package Web::Query;
our $AUTHORITY = 'cpan:TOKUHIROM';
# ABSTRACT: Yet another scraping library like jQuery
$Web::Query::VERSION = '1.01';
use strict;
use warnings;
use 5.008001;
use parent qw/Exporter/;
use HTML::TreeBuilder::XPath;
use LWP::UserAgent;
use HTML::Selector::XPath 0.20 qw/selector_to_xpath/;
use Scalar::Util qw/blessed refaddr/;
use HTML::Entities qw/encode_entities/;
use List::Util 1.44 qw/ reduce uniq /;
use Scalar::Util qw/ refaddr /;
our @EXPORT = qw/wq/;
our $RESPONSE;
sub wq { Web::Query->new(@_) }
our $UserAgent;
sub __ua { $UserAgent ||= LWP::UserAgent->new }
sub _build_tree {
my( $self, $options ) = @_;
my $no_space_compacting = ref $self ? $self->{no_space_compacting}
: ref $options eq 'HASH' ? $options->{no_space_compacting} : 0;
my $tree = HTML::TreeBuilder::XPath->new(
no_space_compacting => $no_space_compacting
);
$tree->ignore_unknown(0);
$tree->store_comments(1);
$tree;
}
sub new {
my ($class, $stuff, $options) = @_;
my $self = $class->_resolve_new($stuff,$options)
or return undef;
$self->{indent} = $options->{indent} if $options->{indent};
$self->{no_space_compacting} = $options->{no_space_compacting};
return $self;
}
sub _resolve_new {
my( $class, $stuff, $options) = @_;
return $class->new_from_element([],undef,$options) unless defined $stuff;
if (blessed $stuff) {
return $class->new_from_element([$stuff],undef,$options)
if $stuff->isa('HTML::Element');
return $class->new_from_url($stuff->as_string,$options)
if $stuff->isa('URI');
return $class->new_from_element($stuff->{trees}, undef, $options)
if $stuff->isa($class);
die "Unknown source type: $stuff";
}
return $class->new_from_element($stuff,undef,$options) if ref $stuff eq 'ARRAY';
return $class->new_from_url($stuff,$options) if $stuff =~ m{^(?:https?|file)://};
return $class->new_from_html($stuff,$options) if $stuff =~ /<.*?>/;
return $class->new_from_file($stuff,$options) if $stuff !~ /\n/ && -f $stuff;
die "Unknown source type: $stuff";
}
sub new_from_url {
my ($class, $url,$options) = @_;
$RESPONSE = __ua()->get($url);
no warnings 'uninitialized';
unless( $RESPONSE->is_success ) {
die "failed to retrieve '$url', " . $RESPONSE->code. " "
. $RESPONSE->message."\n";
};
return $class->new_from_html($RESPONSE->decoded_content,$options);
}
sub new_from_file {
my ($class, $fname, $options) = @_;
my $tree = $class->_build_tree($options);
$tree->parse_file($fname);
my $self = $class->new_from_element([$tree->disembowel],undef,$options);
$self->{need_delete}++;
return $self;
}
sub new_from_html {
my ($class, $html,$options) = @_;
my $tree = $class->_build_tree($options);
$tree->parse_content($html);
my $self = $class->new_from_element([
map {
ref $_ ? $_ : bless { _content => $_ }, 'HTML::TreeBuilder::XPath::TextNode'
} $tree->disembowel
],undef,$options);
$self->{need_delete}++;
return $self;
}
sub new_from_element {
my $self_or_class = shift;
my $trees = ref $_[0] eq 'ARRAY' ? $_[0] : [$_[0]];
return bless { trees => [ @$trees ], before => $_[1] },
ref $self_or_class || $self_or_class;
}
sub end {
my $self = shift;
return $self->{before};
}
sub size {
my $self = shift;
return scalar(@{$self->{trees}});
}
sub parent {
my $self = shift;
my @new = map { $_->parent } @{$self->{trees}};
return (ref $self || $self)->new_from_element(\@new, $self);
}
sub first {
