Commit | Line | Data |
e58153d6 |
1 | package Text::Tradition::Parser::GraphML; |
b49c4318 |
2 | |
3 | use strict; |
4 | use warnings; |
e867486f |
5 | use Exporter 'import'; |
6 | use vars qw/ @EXPORT_OK $xpc /; |
7 | |
b49c4318 |
8 | use XML::LibXML; |
9 | use XML::LibXML::XPathContext; |
10 | |
1f7aa795 |
11 | @EXPORT_OK = qw/ graphml_parse /; |
e867486f |
12 | |
2ceca8c3 |
13 | =head1 NAME |
b49c4318 |
14 | |
2ceca8c3 |
15 | Text::Tradition::Parser::GraphML |
16 | |
17 | =head1 DESCRIPTION |
18 | |
19 | Parser module for Text::Tradition, given a GraphML file that describes |
ec3f9144 |
20 | a collation graph. Returns the information about the graph that has |
21 | been parsed out from the GraphML. This module is meant to be used |
22 | with a module (e.g. CollateX or Self) that interprets the specific |
23 | GraphML conventions of the source program. |
2ceca8c3 |
24 | |
25 | =head1 METHODS |
26 | |
e867486f |
27 | =head2 B<graphml_parse>( $init_opts ) |
2ceca8c3 |
28 | |
dfc37e38 |
29 | parse( $init_opts ); |
2ceca8c3 |
30 | |
dfc37e38 |
31 | Takes a set of Tradition initialization options, among which should be either |
32 | 'file' or 'string'; parses that file or string and returns a list of nodes, edges, |
ec3f9144 |
33 | and their associated data. |
2ceca8c3 |
34 | |
35 | =cut |
b49c4318 |
36 | |
ec3f9144 |
37 | # Return graph -> nodeid -> { key1/val1, key2/val2, key3/val3 ... } |
38 | # -> edgeid -> { source, target, wit1/val1, wit2/val2 ...} |
4a8828f0 |
39 | |
e867486f |
40 | sub graphml_parse { |
dfc37e38 |
41 | my( $opts ) = @_; |
ec3f9144 |
42 | |
43 | my $graph_hash = { 'nodes' => [], |
910a0a6d |
44 | 'edges' => [] }; |
e867486f |
45 | |
b49c4318 |
46 | my $parser = XML::LibXML->new(); |
dfc37e38 |
47 | my $doc; |
48 | if( exists $opts->{'string'} ) { |
49 | $doc = $parser->parse_string( $opts->{'string'} ); |
50 | } elsif ( exists $opts->{'file'} ) { |
51 | $doc = $parser->parse_file( $opts->{'file'} ); |
52 | } else { |
53 | warn "Could not find string or file option to parse"; |
54 | return; |
55 | } |
56 | |
e867486f |
57 | my( $graphattr, $nodedata, $witnesses ) = ( {}, {}, {} ); |
8e1394aa |
58 | my $graphml = $doc->documentElement(); |
4a8828f0 |
59 | $xpc = XML::LibXML::XPathContext->new( $graphml ); |
b49c4318 |
60 | $xpc->registerNs( 'g', 'http://graphml.graphdrawing.org/xmlns' ); |
61 | |
62 | # First get the ID keys, for witnesses and for collation data |
b49c4318 |
63 | foreach my $k ( $xpc->findnodes( '//g:key' ) ) { |
910a0a6d |
64 | # Each key has a 'for' attribute; the edge keys are witnesses, and |
65 | # the node keys contain an ID and string for each node. |
66 | my $keyid = $k->getAttribute( 'id' ); |
67 | my $keyname = $k->getAttribute( 'attr.name' ); |
68 | |
e309421a |
69 | # Keep track of the XML identifiers for the data carried |
70 | # in each node element. |
71 | my $dtype = $k->getAttribute( 'for' ); |
72 | if( $dtype eq 'graph' ) { |
73 | $graphattr->{$keyid} = $keyname; |
74 | } elsif( $dtype eq 'node' ) { |
75 | $nodedata->{$keyid} = $keyname; |
910a0a6d |
76 | } else { |
77 | $witnesses->{$keyid} = $keyname; |
78 | } |
b49c4318 |
79 | } |
80 | |
