NAME
Web::Query - Yet another scraping library like jQuery
SYNOPSIS
use Web::Query;
wq('http://www.w3.org/TR/html401/')
->find('div.head dt')
->each(sub {
my $i = shift;
printf("%d %s\n", $i+1, $_->text);
});
DESCRIPTION
Web::Query is a yet another scraping framework, have a jQuery like interface.
Yes, I know Ingy's pQuery. But it's just a alpha quality. It doesn't works. Web::Query built at top of the CPAN modules, HTML::TreeBuilder::XPath, LWP::UserAgent, and HTML::Selector::XPath.
So, this module uses HTML::Selector::XPath and only supports the CSS 3 selector supported by that module. Web::Query doesn't support jQuery's extended queries(yet?). If a selector is passed as a scalar ref, it'll be taken as a straight XPath expression.
$wq( '<div><p>hello</p><p>there</p></div>' )->find( 'p' ); # css selector
$wq( '<div><p>hello</p><p>there</p></div>' )->find( \'/div/p' ); # xpath selector
THIS LIBRARY IS UNDER DEVELOPMENT. ANY API MAY CHANGE WITHOUT NOTICE.
FUNCTIONS
METHODS
CONSTRUCTORS
- my $q = Web::Query->new($stuff, \%options )
-
Create new instance of Web::Query. You can make the instance from URL(http, https, file scheme), HTML in string, URL in string, URI object, and instance of HTML::Element.
This method throw the exception on unknown $stuff.
This method returns undefined value on non-successful response with URL.
Currently, the only two valid options are indent, which will be used as the indentation string if the object is printed, and no_space_compacting, which will prevent the compaction of whitespace characters in text blocks.
- my $q = Web::Query->new_from_element($element: HTML::Element)
-
Create new instance of Web::Query from instance of HTML::Element.
my $q = Web::Query->new_from_html($html: Str)
-
Create new instance of Web::Query from HTML.
- my $q = Web::Query->new_from_url($url: Str)
-
Create new instance of Web::Query from URL.
If the response is not success(It means /^20[0-9]$/), this method returns undefined value.
You can get a last result of response, use the
$Web::Query::RESPONSE
.Here is a best practical code:
my $url = 'http://example.com/'; my $q = Web::Query->new_from_url($url) or die "Cannot get a resource from $url: " . Web::Query->last_response()->status_line;
- my $q = Web::Query->new_from_file($file_name: Str)
-
Create new instance of Web::Query from file name.
TRAVERSING
add
Add elements to the set of matched elements.
- add($html)
-
An HTML fragment to add to the set of matched elements.
- add(@elements)
-
One or more @elements to add to the set of matched elements.
- add($wq)
-
An existing Web::Query object to add to the set of matched elements.
- add($selector, $context)
-
$selector is a string representing a selector expression to find additional elements to add to the set of matched elements.
$context is the point in the document at which the selector should begin matching
contents
Get the immediate children of each element in the set of matched elements, including text and comment nodes.
each
Visit each nodes. $i
is a counter value, 0 origin. $elem
is iteration item. $_
is localized by $elem
.
$q->each(sub { my ($i, $elem) = @_; ... })
end
Back to the before context like jQuery.
filter
Reduce the elements to those that pass the function's test.
$q->filter(sub { my ($i, $elem) = @_; ... })
find
Get the descendants of each element in the current set of matched elements, filtered by a selector.
my $q2 = $q->find($selector); # $selector is a CSS3 selector.
NOTE If you want to match the element itself, use "filter".
INCOMPATIBLE CHANGE From v0.14 to v0.19 (inclusive) find() also matched the element itself, which is not jQuery compatible. You can achieve that result using filter()
, add()
and find()
:
my $wq = wq('<div class="foo"><p class="foo">bar</p></div>'); # needed because we don't have a global document like jQuery does
print $wq->filter('.foo')->add($wq->find('.foo'))->as_html; # <div class="foo"><p class="foo">bar</p></div><p class="foo">bar</p>
first
Return the first matching element.