my $self = shift;
return $self->eq(0);
}
sub last {
my $self = shift;
return $self->eq(-1);
}
sub get {
my ($self, $index) = @_;
return $self->{trees}[$index];
}
sub eq {
my ($self, $index) = @_;
return (ref $self || $self)->new_from_element([$self->{trees}[$index] || ()], $self);
}
sub find {
my ($self, $selector) = @_;
my $xpath = ref $selector ? $$selector : selector_to_xpath($selector, root => './');
my @new = map { eval{ $_->findnodes($xpath) } } @{$self->{trees}};
return (ref $self || $self)->new_from_element(\@new, $self);
}
sub contents {
my ($self, $selector) = @_;
my @new = map { $_->content_list } @{$self->{trees}};
if ($selector) {
my $xpath = ref $selector ? $$selector : selector_to_xpath($selector);
@new = grep { $_->matches($xpath) } @new;
}
return (ref $self || $self)->new_from_element(\@new, $self);
}
sub as_html {
my $self = shift;
my %args = @_;
my @html = map {
ref $_ ? ( $_->isa('HTML::TreeBuilder::XPath::TextNode') || $_->isa('HTML::TreeBuilder::XPath::CommentNode' ) )
? $_->getValue
: $_->as_HTML( q{&<>'"}, $self->{indent}, {} )
: $_
} @{$self->{trees}};
return join $args{join}, @html if defined $args{join};
return wantarray ? @html : $html[0];
}
sub html {
my $self = shift;
if (@_) {
map {
$_->delete_content;
my $tree = $self->_build_tree;
$tree->parse_content($_[0]);
$_->push_content($tree->disembowel);
} @{$self->{trees}};
return $self;
}
my @html;
for my $t ( @{$self->{trees}} ) {
push @html, join '', map {
ref $_ ? $_->as_HTML( q{&<>'"}, $self->{indent}, {})
: encode_entities($_)
} eval { $t->content_list };
}
return wantarray ? @html : $html[0];
}
sub text {
my $self = shift;
if (@_) {
map { $_->delete_content; $_->push_content($_[0]) } @{$self->{trees}};
return $self;
}
my @html = map {
ref $_ ? $_->as_text : $_
} @{$self->{trees}};
return wantarray ? @html : $html[0];
}
sub attr {
my $self = shift;
if ( @_ == 1 ) { # getter
return wantarray
? map { $_->attr(@_) } @{$self->{trees}}
: eval { $self->{trees}[0]->attr(@_) }
;
}
while( my( $attr, $value ) = splice @_, 0, 2 ) {
my $code = ref $value eq 'CODE' ? $value : undef;
for my $t ( @{$self->{trees}} ) {
if ( $code ) {
no warnings 'uninitialized';
my $orig = $_ = $t->attr($attr);
$code->();
next if $orig eq $_;
$value = $_;
}
$t->attr($attr => $value);
}
}
return $self;
}
sub id {
my $self = shift;
if ( @_ ) { # setter
my $new_id = shift;
return $self if $self->size == 0;
return $self->each(sub{
$_->attr( id => $new_id->(@_) )
}) if ref $new_id eq 'CODE';
if ( $self->size == 1 ) {
$self->attr( id => $new_id );
}
else {
return $self->first->attr( id => $new_id );
}
}
else { # getter
# the eval is there in case there is no tree
return wantarray
? map { $_->attr('id') } @{$self->{trees}}
: eval { $self->{trees}[0]->attr('id') }
;
}
}
sub name {
my $self = shift;
$self->attr( 'name', @_ );
}
sub data {
my $self = shift;
my $name = shift;
$self->attr( join( '-', 'data', $name ), @_ );
}
sub tagname {
my $self = shift;
my @retval = map { $_ eq '~comment' ? '#comment' : $_ }
map { ref $_ eq 'HTML::TreeBuilder::XPath::TextNode' ? '#text'
: ref $_ eq 'HTML::TreeBuilder::XPath::CommentNode' ? '#comment'
: ref $_ ? $_->tag(@_)
: '#text'
;
} @{$self->{trees}};
return wantarray ? @retval : $retval[0];
}
sub each {
my ($self, $code) = @_;
my $i = 0;
