[dbsrgits/SQL-Translator.git] / lib / SQL / Translator / Producer / XML / SQLFairy.pm

package SQL::Translator::Producer::XML::SQLFairy;

# -------------------------------------------------------------------
# Copyright (C) 2003 Ken Y. Clark <kclark@cpan.org>,
#                    darren chamberlain <darren@cpan.org>,
#                    Chris Mungall <cjm@fruitfly.org>,
#                    Mark Addison <mark.addison@itn.co.uk>.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; version 2.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
# 02111-1307  USA
# -------------------------------------------------------------------

=pod

=head1 NAME

SQL::Translator::Producer::XML::SQLFairy - SQLFairy's default XML format

=head1 SYNOPSIS

  use SQL::Translator;

  my $t              = SQL::Translator->new(
      from           => 'MySQL',
      to             => 'XML-SQLFairy',
      filename       => 'schema.sql',
      show_warnings  => 1,
  );

  print $t->translate;

=head1 DESCRIPTION

Creates XML output of a schema, in the flavor of XML used natively by the
SQLFairy project (L<SQL::Translator>). This format is detailed here.

The XML lives in the C<http://sqlfairy.sourceforge.net/sqlfairy.xml> namespace.
With a root element of <schema>.

Objects in the schema are mapped to tags of the same name as the objects class
(all lowercase).

The attributes of the objects (e.g. $field->name) are mapped to attributes of
the tag, except for sql, comments and action, which get mapped to child data
elements.

List valued attributes (such as the list of fields in an index)
get mapped to comma seperated lists of values in the attribute.

Child objects, such as a tables fields, get mapped to child tags wrapped in a
set of container tags using the plural of their contained classes name.

An objects's extra attribute (a hash of arbitary data) is
mapped to a tag called extra, with the hash of data as attributes, sorted into
alphabetical order.

e.g.

    <schema name="" database=""
      xmlns="http://sqlfairy.sourceforge.net/sqlfairy.xml">

      <tables>
        <table name="Story" order="1">
          <fields>
            <field name="id" data_type="BIGINT" size="20"
              is_nullable="0" is_auto_increment="1" is_primary_key="1"
              is_foreign_key="0" order="3">
              <extra ZEROFILL="1" />
              <comments></comments>
            </field>
            <field name="created" data_type="datetime" size="0"
              is_nullable="1" is_auto_increment="0" is_primary_key="0"
              is_foreign_key="0" order="1">
              <extra />
              <comments></comments>
            </field>
            ...
          </fields>
          <indices>
            <index name="foobar" type="NORMAL" fields="foo,bar" options="" />
          </indices>
        </table>
      </tables>

      <views>
        <view name="email_list" fields="email" order="1">
          <sql>SELECT email FROM Basic WHERE email IS NOT NULL</sql>
        </view>
      </views>

    </schema>

To see a complete example of the XML translate one of your schema :)

  $ sqlt -f MySQL -t XML-SQLFairy schema.sql

=head1 ARGS

=over 4

=item add_prefix

Set to true to use the default namespace prefix of 'sqlf', instead of using
the default namespace for
C<http://sqlfairy.sourceforge.net/sqlfairy.xml namespace>

e.g.

 <!-- add_prefix=0 -->
 <field name="foo" />

 <!-- add_prefix=1 -->
 <sqlf:field name="foo" />

=item prefix

Set to the namespace prefix you want to use for the
C<http://sqlfairy.sourceforge.net/sqlfairy.xml namespace>

e.g.

 <!-- prefix='foo' -->
 <foo:field name="foo" />

=item newlines

If true (the default) inserts newlines around the XML, otherwise the schema is
written on one line.

=item indent

When using newlines the number of whitespace characters to use as the indent.
Default is 2, set to 0 to turn off indenting.

=back

=head1 LEGACY FORMAT

The previous version of the SQLFairy XML allowed the attributes of the the
schema objects to be written as either xml attributes or as data elements, in
any combination. The old producer could produce attribute only or data element
only versions. While this allowed for lots of flexibility in writing the XML
the result is a great many possible XML formats, not so good for DTD writing,
XPathing etc! So we have moved to a fixed version described above.

