[dbsrgits/SQL-Translator.git] / lib / SQL / Translator / Schema.pm

package SQL::Translator::Schema;

# ----------------------------------------------------------------------
# $Id: Schema.pm,v 1.8 2003-06-18 23:14:31 kycl4rk Exp $
# ----------------------------------------------------------------------
# Copyright (C) 2003 Ken Y. Clark <kclark@cpan.org>
#
# 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::Schema - SQL::Translator schema object

=head1 SYNOPSIS

  use SQL::Translator::Schema;
  my $schema = SQL::Translator::Schema->new;
  my $table  = $schema->add_table( name => 'foo' );
  my $view   = $schema->add_view( name => 'bar', sql => '...' );

=head1 DESCSIPTION

C<SQL::Translator::Schema> is the object that accepts, validates, and
returns the database structure.

=head1 METHODS

=cut

use strict;
use Class::Base;
use SQL::Translator::Schema::Constants;
use SQL::Translator::Schema::Table;
use SQL::Translator::Utils 'parse_list_arg';
use SQL::Translator::Schema::View;

use base 'Class::Base';
use vars qw[ $VERSION $TABLE_ORDER $VIEW_ORDER ];

$VERSION = sprintf "%d.%02d", q$Revision: 1.8 $ =~ /(\d+)\.(\d+)/;

# ----------------------------------------------------------------------
sub init {

=pod

=head2 new

Object constructor.

  my $schema   =  SQL::Translator->new(
      name     => 'Foo',
      database => 'MySQL',
  );

=cut

    my ( $self, $config ) = @_;
    $self->params( $config, qw[ name database ] ) || return undef;
    return $self;
}

# ----------------------------------------------------------------------
sub add_table {

=pod

=head2 add_table

Add a table object.  Returns the new SQL::Translator::Schema::Table object.
The "name" parameter is required.  If you try to create a table with the
same name as an existing table, you will get an error and the table will 
not be created.

  my $t1 = $schema->add_table( name => 'foo' ) or die $schema->error;
  my $t2 = SQL::Translator::Schema::Table->new( name => 'bar' );
  $t2    = $schema->add_table( $table_bar ) or die $schema->error;

=cut

    my $self        = shift;
    my $table_class = 'SQL::Translator::Schema::Table';
    my $table;

    if ( UNIVERSAL::isa( $_[0], $table_class ) ) {
        $table = shift;
        $table->schema( $self );
    }
    else {
        my %args = @_;
        $args{'schema'} = $self;
        $table = $table_class->new( \%args ) or return 
            $self->error( $table_class->error );
    }

    $table->order( ++$TABLE_ORDER );
    my $table_name = $table->name or return $self->error('No table name');

    if ( defined $self->{'tables'}{ $table_name } ) {
        return $self->error(qq[Can't create table: "$table_name" exists]);
    }
    else {
        $self->{'tables'}{ $table_name } = $table;
    }

    return $table;
}

# ----------------------------------------------------------------------
sub add_view {

=pod

=head2 add_view

Add a view object.  Returns the new SQL::Translator::Schema::View object.
The "name" parameter is required.  If you try to create a view with the
same name as an existing view, you will get an error and the view will 
not be created.

  my $v1 = $schema->add_view( name => 'foo' );
  my $v2 = SQL::Translator::Schema::View->new( name => 'bar' );
  $v2    = $schema->add_view( $view_bar ) or die $schema->error;

=cut

    my $self        = shift;
    my $view_class = 'SQL::Translator::Schema::View';
    my $view;

    if ( UNIVERSAL::isa( $_[0], $view_class ) ) {
        $view = shift;
    }
    else {
        my %args = @_;
        return $self->error('No view name') unless $args{'name'};
        $view = $view_class->new( \%args ) or return $view_class->error;
    }

    $view->order( ++$VIEW_ORDER );
    my $view_name = $view->name or return $self->error('No view name');

    if ( defined $self->{'views'}{ $view_name } ) { 
        return $self->error(qq[Can't create view: "$view_name" exists]);
    }
    else {
        $self->{'views'}{ $view_name } = $view;
    }

    return $view;
}

# ----------------------------------------------------------------------
sub database {

=pod

=head2 database

Get or set the schema's database.  (optional)

  my $database = $schema->database('PostgreSQL');

=cut

    my $self = shift;
    $self->{'database'} = shift if @_;
    return $self->{'database'} || '';
}

# ----------------------------------------------------------------------
sub is_valid {

=pod

=head2 is_valid

Returns true if all the tables and views are valid.