# make a copy such that if we modify the list via 'delete',
# it won't change from under our feet (see t/each-and-delete.t
# for a case where it can)
my @trees = @{ $self->{trees} };
for my $tree ( @trees ) {
local $_ = (ref $self || $self)->new_from_element([$tree], $self);
$code->($i++, $_);
}
return $self;
}
sub map {
my ($self, $code) = @_;
my $i = 0;
return +[map {
my $tree = $_;
local $_ = (ref $self || $self)->new($tree);
$code->($i++, $_);
} @{$self->{trees}}];
}
sub filter {
my $self = shift;
my @new;
if (ref($_[0]) eq 'CODE') {
my $code = $_[0];
my $i = 0;
@new = grep {
my $tree = $_;
local $_ = (ref $self || $self)->new_from_element($tree);
$code->($i++, $_);
} @{$self->{trees}};
}
else {
my $xpath = ref $_[0] ? ${$_[0]} : selector_to_xpath($_[0]);
@new = grep { eval { $_->matches($xpath) } } @{$self->{trees}};
}
return (ref $self || $self)->new_from_element(\@new, $self);
}
sub _is_same_node {
refaddr($_[1]) == refaddr($_[2]);
}
sub remove {
my $self = shift;
my $before = $self->end;
while (defined $before) {
@{$before->{trees}} = grep {
my $el = $_;
not grep { $self->_is_same_node( $el, $_ ) } @{$self->{trees}};
} @{$before->{trees}};
$before = $before->end;
}
$_->delete for @{$self->{trees}};
@{$self->{trees}} = ();
$self;
}
sub replace_with {
my ( $self, $replacement ) = @_;
my $i = 0;
for my $node ( @{ $self->{trees} } ) {
my $rep = $replacement;
if ( ref $rep eq 'CODE' ) {
local $_ = (ref $self || $self)->new($node);
$rep = $rep->( $i++ => $_ );
}
$rep = (ref $self || $self)->new_from_html( $rep )
unless ref $rep;
my $r = $rep->{trees}->[0];
{ no warnings;
$r = $r->clone if ref $r;
}
$r->parent( $node->parent ) if ref $r and $node->parent;
$node->replace_with( $r );
}
$replacement->remove if ref $replacement eq (ref $self || $self);
return $self;
}
sub append {
my ($self, $stuff) = @_;
$stuff = (ref $self || $self)->new($stuff);
foreach my $t (@{$self->{trees}}) {
$t->push_content($_) for ref($t)->clone_list(@{$stuff->{trees}});
}
$self;
}
sub prepend {
my ($self, $stuff) = @_;
$stuff = (ref $self || $self)->new($stuff);
foreach my $t (@{$self->{trees}}) {
$t->unshift_content($_) for ref($t)->clone_list(@{$stuff->{trees}});
}
$self;
}
sub before {
my ($self, $stuff) = @_;
$stuff = (ref $self || $self)->new($stuff);
foreach my $t (@{$self->{trees}}) {
$t->preinsert(ref($t)->clone_list(@{$stuff->{trees}}));
}
$self;
}
sub after {
my ($self, $stuff) = @_;
$stuff = (ref $self || $self)->new($stuff);
foreach my $t (@{$self->{trees}}) {
$t->postinsert(ref($t)->clone_list(@{$stuff->{trees}}));
}
$self;
}
sub insert_before {
my ($self, $target) = @_;
foreach my $t (@{$target->{trees}}) {
$t->preinsert(ref($t)->clone_list(@{$self->{trees}}));
}
$self;
}
sub insert_after {
my ($self, $target) = @_;
foreach my $t (@{$target->{trees}}) {
$t->postinsert(ref($t)->clone_list(@{$self->{trees}}));
}
$self;
}
sub detach {
my ($self) = @_;
$_->detach for @{$self->{trees}};
$self;
}
sub add_class {
my ($self, $class) = @_;
for (my $i = 0; $i < @{$self->{trees}}; $i++) {
my $t = $self->{trees}->[$i];
my $current_class = $t->attr('class') || '';
my $classes = ref $class eq 'CODE' ? $class->($i, $current_class, $t) : $class;
my @classes = split /\s+/, $classes;
foreach (@classes) {
$current_class .= " $_" unless $current_class =~ /(?:^|\s)$_(?:\s|$)/;
}