This version of the producer will now only produce the new style XML.
To convert your old format files simply pass them through the translator :)

 $ sqlt -f XML-SQLFairy -t XML-SQLFairy schema-old.xml > schema-new.xml

=cut

use strict;
use vars qw[ $VERSION @EXPORT_OK ];
$VERSION = '1.59';

use Exporter;
use base qw(Exporter);
@EXPORT_OK = qw(produce);

use IO::Scalar;
use SQL::Translator::Utils qw(header_comment debug);
BEGIN {
    # Will someone fix XML::Writer already?
    local $^W = 0;
    require XML::Writer;
    import XML::Writer;
}

# Which schema object attributes (methods) to write as xml elements rather than
# as attributes. e.g. <comments>blah, blah...</comments>
my @MAP_AS_ELEMENTS = qw/sql comments action extra/;


my $Namespace = 'http://sqlfairy.sourceforge.net/sqlfairy.xml';
my $Name      = 'sqlf';
my $PArgs     = {};

sub produce {
    my $translator  = shift;
    my $schema      = $translator->schema;
    $PArgs          = $translator->producer_args;
    my $newlines    = defined $PArgs->{newlines} ? $PArgs->{newlines} : 1;
    my $indent      = defined $PArgs->{indent}   ? $PArgs->{indent}   : 2;
    my $io          = IO::Scalar->new;

    # Setup the XML::Writer and set the namespace
    my $prefix = "";
    $prefix    = $Name            if $PArgs->{add_prefix};
    $prefix    = $PArgs->{prefix} if $PArgs->{prefix};
    my $xml         = XML::Writer->new(
        OUTPUT      => $io,
        NAMESPACES  => 1,
        PREFIX_MAP  => { $Namespace => $prefix },
        DATA_MODE   => $newlines,
        DATA_INDENT => $indent,
    );

    # Start the document
    $xml->xmlDecl('UTF-8');
    $xml->comment(header_comment('', ''));
    xml_obj($xml, $schema,
        tag => "schema", methods => [qw/name database extra/], end_tag => 0 );

    #
    # Table
    #
    $xml->startTag( [ $Namespace => "tables" ] );
    for my $table ( $schema->get_tables ) {
        debug "Table:",$table->name;
        xml_obj($xml, $table,
             tag => "table",
             methods => [qw/name order extra/],
             end_tag => 0
         );

        #
        # Fields
        #
        xml_obj_children( $xml, $table,
            tag   => 'field',
            methods =>[qw/
                name data_type size is_nullable default_value is_auto_increment
                is_primary_key is_foreign_key extra comments order
            /],
        );

        #
        # Indices
        #
        xml_obj_children( $xml, $table,
            tag   => 'index',
            collection_tag => "indices",
            methods => [qw/name type fields options extra/],
        );

        #
        # Constraints
        #
        xml_obj_children( $xml, $table,
            tag   => 'constraint',
            methods => [qw/
                name type fields reference_table reference_fields
                on_delete on_update match_type expression options deferrable
                extra
            /],
        );

        #
        # Comments
        #
        xml_obj_children( $xml, $table,
            tag   => 'comment',
            collection_tag => "comments",
            methods => [qw/
                comments
            /],
        );

        $xml->endTag( [ $Namespace => 'table' ] );
    }
    $xml->endTag( [ $Namespace => 'tables' ] );

    #
    # Views
    #
    xml_obj_children( $xml, $schema,
        tag   => 'view',
        methods => [qw/name sql fields order extra/],
    );

    #
    # Tiggers
    #
    xml_obj_children( $xml, $schema,
        tag    => 'trigger',
        methods => [qw/name database_events action on_table perform_action_when
            fields order extra/],
    );

    #
    # Procedures
    #
    xml_obj_children( $xml, $schema,
        tag   => 'procedure',
        methods => [qw/name sql parameters owner comments order extra/],
    );

