Provided by: libxml-hash-xs-perl_0.56-1build5_amd64
NAME
XML::Hash::XS - Simple and fast hash to XML and XML to hash conversion written in C
SYNOPSIS
use XML::Hash::XS; my $xmlstr = hash2xml \%hash; hash2xml \%hash, output => $fh; my $hash = xml2hash $xmlstr; my $hash = xml2hash \$xmlstr; my $hash = xml2hash 'test.xml', encoding => 'cp1251'; my $hash = xml2hash $fh; my $hash = xml2hash *STDIN; Or OOP way: use XML::Hash::XS qw(); my $conv = XML::Hash::XS->new(utf8 => 0, encoding => 'utf-8') my $xmlstr = $conv->hash2xml(\%hash, utf8 => 1); my $hash = $conv->xml2hash($xmlstr, encoding => 'cp1251');
DESCRIPTION
This module implements simple hash to XML and XML to hash conversion written in C. During conversion uses minimum of memory, XML or hash is written directly without building DOM. Some features are optional and are available with appropriate libraries: • XML::LibXML library is required in order to build DOM • ICU or iconv library is required in order to perform charset conversions
FUNCTIONS
hash2xml $hash, [ %options ] $hash is reference to hash hash2xml { node1 => 'value1', node2 => [ 'value21', { node22 => 'value22' } ], node3 => \'value3', node4 => sub { return 'value4' }, node5 => sub { return { node51 => 'value51' } }, }, canonical => 1, indent => 2, ; will convert to: <?xml version="1.0" encoding="utf-8"?> <root> <node1>value1</node1> <node2>value21</node2> <node2> <node22>value22</node22> </node2> <node3>value3</node3> <node4>value4</node4> <node5> <node51>value51</node51> </node5> </root> and (use_attr=1): hash2xml { node1 => 'value1', node2 => [ 'value21', { node22 => 'value22' } ], node3 => \'value3', node4 => sub { return 'value4' }, node5 => sub { return { node51 => 'value51' } }, }, use_attr => 1, canonical => 1, indent => 2, ; will convert to: <?xml version="1.0" encoding="utf-8"?> <root node1="value1" node3="value3" node4="value4"> <node2>value21</node2> <node2 node22="value22"/> <node5 node51="value51"/> </root> xml2hash $xml, [ %options ] $xml may be string, reference to string, file handle or tied file handle: xml2hash '<root>text</root>'; # output: 'text' xml2hash '<root a="1" b="2">text</root>'; # output: { a => '1', b => '2', content => 'text' } open(my $fh, '<', 'test.xml'); xml2hash $fh; xml2hash *STDIN;
OPTIONS
doc [ => 0 ] # hash2xml if doc is '1', then returned value is XML::LibXML::Document. root [ = 'root' ] # hash2xml Root node name. version [ = '1.0' ] # hash2xml XML document version encoding [ = 'utf-8' ] # hash2xml+xml2hash XML input/output encoding indent [ = 0 ] # hash2xml if indent great than "0", XML output should be indented according to its hierarchic structure. This value determines the number of spaces. if indent is "0", XML output will all be on one line. output [ = undef ] # hash2xml XML output method if output is undefined, XML document dumped into string. if output is FH, XML document writes directly to a filehandle or a stream. canonical [ = 0 ] # hash2xml if canonical is "1", converter will be write hashes sorted by key. if canonical is "0", order of the element will be pseudo-randomly. use_attr [ = 0 ] # hash2xml if use_attr is "1", converter will be use the attributes. if use_attr is "0", converter will be use tags only. content [ = undef ] # hash2xml+xml2hash if defined that the key name for the text content(used only if use_attr=1). force_array => [ = undef ] # xml2hash This option is similar to "ForceArray" from XML::Simple module: <https://metacpan.org/pod/XML::Simple#ForceArray-=%3E-1-%23-in-important>. force_content => [ = 0 ] # xml2hash This option is similar to "ForceContent" from XML::Simple module: <https://metacpan.org/pod/XML::Simple#ForceContent-=%3E-1-%23-in-seldom-used>. merge_text [ = 0 ] # xml2hash Setting this option to "1" will cause merge adjacent text nodes. xml_decl [ = 1 ] # hash2xml if xml_decl is "1", output will start with the XML declaration '<?xml version="1.0" encoding="utf-8"?