$current_class =~ s/(?:^\s*|\s*$)//g;
$current_class =~ s/\s\s+/ /g;
$t->attr('class', $current_class);
}
$self;
}
sub remove_class {
my ($self, $class) = @_;
for (my $i = 0; $i < @{$self->{trees}}; $i++) {
my $t = $self->{trees}->[$i];
my $current_class = $t->attr('class');
next unless defined $current_class;
my $classes = ref $class eq 'CODE' ? $class->($i, $current_class, $t) : $class;
my @remove_classes = split /\s+/, $classes;
my @final = grep {
my $existing_class = $_;
not grep { $existing_class eq $_} @remove_classes;
} split /\s+/, $current_class;
$t->attr('class', join ' ', @final);
}
$self;
}
sub toggle_class {
my $self = shift;
my @classes = uniq @_;
$self->each(sub{
for my $class ( @classes ) {
my $method = $_->has_class($class) ? 'remove_class' : 'add_class';
$_->$method($class);
}
});
}
sub has_class {
my ($self, $class) = @_;
foreach my $t (@{$self->{trees}}) {
no warnings 'uninitialized';
return 1 if $t->attr('class') =~ /(?:^|\s)$class(?:\s|$)/;
}
return undef;
}
sub clone {
my ($self) = @_;
my @clones = map { $_->clone } @{$self->{trees}};
return (ref $self || $self)->new_from_element(\@clones);
}
sub add {
my ($self, @stuff) = @_;
my @nodes;
# add(selector, context)
if (@stuff == 2 && !ref $stuff[0] && $stuff[1]->isa('HTML::Element')) {
my $xpath = ref $stuff[0] ? ${$stuff[0]} : selector_to_xpath($stuff[0]);
push @nodes, $stuff[1]->findnodes( $xpath, root => './');
}
else {
# handle any combination of html string, element object and web::query object
push @nodes, map {
$self->{need_delete} = 1 if $_->{need_delete};
delete $_->{need_delete};
@{$_->{trees}};
} map { (ref $self || $self)->new($_) } @stuff;
}
my %ids = map { $self->_node_id($_) => 1 } @{ $self->{trees} };
$self->new_from_element( [
@{$self->{trees}}, grep { ! $ids{ $self->_node_id($_) } } @nodes
], $self );
}
sub _node_id {
my( undef, $node ) = @_;
refaddr $node;
}
sub prev {
my $self = shift;
my @new;
for my $tree (@{$self->{trees}}) {
push @new, $tree->getPreviousSibling;
}
return (ref $self || $self)->new_from_element(\@new, $self);
}
sub next {
my $self = shift;
my @new = grep { $_ } map { $_->getNextSibling } @{ $self->{trees} };
return (ref $self || $self)->new_from_element(\@new, $self);
}
sub match {
my( $self, $selector ) = @_;
my $xpath = ref $selector ? $$selector : selector_to_xpath($selector);
my $results = $self->map(sub{
my(undef,$e) = @_;
return 0 unless ref $e; # it's a string
return !!$e->get(0)->matches($xpath);
});
return wantarray ? @$results : $results->[0];
}
sub not {
my( $self, $selector ) = @_;
my $class = ref $self;
my $xpath = ref $selector ? $$selector : selector_to_xpath($selector);
$self->filter(sub { ! grep { $_->matches($xpath) } grep { ref $_ } $class->new($_)->{trees}[0] } );
}
sub and_back {
my $self = shift;
$self->add( $self->end );
}
sub next_until {
my( $self, $selector ) = @_;
my $class = ref $self;
my $collection = $class->new_from_element([],$self);
my $next = $self->next->not($selector);
while( $next->size ) {
$collection = $collection->add($next);
$next = $next->next->not( $selector );
}
# hide the loop from the outside world
$collection->{before} = $self;
return $collection;
}
sub split {
my( $self, $selector, %args ) = @_;
my @current;
my @list;
$self->contents->each(sub{
my(undef,$e)=@_;
if( $e->match($selector) ) {