    $xml->endTag([ $Namespace => 'schema' ]);
    $xml->end;

    return $io;
}


#
# Takes and XML::Write object, Schema::* parent object, the tag name,
# the collection name and a list of methods (of the children) to write as XML.
# The collection name defaults to the name with an s on the end and is used to
# work out the method to get the children with. eg a name of 'foo' gives a
# collection of foos and gets the members using ->get_foos.
#
sub xml_obj_children {
    my ($xml,$parent) = (shift,shift);
    my %args = @_;
    my ($name,$collection_name,$methods)
        = @args{qw/tag collection_tag methods/};
    $collection_name ||= "${name}s";

    my $meth;
    if ( $collection_name eq 'comments' ) {
      $meth = 'comments';
    } else {
      $meth = "get_$collection_name";
    }

    my @kids = $parent->$meth;
    #@kids || return;
    $xml->startTag( [ $Namespace => $collection_name ] );

    for my $obj ( @kids ) {
        if ( $collection_name eq 'comments' ){
            $xml->dataElement( [ $Namespace => 'comment' ], $obj );
        } else {
            xml_obj($xml, $obj,
                tag     => "$name",
                end_tag => 1,
                methods => $methods,
            );
        }
    }
    $xml->endTag( [ $Namespace => $collection_name ] );
}

#
# Takes an XML::Writer, Schema::* object and list of method names
# and writes the obect out as XML. All methods values are written as attributes
# except for the methods listed in @MAP_AS_ELEMENTS which get written as child
# data elements.
#
# The attributes/tags are written in the same order as the method names are
# passed.
#
# TODO
# - Should the Namespace be passed in instead of global? Pass in the same
#   as Writer ie [ NS => TAGNAME ]
#
my $elements_re = join("|", @MAP_AS_ELEMENTS);
$elements_re = qr/^($elements_re)$/;
sub xml_obj {
    my ($xml, $obj, %args) = @_;
    my $tag                = $args{'tag'}              || '';
    my $end_tag            = $args{'end_tag'}          || '';
    my @meths              = @{ $args{'methods'} };
    my $empty_tag          = 0;

    # Use array to ensure consistant (ie not hash) ordering of attribs
    # The order comes from the meths list passed in.
    my @tags;
    my @attr;
    foreach ( grep { defined $obj->$_ } @meths ) {
        my $what = m/$elements_re/ ? \@tags : \@attr;
        my $val = $_ eq 'extra'
            ? { $obj->$_ }
            : $obj->$_;
        $val = ref $val eq 'ARRAY' ? join(',', @$val) : $val;
        push @$what, $_ => $val;
    };
    my $child_tags = @tags;
    $end_tag && !$child_tags
        ? $xml->emptyTag( [ $Namespace => $tag ], @attr )
        : $xml->startTag( [ $Namespace => $tag ], @attr );
    while ( my ($name,$val) = splice @tags,0,2 ) {
        if ( ref $val eq 'HASH' ) {
             $xml->emptyTag( [ $Namespace => $name ],
                 map { ($_, $val->{$_}) } sort keys %$val );
        }
        else {
            $xml->dataElement( [ $Namespace => $name ], $val );
        }
    }
    $xml->endTag( [ $Namespace => $tag ] ) if $child_tags && $end_tag;
}

1;

# -------------------------------------------------------------------
# The eyes of fire, the nostrils of air,
# The mouth of water, the beard of earth.
# William Blake
# -------------------------------------------------------------------

=pod

=head1 AUTHORS

Ken Y. Clark E<lt>kclark@cpan.orgE<gt>,
Darren Chamberlain E<lt>darren@cpan.orgE<gt>,
Mark Addison E<lt>mark.addison@itn.co.ukE<gt>.

=head1 SEE ALSO

L<perl(1)>, L<SQL::Translator>, L<SQL::Translator::Parser::XML::SQLFairy>,
L<SQL::Translator::Schema>, L<XML::Writer>.

