
@param idname : Value of "id" attribute for containing div
@type idname : str or None (indicating use default)
@param style : Value for "style" attribute for containing div
@type style : str
@param filtermode : Filter application mode
@type filtermode : int
@param usecopy : Whether to operate on a copy of the source element
@type usecopy : bool
@param tag : Name of containing tag
@type tag : str
@param keep_if : Selection predicate
@type keep_if : function: HtmlElement -> bool
@param innerhtml : If true, select the matching element's content only
@type innerhtml : bool
'''
if type(selector) in (list, tuple):
self.selectors = list(selector) # casting tuple to list
else:
self.selectors = [selector]
self.filters = _pick_filters(filters, prefilters, postfilters, omitfilters)
if classvalue is None:
classvalue = util.classvalue()
self.classvalue = classvalue
self.idname = idname
self.style = style
self.filtermode = filtermode
self.usecopy = usecopy
self.tag = tag
self.innerhtml = innerhtml
self.keep_if = keep_if
def test_classvalue(self):
self.assertSequenceEqual('mwu-elem', util.classvalue())
self.assertSequenceEqual('mwu-elem mwu-elem-alpha mwu-elem-beta', util.classvalue('alpha', 'beta'))