push @list, [ @current ];
@current = ( $e );
}
else {
if ( $current[1] ) {
$current[1] = $current[1]->add($e);
}
else {
$current[1] = $e;
}
}
});
push @list, [ @current ];
if( $args{skip_leading} ) {
@list = grep { $_->[0] } @list;
}
unless ( $args{pairs} ) {
@list = map { reduce { $a->add($b) } grep { $_ } @$_ } @list;
}
return @list;
}
sub last_response {
return $RESPONSE;
}
sub DESTROY {
return unless $_[0]->{need_delete};
# avoid memory leaks
local $@;
eval { $_->delete } for @{$_[0]->{trees}};
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
Web::Query - Yet another scraping library like jQuery
=head1 VERSION
version 1.01
=head1 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);
});
=head1 DESCRIPTION
Web::Query is a yet another scraping framework, have a jQuery like interface.
Yes, I know Ingy's L<pQuery>. But it's just alpha quality. It doesn't work.
Web::Query built at top of the CPAN modules, L<HTML::TreeBuilder::XPath>, L<LWP::UserAgent>, and L<HTML::Selector::XPath>.
So, this module uses L<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
$wq( '<div><p>hello</p><p>there</p></div>' )->find( \'/div/p' ); # xpath selector
B<THIS LIBRARY IS UNDER DEVELOPMENT. ANY API MAY CHANGE WITHOUT NOTICE>.
=for stopwords prev
=head1 FUNCTIONS
=over 4
=item C<< wq($stuff) >>
This is a shortcut for C<< Web::Query->new($stuff) >>. This function is exported by default.
=back
=head1 METHODS
=head2 CONSTRUCTORS
=over 4
=item 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, L<URI> object, C<undef>, and either one
L<HTML::Element> object or an array ref of them.
# all valid creators
$q = Web::Query->new( 'http://techblog.babyl.ca' );
$q = Web::Query->new( '<p>foo</p>' );
$q = Web::Query->new( undef );
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 I<indent>, which will be used as
the indentation string if the object is printed, and I<no_space_compacting>,
which will prevent the compaction of whitespace characters in text blocks.
=item my $q = Web::Query->new_from_element($element: HTML::Element)
Create new instance of Web::Query from instance of L<HTML::Element>.
=item C<< my $q = Web::Query->new_from_html($html: Str) >>
Create new instance of Web::Query from HTML.
=item 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 C<< $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;
=item my $q = Web::Query->new_from_file($file_name: Str)
Create new instance of Web::Query from file name.
=back
=head2 TRAVERSING
=head3 add
Returns a new object augmented with the new element(s).
=over 4
=item add($html)
An HTML fragment to add to the set of matched elements.
=item add(@elements)
One or more @elements to add to the set of matched elements.
@elements that already are part of the set are not added a second time.
my $group = $wq->find('#foo'); # collection has 1 element
$group = $group->add( '#bar', $wq ); # 2 elements
$group->add( '#foo', $wq ); # still 2 elements
=item add($wq)
An existing Web::Query object to add to the set of matched elements.
=item 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
=back
=head3 contents
Get the immediate children of each element in the set of matched elements, including text and comment nodes.
=head3 each
Visit each nodes. C<< $i >> is a counter value, 0 origin. C<< $elem >> is iteration item.