=cut
Commit	Line	Data
0a689100	1	package SQL::Translator::Producer::XML::SQLFairy;
	2
	3	# -------------------------------------------------------------------
0a689100	4	# Copyright (C) 2003 Ken Y. Clark <kclark@cpan.org>,
	5	# darren chamberlain <darren@cpan.org>,
	6	# Chris Mungall <cjm@fruitfly.org>,
	7	# Mark Addison <mark.addison@itn.co.uk>.
	8	#
	9	# This program is free software; you can redistribute it and/or
	10	# modify it under the terms of the GNU General Public License as
	11	# published by the Free Software Foundation; version 2.
	12	#
	13	# This program is distributed in the hope that it will be useful, but
	14	# WITHOUT ANY WARRANTY; without even the implied warranty of
	15	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	# General Public License for more details.
	17	#
	18	# You should have received a copy of the GNU General Public License
	19	# along with this program; if not, write to the Free Software
	20	# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	21	# 02111-1307 USA
	22	# -------------------------------------------------------------------
	23
	24	=pod
	25
	26	=head1 NAME
	27
a7d50b44	28	SQL::Translator::Producer::XML::SQLFairy - SQLFairy's default XML format
0a689100	29
	30	=head1 SYNOPSIS
	31
	32	use SQL::Translator;
	33
	34	my $t = SQL::Translator->new(
	35	from => 'MySQL',
a7d50b44	36	to => 'XML-SQLFairy',
0a689100	37	filename => 'schema.sql',
0a689100	38	show_warnings => 1,
0a689100	39	);
	40
	41	print $t->translate;
	42
b89a67a0	43	=head1 DESCRIPTION
0a689100	44
91f28468	45	Creates XML output of a schema, in the flavor of XML used natively by the
91f28468	46	SQLFairy project (L<SQL::Translator>). This format is detailed here.
0a689100	47
91f28468	48	The XML lives in the C<http://sqlfairy.sourceforge.net/sqlfairy.xml> namespace.
b89a67a0	49	With a root element of <schema>.
0a689100	50
91f28468	51	Objects in the schema are mapped to tags of the same name as the objects class
91f28468	52	(all lowercase).
0a689100	53
b89a67a0	54	The attributes of the objects (e.g. $field->name) are mapped to attributes of
	55	the tag, except for sql, comments and action, which get mapped to child data
	56	elements.
0a689100	57
b89a67a0	58	List valued attributes (such as the list of fields in an index)
91f28468	59	get mapped to comma seperated lists of values in the attribute.
0a689100	60
b89a67a0	61	Child objects, such as a tables fields, get mapped to child tags wrapped in a
b89a67a0	62	set of container tags using the plural of their contained classes name.
0a689100	63
0eebe059	64	An objects's extra attribute (a hash of arbitary data) is
e0a0c3e1	65	mapped to a tag called extra, with the hash of data as attributes, sorted into
	66	alphabetical order.
	67
b89a67a0	68	e.g.
0a689100	69
b89a67a0	70	<schema name="" database=""
b89a67a0	71	xmlns="http://sqlfairy.sourceforge.net/sqlfairy.xml">
0a689100	72
91f28468	73	<tables>
	74	<table name="Story" order="1">
	75	<fields>
	76	<field name="id" data_type="BIGINT" size="20"
	77	is_nullable="0" is_auto_increment="1" is_primary_key="1"
	78	is_foreign_key="0" order="3">
	79	<extra ZEROFILL="1" />
	80	<comments></comments>
	81	</field>
	82	<field name="created" data_type="datetime" size="0"
	83	is_nullable="1" is_auto_increment="0" is_primary_key="0"
	84	is_foreign_key="0" order="1">
	85	<extra />
	86	<comments></comments>
	87	</field>
	88	...
	89	</fields>
	90	<indices>