  my $ok = $schema->is_valid or die $schema->error;

=cut

    my $self = shift;

    return $self->error('No tables') unless $self->get_tables;

    for my $object ( $self->get_tables, $self->get_views ) {
        return $object->error unless $object->is_valid;
    }

    return 1;
}

# ----------------------------------------------------------------------
sub get_table {

=pod

=head2 get_table

Returns a table by the name provided.

  my $table = $schema->get_table('foo');

=cut

    my $self       = shift;
    my $table_name = shift or return $self->error('No table name');
    return $self->error( qq[Table "$table_name" does not exist] ) unless
        exists $self->{'tables'}{ $table_name };
    return $self->{'tables'}{ $table_name };
}

# ----------------------------------------------------------------------
sub get_tables {

=pod

=head2 get_tables

Returns all the tables as an array or array reference.

  my @tables = $schema->get_tables;

=cut

    my $self   = shift;
    my @tables = 
        map  { $_->[1] } 
        sort { $a->[0] <=> $b->[0] } 
        map  { [ $_->order, $_ ] }
        values %{ $self->{'tables'} };

    if ( @tables ) {
        return wantarray ? @tables : \@tables;
    }
    else {
        $self->error('No tables');
        return wantarray ? () : undef;
    }
}

# ----------------------------------------------------------------------
sub get_view {

=pod

=head2 get_view

Returns a view by the name provided.

  my $view = $schema->get_view('foo');

=cut

    my $self      = shift;
    my $view_name = shift or return $self->error('No view name');
    return $self->error('View "$view_name" does not exist') unless
        exists $self->{'views'}{ $view_name };
    return $self->{'views'}{ $view_name };
}

# ----------------------------------------------------------------------
sub get_views {

=pod

=head2 get_views

Returns all the views as an array or array reference.

  my @views = $schema->get_views;

=cut

    my $self  = shift;
    my @views = 
        map  { $_->[1] } 
        sort { $a->[0] <=> $b->[0] } 
        map  { [ $_->order, $_ ] }
        values %{ $self->{'views'} };

    if ( @views ) {
        return wantarray ? @views : \@views;
    }
    else {
        $self->error('No views');
        return wantarray ? () : undef;
    }
}

# ----------------------------------------------------------------------
sub make_natural_joins {

=pod

=head2 make_natural_joins

Creates foriegn key relationships among like-named fields in different
tables.  Accepts the following arguments:

=over 4

=item * join_pk_only 

A True or False argument which determins whether or not to perform 
the joins from primary keys to fields of the same name in other tables

=item * skip_fields

A list of fields to skip in the joins

=back 4

  $schema->make_natural_joins(
      join_pk_only => 1,
      skip_fields  => 'name,department_id',
  );

=cut

    my $self         = shift;
    my %args         = @_;
    my $join_pk_only = $args{'join_pk_only'} || 0;
    my %skip_fields  = map { s/^\s+|\s+$//g; $_, 1 } @{ 
        parse_list_arg( $args{'skip_fields'} ) 
    };

    my ( %common_keys, %pk );
    for my $table ( $self->get_tables ) {
        for my $field ( $table->get_fields ) {
            my $field_name = $field->name or next;
            next if $skip_fields{ $field_name };
            $pk{ $field_name } = 1 if $field->is_primary_key;
            push @{ $common_keys{ $field_name } }, $table->name;
        }
    } 
   
    for my $field ( keys %common_keys ) {
        next if $join_pk_only and !defined $pk{ $field };

        my @table_names = @{ $common_keys{ $field } };
        next unless scalar @table_names > 1;

        for my $i ( 0 .. $#table_names ) {
            my $table1 = $self->get_table( $table_names[ $i ] ) or next;

            for my $j ( 1 .. $#table_names ) {
                my $table2 = $self->get_table( $table_names[ $j ] ) or next;
                next if $table1->name eq $table2->name;

                $table1->add_constraint(
                    type             => FOREIGN_KEY,
                    fields           => $field,
                    reference_table  => $table2->name,
                    reference_fields => $field,
                );
            }               
        }
    } 

    return 1;
}

# ----------------------------------------------------------------------
sub name {

=pod

=head2 name

Get or set the schema's name.  (optional)

  my $schema_name = $schema->name('Foo Database');

=cut

    my $self = shift;
    $self->{'name'} = shift if @_;
    return $self->{'name'} || '';
}

# ----------------------------------------------------------------------
sub DESTROY {
    my $self = shift;
    undef $_ for values %{ $self->{'tables'} };
    undef $_ for values %{ $self->{'views'}  };
}