C<< $_ >> is localized by C<< $elem >>.
$q->each(sub { my ($i, $elem) = @_; ... })
=head3 end
Back to the before context like jQuery.
=head3 filter
Reduce the elements to those that pass the function's test.
$q->filter(sub { my ($i, $elem) = @_; ... })
=head3 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.
B<NOTE> If you want to match the element itself, use L</filter>.
B<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 C<filter()>, C<add()> and C<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>
=head3 first
Return the first matching element.
This method constructs a new Web::Query object from the first matching element.
=head3 last
Return the last matching element.
This method constructs a new Web::Query object from the last matching element.
=head3 match($selector)
Returns a boolean indicating if the elements match the C<$selector>.
In scalar context returns only the boolean for the first element.
For the reverse of C<not()>, see C<filter()>.
=head3 not($selector)
Returns all the elements not matching the C<$selector>.
# $do_for_love will be every thing, except #that
my $do_for_love = $wq->find('thing')->not('#that');
=head3 and_back
Add the previous set of elements to the current one.
# get the h1 plus everything until the next h1
$wq->find('h1')->next_until('h1')->and_back;
=head3 map
Creates a new array with the results of calling a provided function on every element.
$q->map(sub { my ($i, $elem) = @_; ... })
=head3 parent
Get the parent of each element in the current set of matched elements.
=head3 prev
Get the previous node of each element in the current set of matched elements.
my $prev = $q->prev;
=head3 next
Get the next node of each element in the current set of matched elements.
my $next = $q->next;
=head3 next_until( $selector )
Get all subsequent siblings, up to (but not including) the next node matched C<$selector>.
=head2 MANIPULATION
=head3 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');
=head3 toggle_class( @classes )
Toggles the given class or classes on each of the element. I.e., if the element had the class, it'll be removed,
and if it hadn't, it'll be added.
Classes are toggled once, no matter how many times they appear in the argument list.
$q->toggle_class( 'foo', 'foo', 'bar' );
# equivalent to
$q->toggle_class('foo')->toggle_class('bar');
# and not
$q->toggle_class('foo')->toggle_class('foo')->toggle_class('bar');
=head3 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 L</new>.
=head3 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 L</new>.
=head3 as_html
Returns the string representations of either the first or all elements,
depending if called in list or scalar context.
If given an argument C<join>, the string representations of the elements
will be concatenated with the given string.
wq( '<div><p>foo</p><p>bar</p></div>' )
->find('p')
->as_html( join => '!' );
# <p>foo</p>!<p>bar</p>
=head3 C< attr >
Get/set attribute values.
In getter mode, it'll return either the values of the attribute
for all elements of the set, or only the first one depending of the calling context.
my @values = $q->attr('style'); # style of all elements
my $first_value = $q->attr('style'); # style of first element
In setter mode, it'll set attributes value for all elements, and return back
the original object for easy chaining.
$q->attr( 'alt' => 'a picture' )->find( ... );
# can pass more than 1 element too
$q->attr( alt => 'a picture', src => 'file:///...' );
The value passed for an attribute can be a code ref. In that case,
the code will be called with C<$_> set to the current attribute value.
If the code modifies C<$_>, the attribute will be updated with the new value.
$q->attr( alt => sub { $_ ||= 'A picture' } );
=head3 C< id >
Get/set the elements's id attribute.
In getter mode, it behaves just like C<attr()>.
In setter mode, it behaves like C<attr()>, but with the following exceptions.
If the attribute value is a scalar, it'll be only assigned to
the first element of the set (as ids are supposed to be unique), and the returned object will only contain
that first element.
my $first_element = $q->id('the_one');
It's possible to set the ids of all the elements by passing a sub to C<id()>. The sub is given the same arguments as for
C<each()>, and its return value is taken to be the new id of the elements.