>'. if xml_decl is "0", XML declaration will not be output. trim [ = 0 ] # hash2xml+xml2hash Trim leading and trailing whitespace from text nodes. suppress_empty => [ = 0 ] # xml2hash This option is similar to "SuppressEmpty" from XMl::Simple module: <https://metacpan.org/pod/XML::Simple#SuppressEmpty-=%3E-1-%7C-''-%7C-undef-%23-in+out-handy>. utf8 [ = 1 ] # hash2xml+xml2hash Turn on utf8 flag for strings if enabled. max_depth [ = 1024 ] # xml2hash Maximum recursion depth. buf_size [ = 4096 ] # hash2xml+xml2hash Buffer size for reading end encoding data. keep_root [ = 0 ] # xml2hash Keep root element. filter [ = undef ] # xml2hash Filter nodes matched by pattern and return reference to array of nodes. Sample: my $xml = <<'XML'; <root> <item1>111</item1> <item2>222</item2> <item3>333</item3> </root> XML my $nodes = xml2hash($xml, filter => '/root/item1'); # $nodes = [ 111 ] my $nodes = xml2hash($xml, filter => ['/root/item1', '/root/item2']); # $nodes = [ 111, 222 ] my $nodes = xml2hash($xml, filter => qr[/root/item\d$]); # $nodes = [ 111, 222, 333 ] It may be used to parse large XML because does not require a lot of memory. cb [ = undef ] # xml2hash This option is used in conjunction with "filter" option and defines callback that will called for each matched node. Sample: xml2hash($xml, filter => qr[/root/item\d$], cb => sub { print $_[0], "\n"; }); # 111 # 222 # 333 method [ = 'NATIVE' ] # hash2xml experimental support the conversion methods other libraries if method is 'LX' then conversion result is the same as using XML::Hash::LX library Note: for 'LX' method following additional options are available: attr cdata text comm
OBJECT SERIALISATION(hash2xml)
1. When object has a "toString" method In this case, the <toString> method of object is invoked in scalar context. It must return a single scalar that can be directly encoded into XML. Example: use XML::LibXML; local $XML::LibXML::skipXMLDeclaration = 1; my $doc = XML::LibXML->new->parse_string('<foo bar="1"/>'); print hash2xml({ doc => $doc }, indent => 2, xml_decl => 0); => <root> <doc><foo bar="1"/></doc> </root> 2. When object has overloaded stringification In this case, the stringification method of object is invoked and result is directly encoded into XML. Example: package Test { use overload '""' => sub { shift->stringify }, fallback => 1; sub new { my ($class, $str) = @_; bless { str => $str }, $class; } sub stringify { shift->{str} } } my $obj = Test->new('test string'); print hash2xml({ obj => $obj }, indent => 2, xml_decl => 0); => <root> <obj>test string</obj> </root> 3. When object has a "iternext" method ("NATIVE" method only) In this case, the <iternext> method method will invoke a few times until the return value is not undefined. Example: my $count = 0; my $o = bless {}, 'Iterator'; *Iterator::iternext = sub { $count++ < 3 ? { count => $count } : undef }; print hash2xml({ item => $o }, use_attr => 1, indent => 2, xml_decl => 0); => <root> <item count="1"/> <item count="2"/> <item count="3"/> </root> This can be used to generate a large XML using minimum memory, example with DBI: my $sth = $dbh->prepare('SELECT * FROM foo WHERE bar=?'); $sth->execute(...); my $o = bless {}, 'Iterator'; *Iterator::iternext = sub { $sth->fetchrow_hashref() }; open(my $fh, '>', 'data.xml'); hash2xml({ row => $o }, use_attr => 1, indent => 2, xml_decl => 0, output => $fh); => <root> <row bar="..." ... /> <row bar="..." ... /> ... </root>
BENCHMARK
Performance benchmark in comparison with some popular modules(hash2xml): Rate XML::Hash XML::Hash::LX XML::Simple XML::Hash::XS XML::Hash 65.0/s -- -6% -37% -99% XML::Hash::LX 68.8/s 6% -- -33% -99% XML::Simple 103/s 58% 49% -- -98% XML::Hash::XS 4879/s 7404% 6988% 4658% -- Benchmark was done on <http://search.cpan.org/uploads.rdf>
AUTHOR
Yuriy Ustushenko, <yoreek@yahoo.com>
COPYRIGHT AND LICENSE
Copyright (C) 2012-2021 Yuriy Ustushenko This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.