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

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

# -------------------------------------------------------------------
# $Id: SQLFairy.pm,v 1.17 2004-08-19 14:09:00 grommit Exp $
# -------------------------------------------------------------------
# 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,
      add_drop_table => 1,
  );

  print $t->translate;

=head1 DESCRIPTION

Creates XML output of a schema, in SQLFairy format XML.

The XML lives in the 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.

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 a comma seperated list 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.

L<SQL::Translator::Schema::Field>'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">

      <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>

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

    </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 ];
$VERSION = sprintf "%d.%02d", q$Revision: 1.17 $ =~ /(\d+)\.(\d+)/;

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/], 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/],
             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/],
        );

        #
        # 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
            /],
        );

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

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

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

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

    $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 $meth = "get_$collection_name";

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

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

=cut
Commit	Line	Data
0a689100	1	package SQL::Translator::Producer::XML::SQLFairy;
	2
	3	# -------------------------------------------------------------------
87c5565e	4	# $Id: SQLFairy.pm,v 1.17 2004-08-19 14:09:00 grommit Exp $
0a689100	5	# -------------------------------------------------------------------
	6	# Copyright (C) 2003 Ken Y. Clark <kclark@cpan.org>,
	7	# darren chamberlain <darren@cpan.org>,
	8	# Chris Mungall <cjm@fruitfly.org>,
	9	# Mark Addison <mark.addison@itn.co.uk>.
	10	#
	11	# This program is free software; you can redistribute it and/or
	12	# modify it under the terms of the GNU General Public License as
	13	# published by the Free Software Foundation; version 2.
	14	#
	15	# This program is distributed in the hope that it will be useful, but
	16	# WITHOUT ANY WARRANTY; without even the implied warranty of
	17	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	# General Public License for more details.
	19	#
	20	# You should have received a copy of the GNU General Public License
	21	# along with this program; if not, write to the Free Software
	22	# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	23	# 02111-1307 USA
	24	# -------------------------------------------------------------------
	25
	26	=pod
	27
	28	=head1 NAME
	29
a7d50b44	30	SQL::Translator::Producer::XML::SQLFairy - SQLFairy's default XML format
0a689100	31
	32	=head1 SYNOPSIS
	33
	34	use SQL::Translator;
	35
	36	my $t = SQL::Translator->new(
	37	from => 'MySQL',
a7d50b44	38	to => 'XML-SQLFairy',
0a689100	39	filename => 'schema.sql',
	40	show_warnings => 1,
	41	add_drop_table => 1,
	42	);
	43
	44	print $t->translate;
	45
b89a67a0	46	=head1 DESCRIPTION
0a689100	47
b89a67a0	48	Creates XML output of a schema, in SQLFairy format XML.
0a689100	49
b89a67a0	50	The XML lives in the http://sqlfairy.sourceforge.net/sqlfairy.xml namespace.
b89a67a0	51	With a root element of <schema>.
0a689100	52
b89a67a0	53	Objects in the schema are mapped to tags of the same name as the objects class.
0a689100	54
b89a67a0	55	The attributes of the objects (e.g. $field->name) are mapped to attributes of
	56	the tag, except for sql, comments and action, which get mapped to child data
	57	elements.
0a689100	58
b89a67a0	59	List valued attributes (such as the list of fields in an index)
b89a67a0	60	get mapped to a comma seperated list of values in the attribute.
0a689100	61
b89a67a0	62	Child objects, such as a tables fields, get mapped to child tags wrapped in a
b89a67a0	63	set of container tags using the plural of their contained classes name.
0a689100	64
e0a0c3e1	65	L<SQL::Translator::Schema::Field>'s extra attribute (a hash of arbitary data) is
	66	mapped to a tag called extra, with the hash of data as attributes, sorted into
	67	alphabetical order.
	68
b89a67a0	69	e.g.
0a689100	70
b89a67a0	71	<schema name="" database=""
b89a67a0	72	xmlns="http://sqlfairy.sourceforge.net/sqlfairy.xml">
0a689100	73
b89a67a0	74	<table name="Story" order="1">
0a689100	75
b89a67a0	76	<fields>
b89a67a0	77	<field name="id" data_type="BIGINT" size="20"
	78	is_nullable="0" is_auto_increment="1" is_primary_key="1"
	79	is_foreign_key="0" order="3">
e0a0c3e1	80	<extra ZEROFILL="1" />
	81	<comments></comments>
	82	</field>
	83	<field name="created" data_type="datetime" size="0"
	84	is_nullable="1" is_auto_increment="0" is_primary_key="0"
	85	is_foreign_key="0" order="1">
	86	<extra />
b89a67a0	87	<comments></comments>
	88	</field>
	89	...
	90	</fields>
	91
	92	<indices>
	93	<index name="foobar" type="NORMAL" fields="foo,bar" options="" />
	94	</indices>
	95
	96	</table>
	97