$q->id( sub { my $i = shift; 'foo_' . $i } );
=head3 C< name >
Get/set the elements's 'name' attribute.
my $name = $q->name; # equivalent to $q->attr( 'name' );
$q->name( 'foo' ); # equivalent to $q->attr( name => 'foo' );
=head3 C< data >
Get/set the elements's 'data-*name*' attributes.
my $data = $q->data('foo'); # equivalent to $q->attr( 'data-foo' );
$q->data( 'foo' => 'bar' ); # equivalent to $q->attr( 'data-foo' => 'bar' );
=head3 tagname
Get/Set the tag name of elements.
my $name = $q->tagname;
$q->tagname($new_name);
=head3 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 L</new>.
=head3 clone
Create a deep copy of the set of matched elements.
=head3 detach
Remove the set of matched elements from the DOM.
=head3 has_class
Determine whether any of the matched elements are assigned the given class.
=head3 C< html >
Get/Set the innerHTML.
my @html = $q->html();
my $html = $q->html(); # 1st matching element only
$q->html('<p>foo</p>');
=head3 insert_before
Insert every element in the set of matched elements before the target.
=head3 insert_after
Insert every element in the set of matched elements after the target.
=head3 C< prepend >
Insert content, specified by the parameter, to the beginning of each element in the set of matched elements.
=head3 remove
Delete the elements associated with the object from the DOM.
# remove all <blink> tags from the document
$q->find('blink')->remove;
=head3 remove_class
Remove a single class, multiple classes, or all classes from each element in the set of matched elements.
=head3 replace_with
Replace the elements of the object with the provided replacement.
The replacement can be a string, a C<Web::Query> object or an
anonymous function. The anonymous function is passed the index of the current
node and the node itself (with is also localized as C<$_>).
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>
=head3 size
Return the number of elements in the Web::Query object.
wq('<div><p>foo</p><p>bar</p></div>')->find('p')->size; # 2
=head3 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
=head2 OTHERS
=over 4
=item Web::Query->last_response()
Returns last HTTP response status that generated by C<new_from_url()>.
=back
=head1 HOW DO I CUSTOMIZE USER AGENT?
You can specify your own instance of L<LWP::UserAgent>.
$Web::Query::UserAgent = LWP::UserAgent->new( agent => 'Mozilla/5.0' );
=head1 FAQ AND TROUBLESHOOTING
=head2 How to find XML processing instructions in a document?
It's possible with L<Web::Query::LibXML> and by using an xpath expression
with C<find()>:
# find <?xml-stylesheet ... ?>
$q->find(\"//processing-instruction('xml-stylesheet')");
However, note that the support for processing instructions
in L<HTML::TreeBuilder::LibXML::Node> is sketchy, so there
are methods like C<attr()> that won't work.
=head2 Can't get the content of script elements
The <script> tag is treated differently by L<HTML::TreeBuilder>, the
parser used by Web::Query. To retrieve the content, you can use either
the method C<html()> (with the caveat that the content will be escaped),
or use L<Web::Query::LibXML>, which parse the 'script' element differently.
my $node = "<script>var x = '<p>foo</p>';</script>";
say Web::Query::wq( $node )->text;
# nothing is printed!
say Web::Query::wq( $node )->html;
# var x = '<p>foo</p>';
say Web::Query::LibXML::wq( $node )->text;
# var x = '<p>foo</p>';
say Web::Query::LibXML::wq( $node )->html;
# var x = '<p>foo</p>';
=head1 INCOMPATIBLE CHANGES
=over 4
=item 0.10
new_from_url() is no longer throws exception on bad response from HTTP server.
=back
=head1 AUTHOR
Tokuhiro Matsuno E<lt>tokuhirom AAJKLFJEF@ GMAIL COME<gt>
=head1 SEE ALSO
=over
=item L<pQuery>
=item L<XML::LibXML::jQuery>
=back
=head1 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.
=head1 BUGS
Please report any bugs or feature requests on the bugtracker website
L<https://github.com/tokuhirom/Web-Query/issues>
When submitting a bug or request, please include a test-file or a
patch to an existing test-file that illustrates the bug or desired
feature.
=cut