	91	<index name="foobar" type="NORMAL" fields="foo,bar" options="" />
	92	</indices>
	93	</table>
	94	</tables>
	95
	96	<views>
	97	<view name="email_list" fields="email" order="1">
	98	<sql>SELECT email FROM Basic WHERE email IS NOT NULL</sql>
	99	</view>
	100	</views>
b89a67a0	101
	102	</schema>
	103
	104	To see a complete example of the XML translate one of your schema :)
	105
	106	$ sqlt -f MySQL -t XML-SQLFairy schema.sql
	107
	108	=head1 ARGS
0a689100	109
983ed646	110	=over 4
	111
	112	=item add_prefix
	113
	114	Set to true to use the default namespace prefix of 'sqlf', instead of using
	115	the default namespace for
	116	C<http://sqlfairy.sourceforge.net/sqlfairy.xml namespace>
	117
	118	e.g.
	119
	120	<!-- add_prefix=0 -->
	121	<field name="foo" />
	122
	123	<!-- add_prefix=1 -->
	124	<sqlf:field name="foo" />
	125
	126	=item prefix
	127
	128	Set to the namespace prefix you want to use for the
	129	C<http://sqlfairy.sourceforge.net/sqlfairy.xml namespace>
	130
	131	e.g.
	132
	133	<!-- prefix='foo' -->
	134	<foo:field name="foo" />
	135
e0a0c3e1	136	=item newlines
	137
	138	If true (the default) inserts newlines around the XML, otherwise the schema is
	139	written on one line.
	140
	141	=item indent
	142
	143	When using newlines the number of whitespace characters to use as the indent.
	144	Default is 2, set to 0 to turn off indenting.
	145
983ed646	146	=back
0a689100	147
4a268a6c	148	=head1 LEGACY FORMAT
	149
	150	The previous version of the SQLFairy XML allowed the attributes of the the
	151	schema objects to be written as either xml attributes or as data elements, in
	152	any combination. The old producer could produce attribute only or data element
	153	only versions. While this allowed for lots of flexibility in writing the XML
	154	the result is a great many possible XML formats, not so good for DTD writing,
	155	XPathing etc! So we have moved to a fixed version described above.
	156
	157	This version of the producer will now only produce the new style XML.
91f28468	158	To convert your old format files simply pass them through the translator :)
4a268a6c	159
91f28468	160	$ sqlt -f XML-SQLFairy -t XML-SQLFairy schema-old.xml > schema-new.xml
4a268a6c	161
0a689100	162	=cut
	163
	164	use strict;
da06ac74	165	use vars qw[ $VERSION @EXPORT_OK ];
4ab3763d	166	$VERSION = '1.59';
0a689100	167
	168	use Exporter;
	169	use base qw(Exporter);
	170	@EXPORT_OK = qw(produce);
	171
	172	use IO::Scalar;
	173	use SQL::Translator::Utils qw(header_comment debug);
f135f8f9	174	BEGIN {
	175	# Will someone fix XML::Writer already?
	176	local $^W = 0;
	177	require XML::Writer;
	178	import XML::Writer;
	179	}
0a689100	180
23735f6a	181	# Which schema object attributes (methods) to write as xml elements rather than
	182	# as attributes. e.g. <comments>blah, blah...</comments>
	183	my @MAP_AS_ELEMENTS = qw/sql comments action extra/;
	184
	185
	186
0a689100	187	my $Namespace = 'http://sqlfairy.sourceforge.net/sqlfairy.xml';
b89a67a0	188	my $Name = 'sqlf';
375f0be1	189	my $PArgs = {};
0a689100	190
	191	sub produce {
	192	my $translator = shift;
	193	my $schema = $translator->schema;
	194	$PArgs = $translator->producer_args;
983ed646	195	my $newlines = defined $PArgs->{newlines} ? $PArgs->{newlines} : 1;
983ed646	196	my $indent = defined $PArgs->{indent} ? $PArgs->{indent} : 2;
0a689100	197	my $io = IO::Scalar->new;
983ed646	198
23735f6a	199	# Setup the XML::Writer and set the namespace
