package SQL::Translator::Schema::Constraint;
# ----------------------------------------------------------------------
-# $Id: Constraint.pm,v 1.1 2003-05-01 04:24:59 kycl4rk Exp $
+# $Id: Constraint.pm,v 1.15 2004-11-05 13:19:31 grommit Exp $
# ----------------------------------------------------------------------
-# Copyright (C) 2003 Ken Y. Clark <kclark@cpan.org>
+# Copyright (C) 2002-4 SQLFairy Authors
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
my $constraint = SQL::Translator::Schema::Constraint->new(
name => 'foo',
fields => [ id ],
- type => 'primary_key',
+ type => PRIMARY_KEY,
);
=head1 DESCRIPTION
=cut
use strict;
-use Class::Base;
+use SQL::Translator::Schema::Constants;
+use SQL::Translator::Utils 'parse_list_arg';
+
+use base 'SQL::Translator::Schema::Object';
-use base 'Class::Base';
use vars qw($VERSION $TABLE_COUNT $VIEW_COUNT);
-$VERSION = 1.00;
+$VERSION = sprintf "%d.%02d", q$Revision: 1.15 $ =~ /(\d+)\.(\d+)/;
-use constant VALID_TYPE => {
- primary_key => 1,
- unique => 1,
- check => 1,
- foreign_key => 1,
-};
+my %VALID_CONSTRAINT_TYPE = (
+ PRIMARY_KEY, 1,
+ UNIQUE, 1,
+ CHECK_C, 1,
+ FOREIGN_KEY, 1,
+ NOT_NULL, 1,
+);
# ----------------------------------------------------------------------
-sub init {
+__PACKAGE__->_attributes( qw/
+ table name type fields reference_fields reference_table
+ match_type on_delete on_update expression deferrable
+/);
+
+# Override to remove empty arrays from args.
+# t/14postgres-parser breaks without this.
+sub init {
+
=pod
=head2 new
Object constructor.
my $schema = SQL::Translator::Schema::Constraint->new(
+ table => $table, # table to which it belongs
type => 'foreign_key', # type of table constraint
- name => 'fk_phone_id', # the name of the constraint
- fields => 'phone_id', # the field in the referring table
- reference_fields => 'phone_id', # the referenced table
- reference_table => 'phone', # the referenced fields
+ name => 'fk_phone_id', # name of the constraint
+ fields => 'phone_id', # field in the referring table
+ reference_fields => 'phone_id', # referenced field
+ reference_table => 'phone', # referenced table
match_type => 'full', # how to match
- on_delete_do => 'cascade', # what to do on deletes
- on_update_do => '', # what to do on updates
+ on_delete => 'cascade', # what to do on deletes
+ on_update => '', # what to do on updates
);
=cut
- my ( $self, $config ) = @_;
-# reference_fields reference_table
-# match_type on_delete_do on_update_do
- my @fields = qw[ name type fields ];
+ my $self = shift;
+ foreach ( values %{$_[0]} ) { $_ = undef if ref($_) eq "ARRAY" && ! @$_; }
+ $self->SUPER::init(@_);
+}
+
+# ----------------------------------------------------------------------
+sub deferrable {
+
+=pod
+
+=head2 deferrable
+
+Get or set whether the constraint is deferrable. If not defined,
+then returns "1." The argument is evaluated by Perl for True or
+False, so the following are eqivalent:
+
+ $deferrable = $field->deferrable(0);
+ $deferrable = $field->deferrable('');
+ $deferrable = $field->deferrable('0');
+
+=cut
+
+ my ( $self, $arg ) = @_;
+
+ if ( defined $arg ) {
+ $self->{'deferrable'} = $arg ? 1 : 0;
+ }
+
+ return defined $self->{'deferrable'} ? $self->{'deferrable'} : 1;
+}
+
+# ----------------------------------------------------------------------
+sub expression {
+
+=pod
+
+=head2 expression
+
+Gets and set the expression used in a CHECK constraint.
+
+ my $expression = $constraint->expression('...');
+
+=cut
- for my $arg ( @fields ) {
- next unless $config->{ $arg };
- $self->$arg( $config->{ $arg } ) or return;
+ my $self = shift;
+
+ if ( my $arg = shift ) {
+ # check arg here?
+ $self->{'expression'} = $arg;
}
- return $self;
+ return $self->{'expression'} || '';
+}
+
+# ----------------------------------------------------------------------
+sub is_valid {
+
+=pod
+
+=head2 is_valid
+
+Determine whether the constraint is valid or not.