	98	<view name="email_list" fields="email" order="1">
	99	<sql>SELECT email FROM Basic WHERE email IS NOT NULL</sql>
	100	</view>
	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.
	158	To convert your old format files simply pass them through the translator;
	159
	160	sqlt -f XML-SQLFairy -t XML-SQLFairy schema-old.xml > schema-new.xml
	161
0a689100	162	=cut
	163
	164	use strict;
	165	use vars qw[ $VERSION @EXPORT_OK ];
87c5565e	166	$VERSION = sprintf "%d.%02d", q$Revision: 1.17 $ =~ /(\d+)\.(\d+)/;
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,
1caf2bb2	215	tag => "schema", methods => [qw/name database/], 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",
	225	methods => [qw/name order/],
	226	end_tag => 0
	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",
	246	methods => [qw/name type fields options/],
	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
	257	/],
	258	);
0a689100	259
	260	$xml->endTag( [ $Namespace => 'table' ] );
	261	}
87c5565e	262	$xml->endTag( [ $Namespace => 'tables' ] );
d3422086	263
1e3867bf	264	#
	265	# Views
	266	#
87c5565e	267	xml_obj_children( $xml, $schema,
	268	tag => 'view',
	269	methods => [qw/name sql fields order/],
	270	);
d3422086	271
1e3867bf	272	#
	273	# Tiggers
	274	#
87c5565e	275	xml_obj_children( $xml, $schema,
87c5565e	276	tag => 'trigger',
d3422086	277	methods => [qw/name database_event action on_table perform_action_when
87c5565e	278	fields order/],
87c5565e	279	);
0a689100	280
1e3867bf	281	#
	282	# Procedures
	283	#
87c5565e	284	xml_obj_children( $xml, $schema,
	285	tag => 'procedure',
	286	methods => [qw/name sql parameters owner comments order/],
	287	);
d3422086	288
0a689100	289	$xml->endTag([ $Namespace => 'schema' ]);
	290	$xml->end;
	291
	292	return $io;
	293	}
	294
87c5565e	295
	296	#
	297	# Takes and XML::Write object, Schema::* parent object, the tag name,
	298	# the collection name and a list of methods (of the children) to write as XML.
	299	# The collection name defaults to the name with an s on the end and is used to
	300	# work out the method to get the children with. eg a name of 'foo' gives a
	301	# collection of foos and gets the members using ->get_foos.
	302	#
	303	sub xml_obj_children {
	304	my ($xml,$parent) = (shift,shift);
	305	my %args = @_;
	306	my ($name,$collection_name,$methods)
	307	= @args{qw/tag collection_tag methods/};
	308	$collection_name \|\|= "${name}s";
	309	my $meth = "get_$collection_name";
	310
	311	my @kids = $parent->$meth;
	312	#@kids \|\| return;
	313	$xml->startTag( [ $Namespace => $collection_name ] );
	314	for my $obj ( @kids ) {
	315	xml_obj($xml, $obj,
	316	tag => "$name",
	317	end_tag => 1,
	318	methods => $methods,
	319	);
	320	}
	321	$xml->endTag( [ $Namespace => $collection_name ] );
	322	}
	323
1caf2bb2	324	#
23735f6a	325	# Takes an XML::Writer, Schema::* object and list of method names
b89a67a0	326	# and writes the obect out as XML. All methods values are written as attributes
87c5565e	327	# except for the methods listed in @MAP_AS_ELEMENTS which get written as child
87c5565e	328	# data elements.
b89a67a0	329	#
23735f6a	330	# The attributes/tags are written in the same order as the method names are
b89a67a0	331	# passed.
	332	#
	333	# TODO
1caf2bb2	334	# - Should the Namespace be passed in instead of global? Pass in the same
	335	# as Writer ie [ NS => TAGNAME ]
	336	#
23735f6a	337	my $elements_re = join("\|", @MAP_AS_ELEMENTS);
23735f6a	338	$elements_re = qr/^($elements_re)$/;
0a689100	339	sub xml_obj {
d3422086	340	my ($xml, $obj, %args) = @_;
	341	my $tag = $args{'tag'} \|\| '';
	342	my $end_tag = $args{'end_tag'} \|\| '';
d3422086	343	my @meths = @{ $args{'methods'} };
	344	my $empty_tag = 0;
	345
b89a67a0	346	# Use array to ensure consistant (ie not hash) ordering of attribs
	347	# The order comes from the meths list passed in.
	348	my @tags;
	349	my @attr;
	350	foreach ( grep { defined $obj->$_ } @meths ) {
23735f6a	351	my $what = m/$elements_re/ ? \@tags : \@attr;
e0a0c3e1	352	my $val = $_ eq 'extra'
	353	? { $obj->$_ }
	354	: $obj->$_;
0a689100	355	$val = ref $val eq 'ARRAY' ? join(',', @$val) : $val;
b89a67a0	356	push @$what, $_ => $val;
	357	};
	358	my $child_tags = @tags;
	359	$end_tag && !$child_tags
	360	? $xml->emptyTag( [ $Namespace => $tag ], @attr )
	361	: $xml->startTag( [ $Namespace => $tag ], @attr );
	362	while ( my ($name,$val) = splice @tags,0,2 ) {
e0a0c3e1	363	if ( ref $val eq 'HASH' ) {
	364	$xml->emptyTag( [ $Namespace => $name ],
	365	map { ($_, $val->{$_}) } sort keys %$val );
	366	}
	367	else {
	368	$xml->dataElement( [ $Namespace => $name ], $val );
	369	}
0a689100	370	}
b89a67a0	371	$xml->endTag( [ $Namespace => $tag ] ) if $child_tags && $end_tag;
0a689100	372	}
	373
	374	1;
	375
	376	# -------------------------------------------------------------------
	377	# The eyes of fire, the nostrils of air,
	378	# The mouth of water, the beard of earth.
	379	# William Blake
	380	# -------------------------------------------------------------------
	381
	382	=pod
	383
	384	=head1 AUTHORS
	385
d3422086	386	Ken Y. Clark E<lt>kclark@cpan.orgE<gt>,
d3422086	387	Darren Chamberlain E<lt>darren@cpan.orgE<gt>,
0a689100	388	Mark Addison E<lt>mark.addison@itn.co.ukE<gt>.
	389
	390	=head1 SEE ALSO
	391
a7d50b44	392	perl(1), SQL::Translator, SQL::Translator::Parser::XML::SQLFairy,
0a689100	393	SQL::Translator::Schema, XML::Writer.
	394
	395	=cut