983ed646	200	my $prefix = "";
	201	$prefix = $Name if $PArgs->{add_prefix};
	202	$prefix = $PArgs->{prefix} if $PArgs->{prefix};
0a689100	203	my $xml = XML::Writer->new(
	204	OUTPUT => $io,
	205	NAMESPACES => 1,
983ed646	206	PREFIX_MAP => { $Namespace => $prefix },
	207	DATA_MODE => $newlines,
	208	DATA_INDENT => $indent,
0a689100	209	);
0a689100	210
23735f6a	211	# Start the document
0a689100	212	$xml->xmlDecl('UTF-8');
0a689100	213	$xml->comment(header_comment('', ''));
1caf2bb2	214	xml_obj($xml, $schema,
0eebe059	215	tag => "schema", methods => [qw/name database extra/], end_tag => 0 );
0a689100	216
	217	#
	218	# Table
	219	#
87c5565e	220	$xml->startTag( [ $Namespace => "tables" ] );
0a689100	221	for my $table ( $schema->get_tables ) {
0a689100	222	debug "Table:",$table->name;
d3422086	223	xml_obj($xml, $table,
87c5565e	224	tag => "table",
0eebe059	225	methods => [qw/name order extra/],
87c5565e	226	end_tag => 0
87c5565e	227	);
0a689100	228
	229	#
	230	# Fields
	231	#
87c5565e	232	xml_obj_children( $xml, $table,
	233	tag => 'field',
	234	methods =>[qw/
	235	name data_type size is_nullable default_value is_auto_increment
	236	is_primary_key is_foreign_key extra comments order
	237	/],
	238	);
0a689100	239
	240	#
	241	# Indices
	242	#
87c5565e	243	xml_obj_children( $xml, $table,
	244	tag => 'index',
	245	collection_tag => "indices",
0eebe059	246	methods => [qw/name type fields options extra/],
87c5565e	247	);
0a689100	248
	249	#
	250	# Constraints
	251	#
87c5565e	252	xml_obj_children( $xml, $table,
	253	tag => 'constraint',
	254	methods => [qw/
	255	name type fields reference_table reference_fields
	256	on_delete on_update match_type expression options deferrable
0eebe059	257	extra
87c5565e	258	/],
87c5565e	259	);
0a689100	260
7c71eaab	261	#
	262	# Comments
	263	#
	264	xml_obj_children( $xml, $table,
	265	tag => 'comment',
	266	collection_tag => "comments",
	267	methods => [qw/
	268	comments
	269	/],
	270	);
	271
0a689100	272	$xml->endTag( [ $Namespace => 'table' ] );
0a689100	273	}
87c5565e	274	$xml->endTag( [ $Namespace => 'tables' ] );
d3422086	275
1e3867bf	276	#
	277	# Views
	278	#
87c5565e	279	xml_obj_children( $xml, $schema,
87c5565e	280	tag => 'view',
0eebe059	281	methods => [qw/name sql fields order extra/],
87c5565e	282	);
d3422086	283
1e3867bf	284	#
	285	# Tiggers
	286	#
87c5565e	287	xml_obj_children( $xml, $schema,
87c5565e	288	tag => 'trigger',
222094af	289	methods => [qw/name database_events action on_table perform_action_when
0eebe059	290	fields order extra/],
87c5565e	291	);
0a689100	292
1e3867bf	293	#
	294	# Procedures
	295	#
87c5565e	296	xml_obj_children( $xml, $schema,
87c5565e	297	tag => 'procedure',
0eebe059	298	methods => [qw/name sql parameters owner comments order extra/],
87c5565e	299	);
d3422086	300
0a689100	301	$xml->endTag([ $Namespace => 'schema' ]);
	302	$xml->end;
	303
	304	return $io;
	305	}
	306
87c5565e	307
	308	#
	309	# Takes and XML::Write object, Schema::* parent object, the tag name,
	310	# the collection name and a list of methods (of the children) to write as XML.
	311	# The collection name defaults to the name with an s on the end and is used to
	312	# work out the method to get the children with. eg a name of 'foo' gives a
	313	# collection of foos and gets the members using ->get_foos.
	314	#
	315	sub xml_obj_children {
	316	my ($xml,$parent) = (shift,shift);
	317	my %args = @_;