This method constructs a new Web::Query object from the first matching element.
last
Return the last matching element.
This method constructs a new Web::Query object from the last matching element.
map
Creates a new array with the results of calling a provided function on every element.
$q->map(sub { my ($i, $elem) = @_; ... })
parent
Get the parent of each element in the current set of matched elements.
prev
Get the previous node of each element in the current set of matched elements.
my $prev = $q->prev;
next
Get the next node of each element in the current set of matched elements.
my $next = $q->next;
MANIPULATION
add_class
Adds the specified class(es) to each of the set of matched elements.
# add class 'foo' to <p> elements
wq('<div><p>foo</p><p>bar</p></div>')->find('p')->add_class('foo');
after
Insert content, specified by the parameter, after each element in the set of matched elements.
wq('<div><p>foo</p></div>')->find('p')
->after('<b>bar</b>')
->end
->as_html; # <div><p>foo</p><b>bar</b></div>
The content can be anything accepted by "new".
append
Insert content, specified by the parameter, to the end of each element in the set of matched elements.
wq('<div></div>')->append('<p>foo</p>')->as_html; # <div><p>foo</p></div>
The content can be anything accepted by "new".
as_html
Return the elements associated with the object as strings. If called in a scalar context, only return the string representation of the first element.
attr
Get/Set the attribute value in element.
my $attr = $q->attr($name);
$q->attr($name, $val);
tagname
Get/Set the tag name of elements.
my $name = $q->tagname;
$q->tagname($new_name);
before
Insert content, specified by the parameter, before each element in the set of matched elements.
wq('<div><p>foo</p></div>')->find('p')
->before('<b>bar</b>')
->end
->as_html; # <div><b>bar</b><p>foo</p></div>
The content can be anything accepted by "new".
clone
Create a deep copy of the set of matched elements.
detach
Remove the set of matched elements from the DOM.
has_class
Determine whether any of the matched elements are assigned the given class.
html
Get/Set the innerHTML.
my @html = $q->html();
my $html = $q->html(); # 1st matching element only
$q->html('<p>foo</p>');
insert_before
Insert every element in the set of matched elements before the target.
insert_after
Insert every element in the set of matched elements after the target.
prepend
Insert content, specified by the parameter, to the beginning of each element in the set of matched elements.
remove
Delete the elements associated with the object from the DOM.
# remove all <blink> tags from the document
$q->find('blink')->remove;
remove_class
Remove a single class, multiple classes, or all classes from each element in the set of matched elements.
replace_with
Replace the elements of the object with the provided replacement. The replacement can be a string, a Web::Query
object or an anonymous function. The anonymous function is passed the index of the current node and the node itself (with is also localized as $_
).
my $q = wq( '<p><b>Abra</b><i>cada</i><u>bra</u></p>' );
$q->find('b')->replace_with('<a>Ocus</a>);
# <p><a>Ocus</a><i>cada</i><u>bra</u></p>
$q->find('u')->replace_with($q->find('b'));
# <p><i>cada</i><b>Abra</b></p>
$q->find('i')->replace_with(sub{
my $name = $_->text;
return "<$name></$name>";
});
# <p><b>Abra</b><cada></cada><u>bra</u></p>
size
Return the number of elements in the Web::Query object.
wq('<div><p>foo</p><p>bar</p></div>')->find('p')->size; # 2
text
Get/Set the text.
my @text = $q->text();
my $text = $q->text(); # 1st matching element only
$q->text('text');
If called in a scalar context, only return the string representation of the first element
OTHERS
HOW DO I CUSTOMIZE USER AGENT?
You can specify your own instance of LWP::UserAgent.
$Web::Query::UserAgent = LWP::UserAgent->new( agent => 'Mozilla/5.0' );
INCOMPATIBLE CHANGES
AUTHOR
Tokuhiro Matsuno <tokuhirom AAJKLFJEF@ GMAIL COM>
SEE ALSO
LICENSE
Copyright (C) Tokuhiro Matsuno
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.