1XML::SAX(3) User Contributed Perl Documentation XML::SAX(3)
2
3
4
6 XML::SAX - Simple API for XML
7
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
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
29 The factory class is XML::SAX::ParserFactory. Please see the
30 documentation 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
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
50 providing a number of methods automagically for you. See XML::SAX::Base
51 for 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
63 WriteMakefile(
64 ...
65 PREREQ_PM => { 'XML::SAX' => 0 },
66 ...
67 );
68
69 Alternatively you may wish to check for it in other ways that will
70 cause more than just a warning.
71
72 • Add the following code snippet to your Makefile.PL:
73
74 sub MY::install {
75 package MY;
76 my $script = shift->SUPER::install(@_);
77 if (ExtUtils::MakeMaker::prompt(
78 "Do you want to modify ParserDetails.ini?", 'Y')
79 =~ /^y/i) {
80 $script =~ s/install :: (.*)$/install :: $1 install_sax_driver/m;
81 $script .= <<"INSTALL";
82
83 install_sax_driver :
84 \t\@\$(PERL) -MXML::SAX -e "XML::SAX->add_parser(q(\$(NAME)))->save_parsers()"
85
86 INSTALL
87 }
88 return $script;
89 }
90
91 Note that you should check the output of this - \$(NAME) will use
92 the name of your distribution, which may not be exactly what you
93 want. For example XML::LibXML has a driver called
94 XML::LibXML::SAX::Generator, which is used in place of \$(NAME) in
95 the above.
96
97 • Add an XML::SAX test:
98
99 A test file should be added to your t/ directory containing
100 something like the following:
101
102 use Test;
103 BEGIN { plan tests => 3 }
104 use XML::SAX;
105 use XML::SAX::PurePerl::DebugHandler;
106 XML::SAX->add_parser(q(XML::SAX::MyDriver));
107 local $XML::SAX::ParserPackage = 'XML::SAX::MyDriver';
108 eval {
109 my $handler = XML::SAX::PurePerl::DebugHandler->new();
110 ok($handler);
111 my $parser = XML::SAX::ParserFactory->parser(Handler => $handler);
112 ok($parser);
113 ok($parser->isa('XML::SAX::MyDriver');
114 $parser->parse_string("<tag/>");
115 ok($handler->{seen}{start_element});
116 };
117
119 By default, XML::SAX exports nothing into the caller's namespace.
120 However you can request the symbols "Namespaces" and "Validation" which
121 are the URIs for those features, allowing an easier way to request
122 those features via ParserFactory:
123
124 use XML::SAX qw(Namespaces Validation);
125 my $factory = XML::SAX::ParserFactory->new();
126 $factory->require_feature(Namespaces);
127 $factory->require_feature(Validation);
128 my $parser = $factory->parser();
129
131 Current maintainer: Grant McLean, grantm@cpan.org
132
133 Originally written by:
134
135 Matt Sergeant, matt@sergeant.org
136
137 Kip Hampton, khampton@totalcinema.com
138
139 Robin Berjon, robin@knowscape.com
140
142 This is free software, you may use it and distribute it under the same
143 terms as Perl itself.
144
146 XML::SAX::Base for writing SAX Filters and Parsers
147
148 XML::SAX::PurePerl for an XML parser written in 100% pure perl.
149
150 XML::SAX::Exception for details on exception handling
151
152
153
154perl v5.34.0 2021-07-23 XML::SAX(3)