1;

# ----------------------------------------------------------------------

=pod

=head1 AUTHOR

Ken Y. Clark E<lt>kclark@cpan.orgE<gt>

=cut
Commit	Line	Data
3c5de62a	1	package SQL::Translator::Schema;
	2
	3	# ----------------------------------------------------------------------
9bfce1c2	4	# $Id: Schema.pm,v 1.8 2003-06-18 23:14:31 kycl4rk Exp $
3c5de62a	5	# ----------------------------------------------------------------------
	6	# Copyright (C) 2003 Ken Y. Clark <kclark@cpan.org>
	7	#
	8	# This program is free software; you can redistribute it and/or
	9	# modify it under the terms of the GNU General Public License as
	10	# published by the Free Software Foundation; version 2.
	11	#
	12	# This program is distributed in the hope that it will be useful, but
	13	# WITHOUT ANY WARRANTY; without even the implied warranty of
	14	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	# General Public License for more details.
	16	#
	17	# You should have received a copy of the GNU General Public License
	18	# along with this program; if not, write to the Free Software
	19	# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	20	# 02111-1307 USA
	21	# -------------------------------------------------------------------
	22
	23	=pod
	24
	25	=head1 NAME
	26
	27	SQL::Translator::Schema - SQL::Translator schema object
	28
	29	=head1 SYNOPSIS
	30
	31	use SQL::Translator::Schema;
76dce619	32	my $schema = SQL::Translator::Schema->new;
	33	my $table = $schema->add_table( name => 'foo' );
	34	my $view = $schema->add_view( name => 'bar', sql => '...' );
3c5de62a	35
	36	=head1 DESCSIPTION
	37
	38	C<SQL::Translator::Schema> is the object that accepts, validates, and
	39	returns the database structure.
	40
	41	=head1 METHODS
	42
	43	=cut
	44
	45	use strict;
	46	use Class::Base;
9480e70b	47	use SQL::Translator::Schema::Constants;
3c5de62a	48	use SQL::Translator::Schema::Table;
40c522c6	49	use SQL::Translator::Utils 'parse_list_arg';
3c5de62a	50	use SQL::Translator::Schema::View;
	51
	52	use base 'Class::Base';
76dce619	53	use vars qw[ $VERSION $TABLE_ORDER $VIEW_ORDER ];
3c5de62a	54
9bfce1c2	55	$VERSION = sprintf "%d.%02d", q$Revision: 1.8 $ =~ /(\d+)\.(\d+)/;
3c5de62a	56
	57	# ----------------------------------------------------------------------
	58	sub init {
	59
	60	=pod
	61
	62	=head2 new
	63
	64	Object constructor.
	65
99248301	66	my $schema = SQL::Translator->new(
	67	name => 'Foo',
	68	database => 'MySQL',
	69	);
3c5de62a	70
	71	=cut
	72
	73	my ( $self, $config ) = @_;
99248301	74	$self->params( $config, qw[ name database ] ) \|\| return undef;
3c5de62a	75	return $self;
	76	}
	77
	78	# ----------------------------------------------------------------------
76dce619	79	sub add_table {
3c5de62a	80
	81	=pod
	82
76dce619	83	=head2 add_table
3c5de62a	84
76dce619	85	Add a table object. Returns the new SQL::Translator::Schema::Table object.
99248301	86	The "name" parameter is required. If you try to create a table with the
	87	same name as an existing table, you will get an error and the table will
	88	not be created.
3c5de62a	89
68e8e2e1	90	my $t1 = $schema->add_table( name => 'foo' ) or die $schema->error;
	91	my $t2 = SQL::Translator::Schema::Table->new( name => 'bar' );
	92	$t2 = $schema->add_table( $table_bar ) or die $schema->error;
3c5de62a	93
	94	=cut
	95
99248301	96	my $self = shift;
	97	my $table_class = 'SQL::Translator::Schema::Table';
	98	my $table;
	99
	100	if ( UNIVERSAL::isa( $_[0], $table_class ) ) {
	101	$table = shift;
	102	$table->schema( $self );
	103	}
	104	else {
	105	my %args = @_;
	106	$args{'schema'} = $self;
	107	$table = $table_class->new( \%args ) or return
	108	$self->error( $table_class->error );
	109	}
3c5de62a	110
d0b43695	111	$table->order( ++$TABLE_ORDER );
99248301	112	my $table_name = $table->name or return $self->error('No table name');
	113
	114	if ( defined $self->{'tables'}{ $table_name } ) {
