XML::SAX(3pm)

1SAX(3)                User Contributed Perl Documentation               SAX(3)
2
3
4

NAME

6       XML::SAX - Simple API for XML
7

SYNOPSIS

9         use XML::SAX;
10
11         # get a list of known parsers
12         my $parsers = XML::SAX->parsers();
13
14         # add/update a parser
15         XML::SAX->add_parser(q(XML::SAX::PurePerl));
16
17         # remove parser
18         XML::SAX->remove_parser(q(XML::SAX::Foodelberry));
19
20         # save parsers
21         XML::SAX->save_parsers();
22

DESCRIPTION

24       XML::SAX is a SAX parser access API for Perl. It includes classes and
25       APIs required for implementing SAX drivers, along with a factory class
26       for returning any SAX parser installed on the user's system.
27

USING A SAX2 PARSER

29       The factory class is XML::SAX::ParserFactory. Please see the documenta‐
30       tion of that module for how to instantiate a SAX parser:
31       XML::SAX::ParserFactory. However if you don't want to load up another
32       manual page, here's a short synopsis:
33
34         use XML::SAX::ParserFactory;
35         use XML::SAX::XYZHandler;
36         my $handler = XML::SAX::XYZHandler->new();
37         my $p = XML::SAX::ParserFactory->parser(Handler => $handler);
38         $p->parse_uri("foo.xml");
39         # or $p->parse_string("<foo/>") or $p->parse_file($fh);
40
41       This will automatically load a SAX2 parser (defaulting to
42       XML::SAX::PurePerl if no others are found) and return it to you.
43
44       In order to learn how to use SAX to parse XML, you will need to read
45       XML::SAX::Intro and for reference, XML::SAX::Specification.
46

WRITING A SAX2 PARSER

48       The first thing to remember in writing a SAX2 parser is to subclass
49       XML::SAX::Base. This will make your life infinitely easier, by provid‐
50       ing a number of methods automagically for you. See XML::SAX::Base for
51       more details.
52
53       When writing a SAX2 parser that is compatible with XML::SAX, you need
54       to inform XML::SAX of the presence of that driver when you install it.
55       In order to do that, XML::SAX contains methods for saving the fact that
56       the parser exists on your system to a "INI" file, which is then loaded
57       to determine which parsers are installed.
58
59       The best way to do this is to follow these rules:
60
61       * Add XML::SAX as a prerequisite in Makefile.PL:
62             WriteMakefile(
63                 ...
64                 PREREQ_PM => { 'XML::SAX' => 0 },
65                 ...
66             );
67
68           Alternatively you may wish to check for it in other ways that will
69           cause more than just a warning.
70
71       * Add the following code snippet to your Makefile.PL:
72             sub MY::install {
73               package MY;
74               my $script = shift->SUPER::install(@_);
75               if (ExtUtils::MakeMaker::prompt(
76                 "Do you want to modify ParserDetails.ini?", 'Y')
77                 =~ /^y/i) {
78                 $script =~ s/install :: (.*)$/install :: $1 install_sax_driver/m;
79                 $script .= <<"INSTALL";
80
81             install_sax_driver :
82             \t\@\$(PERL) -MXML::SAX -e "XML::SAX->add_parser(q(\$(NAME)))->save_parsers()"
83
84             INSTALL
85               }
86               return $script;
87             }
88
89           Note that you should check the output of this - \$(NAME) will use
90           the name of your distribution, which may not be exactly what you
91           want. For example XML::LibXML has a driver called
92           XML::LibXML::SAX::Generator, which is used in place of \$(NAME) in
93           the above.
94
95       * Add an XML::SAX test:
96           A test file should be added to your t/ directory containing some‐
97           thing like the following:
98
99             use Test;
100             BEGIN { plan tests => 3 }
101             use XML::SAX;
102             use XML::SAX::PurePerl::DebugHandler;
103             XML::SAX->add_parser(q(XML::SAX::MyDriver));
104             local $XML::SAX::ParserPackage = 'XML::SAX::MyDriver';
105             eval {
106               my $handler = XML::SAX::PurePerl::DebugHandler->new();
107               ok($handler);
108               my $parser = XML::SAX::ParserFactory->parser(Handler => $handler);
109               ok($parser);
110               ok($parser->isa('XML::SAX::MyDriver');
111               $parser->parse_string("<tag/>");
112               ok($handler->{seen}{start_element});
113             };
114

EXPORTS

116       By default, XML::SAX exports nothing into the caller's namespace. How‐
117       ever you can request the symbols "Namespaces" and "Validation" which
118       are the URIs for those features, allowing an easier way to request
119       those features via ParserFactory:
120
121         use XML::SAX qw(Namespaces Validation);
122         my $factory = XML::SAX::ParserFactory->new();
123         $factory->require_feature(Namespaces);
124         $factory->require_feature(Validation);
125         my $parser = $factory->parser();
126

AUTHOR

128       Current maintainer: Grant McLean, grantm@cpan.org
129
130       Originally written by:
131
132       Matt Sergeant, matt@sergeant.org
133
134       Kip Hampton, khampton@totalcinema.com
135
136       Robin Berjon, robin@knowscape.com
137

LICENSE

139       This is free software, you may use it and distribute it under the same
140       terms as Perl itself.
141