81 | my $graph_el = $xpc->find( '/g:graphml/g:graph' )->[0]; |
e3196b2a |
82 | $graph_hash->{'name'} = $graph_el->getAttribute( 'id' ); |
b49c4318 |
83 | |
ec3f9144 |
84 | my $node_reg = {}; |
e309421a |
85 | |
86 | # Read in graph globals (if any). |
0068967c |
87 | # print STDERR "Reading graphml global data\n"; |
e309421a |
88 | foreach my $dkey ( keys %$graphattr ) { |
89 | my $keyname = $graphattr->{$dkey}; |
90 | my $keyvalue = _lookup_node_data( $graph_el, $dkey ); |
91 | $graph_hash->{'global'}->{$keyname} = $keyvalue; |
92 | } |
ec3f9144 |
93 | |
94c00c71 |
94 | # Add the nodes to the graph hash. |
0068967c |
95 | # print STDERR "Reading graphml nodes\n"; |
b49c4318 |
96 | my @nodes = $xpc->findnodes( '//g:node' ); |
97 | foreach my $n ( @nodes ) { |
910a0a6d |
98 | # Could use a better way of registering these |
99 | my $node_hash = {}; |
100 | foreach my $dkey ( keys %$nodedata ) { |
101 | my $keyname = $nodedata->{$dkey}; |
102 | my $keyvalue = _lookup_node_data( $n, $dkey ); |
103 | $node_hash->{$keyname} = $keyvalue if defined $keyvalue; |
104 | } |
105 | $node_reg->{$n->getAttribute( 'id' )} = $node_hash; |
106 | push( @{$graph_hash->{'nodes'}}, $node_hash ); |
b49c4318 |
107 | } |
910a0a6d |
108 | |
ec3f9144 |
109 | # Now add the edges, and cross-ref with the node objects. |
0068967c |
110 | # print STDERR "Reading graphml edges\n"; |
b49c4318 |
111 | my @edges = $xpc->findnodes( '//g:edge' ); |
112 | foreach my $e ( @edges ) { |
910a0a6d |
113 | my $from = $e->getAttribute('source'); |
114 | my $to = $e->getAttribute('target'); |
115 | |
116 | # We don't know whether the edge data is one per witness |
117 | # or one per witness type, or something else. So we just |
118 | # save it and let our calling parser decide. |
119 | my $edge_hash = { |
120 | 'source' => $node_reg->{$from}, |
121 | 'target' => $node_reg->{$to}, |
122 | }; |
123 | foreach my $wkey( keys %$witnesses ) { |
124 | my $wname = $witnesses->{$wkey}; |
125 | my $wlabel = _lookup_node_data( $e, $wkey ); |
126 | $edge_hash->{$wname} = $wlabel if $wlabel; |
127 | } |
128 | push( @{$graph_hash->{'edges'}}, $edge_hash ); |
b49c4318 |
129 | } |
ec3f9144 |
130 | return $graph_hash; |
4a8828f0 |
131 | } |
b49c4318 |
132 | |
e867486f |
133 | |
4a8828f0 |
134 | sub _lookup_node_data { |
ec3f9144 |
135 | my( $xmlnode, $key ) = @_; |
4a8828f0 |
136 | my $lookup_xpath = './g:data[@key="%s"]/child::text()'; |
94c00c71 |
137 | my $data = $xpc->find( sprintf( $lookup_xpath, $key ), $xmlnode ); |
138 | # If we get back an empty nodelist, we return undef. |
139 | if( ref( $data ) ) { |
140 | return undef unless $data->size; |
141 | return $data->to_literal->value; |
142 | } |
143 | # Otherwise we got back a value. Return it. |
4a8828f0 |
144 | return $data; |
b49c4318 |
145 | } |
146 | |
2ceca8c3 |
147 | =back |
148 | |
149 | =head1 LICENSE |
150 | |
151 | This package is free software and is provided "as is" without express |
152 | or implied warranty. You can redistribute it and/or modify it under |
153 | the same terms as Perl itself. |
154 | |
155 | =head1 AUTHOR |
156 | |
157 | Tara L Andrews, aurum@cpan.org |
158 | |
159 | =cut |
160 | |
b49c4318 |
161 | 1; |