	318	my ($name,$collection_name,$methods)
	319	= @args{qw/tag collection_tag methods/};
	320	$collection_name \|\|= "${name}s";
7c71eaab	321
	322	my $meth;
	323	if ( $collection_name eq 'comments' ) {
	324	$meth = 'comments';
	325	} else {
	326	$meth = "get_$collection_name";
	327	}
87c5565e	328
	329	my @kids = $parent->$meth;
	330	#@kids \|\| return;
	331	$xml->startTag( [ $Namespace => $collection_name ] );
7c71eaab	332
87c5565e	333	for my $obj ( @kids ) {
7c71eaab	334	if ( $collection_name eq 'comments' ){
	335	$xml->dataElement( [ $Namespace => 'comment' ], $obj );
	336	} else {
	337	xml_obj($xml, $obj,
	338	tag => "$name",
	339	end_tag => 1,
	340	methods => $methods,
	341	);
	342	}
87c5565e	343	}
	344	$xml->endTag( [ $Namespace => $collection_name ] );
	345	}
	346
1caf2bb2	347	#
23735f6a	348	# Takes an XML::Writer, Schema::* object and list of method names
b89a67a0	349	# and writes the obect out as XML. All methods values are written as attributes
87c5565e	350	# except for the methods listed in @MAP_AS_ELEMENTS which get written as child
87c5565e	351	# data elements.
b89a67a0	352	#
23735f6a	353	# The attributes/tags are written in the same order as the method names are
b89a67a0	354	# passed.
	355	#
	356	# TODO
1caf2bb2	357	# - Should the Namespace be passed in instead of global? Pass in the same
	358	# as Writer ie [ NS => TAGNAME ]
	359	#
23735f6a	360	my $elements_re = join("\|", @MAP_AS_ELEMENTS);
23735f6a	361	$elements_re = qr/^($elements_re)$/;
0a689100	362	sub xml_obj {
d3422086	363	my ($xml, $obj, %args) = @_;
	364	my $tag = $args{'tag'} \|\| '';
	365	my $end_tag = $args{'end_tag'} \|\| '';
d3422086	366	my @meths = @{ $args{'methods'} };
	367	my $empty_tag = 0;
	368
b89a67a0	369	# Use array to ensure consistant (ie not hash) ordering of attribs
	370	# The order comes from the meths list passed in.
	371	my @tags;
	372	my @attr;
	373	foreach ( grep { defined $obj->$_ } @meths ) {
23735f6a	374	my $what = m/$elements_re/ ? \@tags : \@attr;
e0a0c3e1	375	my $val = $_ eq 'extra'
	376	? { $obj->$_ }
	377	: $obj->$_;
0a689100	378	$val = ref $val eq 'ARRAY' ? join(',', @$val) : $val;
b89a67a0	379	push @$what, $_ => $val;
	380	};
	381	my $child_tags = @tags;
	382	$end_tag && !$child_tags
	383	? $xml->emptyTag( [ $Namespace => $tag ], @attr )
	384	: $xml->startTag( [ $Namespace => $tag ], @attr );
	385	while ( my ($name,$val) = splice @tags,0,2 ) {
e0a0c3e1	386	if ( ref $val eq 'HASH' ) {
	387	$xml->emptyTag( [ $Namespace => $name ],
	388	map { ($_, $val->{$_}) } sort keys %$val );
	389	}
	390	else {
	391	$xml->dataElement( [ $Namespace => $name ], $val );
	392	}
0a689100	393	}
b89a67a0	394	$xml->endTag( [ $Namespace => $tag ] ) if $child_tags && $end_tag;
0a689100	395	}
	396
	397	1;
	398
	399	# -------------------------------------------------------------------
	400	# The eyes of fire, the nostrils of air,
	401	# The mouth of water, the beard of earth.
	402	# William Blake
	403	# -------------------------------------------------------------------
	404
	405	=pod
	406
	407	=head1 AUTHORS
	408
d3422086	409	Ken Y. Clark E<lt>kclark@cpan.orgE<gt>,
d3422086	410	Darren Chamberlain E<lt>darren@cpan.orgE<gt>,
0a689100	411	Mark Addison E<lt>mark.addison@itn.co.ukE<gt>.
	412
	413	=head1 SEE ALSO
	414
91f28468	415	L<perl(1)>, L<SQL::Translator>, L<SQL::Translator::Parser::XML::SQLFairy>,
91f28468	416	L<SQL::Translator::Schema>, L<XML::Writer>.
0a689100	417
0a689100	418	=cut