	115	return $self->error(qq[Can't create table: "$table_name" exists]);
	116	}
	117	else {
	118	$self->{'tables'}{ $table_name } = $table;
99248301	119	}
3c5de62a	120
	121	return $table;
	122	}
	123
	124	# ----------------------------------------------------------------------
76dce619	125	sub add_view {
3c5de62a	126
	127	=pod
	128
76dce619	129	=head2 add_view
3c5de62a	130
76dce619	131	Add a view object. Returns the new SQL::Translator::Schema::View object.
99248301	132	The "name" parameter is required. If you try to create a view with the
	133	same name as an existing view, you will get an error and the view will
	134	not be created.
	135
68e8e2e1	136	my $v1 = $schema->add_view( name => 'foo' );
	137	my $v2 = SQL::Translator::Schema::View->new( name => 'bar' );
	138	$v2 = $schema->add_view( $view_bar ) or die $schema->error;
3c5de62a	139
	140	=cut
	141
99248301	142	my $self = shift;
	143	my $view_class = 'SQL::Translator::Schema::View';
	144	my $view;
	145
	146	if ( UNIVERSAL::isa( $_[0], $view_class ) ) {
	147	$view = shift;
	148	}
	149	else {
	150	my %args = @_;
	151	return $self->error('No view name') unless $args{'name'};
	152	$view = $view_class->new( \%args ) or return $view_class->error;
	153	}
3c5de62a	154
d0b43695	155	$view->order( ++$VIEW_ORDER );
99248301	156	my $view_name = $view->name or return $self->error('No view name');
	157
	158	if ( defined $self->{'views'}{ $view_name } ) {
	159	return $self->error(qq[Can't create view: "$view_name" exists]);
	160	}
	161	else {
	162	$self->{'views'}{ $view_name } = $view;
99248301	163	}
3c5de62a	164
76dce619	165	return $view;
3c5de62a	166	}
	167
	168	# ----------------------------------------------------------------------
99248301	169	sub database {
	170
	171	=pod
	172
	173	=head2 database
	174
	175	Get or set the schema's database. (optional)
	176
	177	my $database = $schema->database('PostgreSQL');
	178
	179	=cut
	180
	181	my $self = shift;
	182	$self->{'database'} = shift if @_;
	183	return $self->{'database'} \|\| '';
	184	}
	185
	186	# ----------------------------------------------------------------------
76dce619	187	sub is_valid {
3c5de62a	188
	189	=pod
	190
76dce619	191	=head2 is_valid
3c5de62a	192
76dce619	193	Returns true if all the tables and views are valid.
3c5de62a	194
76dce619	195	my $ok = $schema->is_valid or die $schema->error;
	196
	197	=cut
	198
	199	my $self = shift;
	200
	201	return $self->error('No tables') unless $self->get_tables;
	202
	203	for my $object ( $self->get_tables, $self->get_views ) {
	204	return $object->error unless $object->is_valid;
	205	}
	206
	207	return 1;
	208	}
	209
	210	# ----------------------------------------------------------------------
	211	sub get_table {
	212
	213	=pod
	214
	215	=head2 get_table
	216
	217	Returns a table by the name provided.
	218
	219	my $table = $schema->get_table('foo');
	220
	221	=cut
	222
	223	my $self = shift;
	224	my $table_name = shift or return $self->error('No table name');
99248301	225	return $self->error( qq[Table "$table_name" does not exist] ) unless
76dce619	226	exists $self->{'tables'}{ $table_name };
	227	return $self->{'tables'}{ $table_name };
	228	}
	229
	230	# ----------------------------------------------------------------------
	231	sub get_tables {
	232
	233	=pod
	234
	235	=head2 get_tables
	236
	237	Returns all the tables as an array or array reference.
	238
	239	my @tables = $schema->get_tables;
	240
	241	=cut
	242
	243	my $self = shift;
d0b43695	244	my @tables =
	245	map { $_->[1] }
	246	sort { $a->[0] <=> $b->[0] }
	247	map { [ $_->order, $_ ] }
76dce619	248	values %{ $self->{'tables'} };
	249
	250	if ( @tables ) {
	251	return wantarray ? @tables : \@tables;
	252	}
	253	else {
	254	$self->error('No tables');
	255	return wantarray ? () : undef;
	256	}
	257	}
	258
	259	# ----------------------------------------------------------------------
	260	sub get_view {
	261
	262	=pod
