SAX(3) User Contributed Perl Documentation SAX(3)
NAME
XML::SAX - Simple API for XML
SYNOPSIS
use XML::SAX;
# get a list of known parsers
my $parsers = XML::SAX->parsers();
# add/update a parser
XML::SAX->add_parser(q(XML::SAX::PurePerl));
# remove parser
XML::SAX->remove_parser(q(XML::SAX::Foodelberry));
# save parsers
XML::SAX->save_parsers();
DESCRIPTION
XML::SAX is a SAX parser access API for Perl. It includes classes and
APIs required for implementing SAX drivers, along with a factory class
for returning any SAX parser installed on the user's system.
USING A SAX2 PARSER
The factory class is XML::SAX::ParserFactory. Please see the
documentation of that module for how to instantiate a SAX parser:
XML::SAX::ParserFactory. However if you don't want to load up another
manual page, here's a short synopsis:
use XML::SAX::ParserFactory;
use XML::SAX::XYZHandler;
my $handler = XML::SAX::XYZHandler->new();
my $p = XML::SAX::ParserFactory->parser(Handler => $handler);
$p->parse_uri("foo.xml");
# or $p->parse_string("<foo/>") or $p->parse_file($fh);
This will automatically load a SAX2 parser (defaulting to
XML::SAX::PurePerl if no others are found) and return it to you.
In order to learn how to use SAX to parse XML, you will need to read
XML::SAX::Intro and for reference, XML::SAX::Specification.
WRITING A SAX2 PARSER
The first thing to remember in writing a SAX2 parser is to subclass
XML::SAX::Base. This will make your life infinitely easier, by
providing a number of methods automagically for you. See XML::SAX::Base
for more details.
When writing a SAX2 parser that is compatible with XML::SAX, you need
to inform XML::SAX of the presence of that driver when you install it.
In order to do that, XML::SAX contains methods for saving the fact that
the parser exists on your system to a "INI" file, which is then loaded
to determine which parsers are installed.
The best way to do this is to follow these rules:
o Add XML::SAX as a prerequisite in Makefile.PL:
WriteMakefile(
...
PREREQ_PM => { 'XML::SAX' => 0 },
...
);
Alternatively you may wish to check for it in other ways that will
cause more than just a warning.
o Add the following code snippet to your Makefile.PL:
sub MY::install {
package MY;
my $script = shift->SUPER::install(@_);
if (ExtUtils::MakeMaker::prompt(
"Do you want to modify ParserDetails.ini?", 'Y')
=~ /^y/i) {
$script =~ s/install :: (.*)$/install :: $1 install_sax_driver/m;
$script .= <<"INSTALL";
install_sax_driver :
\t\@\$(PERL) -MXML::SAX -e "XML::SAX->add_parser(q(\$(NAME)))->save_parsers()"
INSTALL
}
return $script;
}
Note that you should check the output of this - \$(NAME) will use
the name of your distribution, which may not be exactly what you
want. For example XML::LibXML has a driver called
XML::LibXML::SAX::Generator, which is used in place of \$(NAME) in
the above.
o Add an XML::SAX test:
A test file should be added to your t/ directory containing
something like the following:
use Test;
BEGIN { plan tests => 3 }
use XML::SAX;
use XML::SAX::PurePerl::DebugHandler;
XML::SAX->add_parser(q(XML::SAX::MyDriver));
local $XML::SAX::ParserPackage = 'XML::SAX::MyDriver';
eval {
my $handler = XML::SAX::PurePerl::DebugHandler->new();
ok($handler);
my $parser = XML::SAX::ParserFactory->parser(Handler => $handler);
ok($parser);
ok($parser->isa('XML::SAX::MyDriver');
$parser->parse_string("<tag/>");
ok($handler->{seen}{start_element});
};
EXPORTS
By default, XML::SAX exports nothing into the caller's namespace.
However you can request the symbols "Namespaces" and "Validation" which
are the URIs for those features, allowing an easier way to request
those features via ParserFactory:
use XML::SAX qw(Namespaces Validation);
my $factory = XML::SAX::ParserFactory->new();
$factory->require_feature(Namespaces);
$factory->require_feature(Validation);
my $parser = $factory->parser();
AUTHOR
Current maintainer: Grant McLean, grantm AT cpan.org
Originally written by:
Matt Sergeant, matt AT sergeant.org
Kip Hampton, khampton AT totalcinema.com
Robin Berjon, robin AT knowscape.com
LICENSE
This is free software, you may use it and distribute it under the same
terms as Perl itself.
SEE ALSO
XML::SAX::Base for writing SAX Filters and Parsers
XML::SAX::PurePerl for an XML parser written in 100% pure perl.
XML::SAX::Exception for details on exception handling
perl v5.26.3 2018-02-15 SAX(3)