	263
	264	=head2 get_view
	265
	266	Returns a view by the name provided.
	267
	268	my $view = $schema->get_view('foo');
3c5de62a	269
	270	=cut
	271
	272	my $self = shift;
76dce619	273	my $view_name = shift or return $self->error('No view name');
	274	return $self->error('View "$view_name" does not exist') unless
	275	exists $self->{'views'}{ $view_name };
	276	return $self->{'views'}{ $view_name };
	277	}
3c5de62a	278
76dce619	279	# ----------------------------------------------------------------------
76dce619	280	sub get_views {
3c5de62a	281
76dce619	282	=pod
	283
	284	=head2 get_views
	285
	286	Returns all the views as an array or array reference.
	287
	288	my @views = $schema->get_views;
	289
	290	=cut
	291
	292	my $self = shift;
d0b43695	293	my @views =
	294	map { $_->[1] }
	295	sort { $a->[0] <=> $b->[0] }
	296	map { [ $_->order, $_ ] }
99248301	297	values %{ $self->{'views'} };
76dce619	298
	299	if ( @views ) {
	300	return wantarray ? @views : \@views;
	301	}
	302	else {
	303	$self->error('No views');
	304	return wantarray ? () : undef;
	305	}
3c5de62a	306	}
3c5de62a	307
99248301	308	# ----------------------------------------------------------------------
9480e70b	309	sub make_natural_joins {
	310
	311	=pod
	312
	313	=head2 make_natural_joins
	314
	315	Creates foriegn key relationships among like-named fields in different
	316	tables. Accepts the following arguments:
	317
	318	=over 4
	319
	320	=item * join_pk_only
	321
	322	A True or False argument which determins whether or not to perform
	323	the joins from primary keys to fields of the same name in other tables
	324
	325	=item * skip_fields
	326
	327	A list of fields to skip in the joins
	328
	329	=back 4
	330
	331	$schema->make_natural_joins(
	332	join_pk_only => 1,
	333	skip_fields => 'name,department_id',
	334	);
	335
	336	=cut
	337
	338	my $self = shift;
	339	my %args = @_;
	340	my $join_pk_only = $args{'join_pk_only'} \|\| 0;
40c522c6	341	my %skip_fields = map { s/^\s+\|\s+$//g; $_, 1 } @{
	342	parse_list_arg( $args{'skip_fields'} )
	343	};
9480e70b	344
	345	my ( %common_keys, %pk );
	346	for my $table ( $self->get_tables ) {
	347	for my $field ( $table->get_fields ) {
	348	my $field_name = $field->name or next;
	349	next if $skip_fields{ $field_name };
	350	$pk{ $field_name } = 1 if $field->is_primary_key;
	351	push @{ $common_keys{ $field_name } }, $table->name;
	352	}
	353	}
	354
	355	for my $field ( keys %common_keys ) {
	356	next if $join_pk_only and !defined $pk{ $field };
	357
	358	my @table_names = @{ $common_keys{ $field } };
	359	next unless scalar @table_names > 1;
	360
	361	for my $i ( 0 .. $#table_names ) {
	362	my $table1 = $self->get_table( $table_names[ $i ] ) or next;
	363
	364	for my $j ( 1 .. $#table_names ) {
	365	my $table2 = $self->get_table( $table_names[ $j ] ) or next;
	366	next if $table1->name eq $table2->name;
	367
	368	$table1->add_constraint(
	369	type => FOREIGN_KEY,
	370	fields => $field,
	371	reference_table => $table2->name,
	372	reference_fields => $field,
	373	);
	374	}
	375	}
	376	}
	377
	378	return 1;
	379	}
	380
	381	# ----------------------------------------------------------------------
99248301	382	sub name {
	383
	384	=pod
	385
	386	=head2 name
	387
	388	Get or set the schema's name. (optional)
	389
	390	my $schema_name = $schema->name('Foo Database');
	391
	392	=cut
	393
	394	my $self = shift;
	395	$self->{'name'} = shift if @_;
	396	return $self->{'name'} \|\| '';
	397	}
	398
d0b43695	399	# ----------------------------------------------------------------------
	400	sub DESTROY {
	401	my $self = shift;
	402	undef $_ for values %{ $self->{'tables'} };
	403	undef $_ for values %{ $self->{'views'} };
	404	}
	405
3c5de62a	406	1;
	407
	408	# ----------------------------------------------------------------------
	409
	410	=pod
	411
	412	=head1 AUTHOR
	413
	414	Ken Y. Clark E<lt>kclark@cpan.orgE<gt>
	415
	416	=cut