+
+ my $ok = $constraint->is_valid;
+
+=cut
+
+ my $self = shift;
+ my $type = $self->type or return $self->error('No type');
+ my $table = $self->table or return $self->error('No table');
+ my @fields = $self->fields or return $self->error('No fields');
+ my $table_name = $table->name or return $self->error('No table name');
+
+ for my $f ( @fields ) {
+ next if $table->get_field( $f );
+ return $self->error(
+ "Constraint references non-existent field '$f' ",
+ "in table '$table_name'"
+ );
+ }
+
+ my $schema = $table->schema or return $self->error(
+ 'Table ', $table->name, ' has no schema object'
+ );
+
+ if ( $type eq FOREIGN_KEY ) {
+ return $self->error('Only one field allowed for foreign key')
+ if scalar @fields > 1;
+
+ my $ref_table_name = $self->reference_table or
+ return $self->error('No reference table');
+
+ my $ref_table = $schema->get_table( $ref_table_name ) or
+ return $self->error("No table named '$ref_table_name' in schema");
+
+ my @ref_fields = $self->reference_fields or return;
+
+ return $self->error('Only one field allowed for foreign key reference')
+ if scalar @ref_fields > 1;
+
+ for my $ref_field ( @ref_fields ) {
+ next if $ref_table->get_field( $ref_field );
+ return $self->error(
+ "Constraint from field(s) ",
+ join(', ', map {qq['$table_name.$_']} @fields),
+ " to non-existent field '$ref_table_name.$ref_field'"
+ );
+ }
+ }
+ elsif ( $type eq CHECK_C ) {
+ return $self->error('No expression for CHECK') unless
+ $self->expression;
+ }
+
+ return 1;
}
# ----------------------------------------------------------------------
=head2 fields
-Gets and set the fields the constraint is on. Accepts a list or arrayref,
-return both, too.
+Gets and set the fields the constraint is on. Accepts a string, list or
+arrayref; returns an array or array reference. Will unique the field
+names and keep them in order by the first occurrence of a field name.
+
+The fields are returned as Field objects if they exist or as plain
+names if not. (If you just want the names and want to avoid the Field's overload
+magic use L<field_names>).
+
+Returns undef or an empty list if the constraint has no fields set.
- my @fields = $constraint->fields( 'id' );
+ $constraint->fields('id');
+ $constraint->fields('id', 'name');
+ $constraint->fields( 'id, name' );
+ $constraint->fields( [ 'id', 'name' ] );
+ $constraint->fields( qw[ id name ] );
+
+ my @fields = $constraint->fields;
=cut
my $self = shift;
- my $fields = ref $_[0] eq 'ARRAY' ? shift : [ @_ ];
+ my $fields = parse_list_arg( @_ );
if ( @$fields ) {
- $self->{'fields'} = $fields;
+ my ( %unique, @unique );
+ for my $f ( @$fields ) {
+ next if $unique{ $f };
+ $unique{ $f } = 1;
+ push @unique, $f;
+ }
+
+ $self->{'fields'} = \@unique;
}
- return wantarray ? @{ $self->{'fields'} || [] } : $self->{'fields'};
+ if ( @{ $self->{'fields'} || [] } ) {
+ # We have to return fields that don't exist on the table as names in
+ # case those fields havn't been created yet.
+ my @ret = map {
+ $self->table->get_field($_) || $_ } @{ $self->{'fields'} };
+ return wantarray ? @ret : \@ret;
+ }
+ else {
+ return wantarray ? () : undef;
+ }
+}
+
+# ----------------------------------------------------------------------
+sub field_names {
+
+=head2 field_names
+
+Read-only method to return a list or array ref of the field names. Returns undef
+or an empty list if the constraint has no fields set. Usefull if you want to
+avoid the overload magic of the Field objects returned by the fields method.
+
+ my @names = $constraint->field_names;
+
+=cut
+
+ my $self = shift;
+ return wantarray ? @{ $self->{'fields'} } : $self->{'fields'};
+}
+
+# ----------------------------------------------------------------------
+sub match_type {
+
+=pod
+
+=head2 match_type
+
+Get or set the constraint's match_type. Only valid values are "full"
+or "partial."
+
+ my $match_type = $constraint->match_type('FULL');
+
+=cut
+
+ my $self = shift;
+
+ if ( my $arg = lc shift ) {
+ return $self->error("Invalid match type: $arg")
+ unless $arg eq 'full' || $arg eq 'partial';
+ $self->{'match_type'} = $arg;
+ }
+
+ return $self->{'match_type'} || '';
}
# ----------------------------------------------------------------------
=cut
my $self = shift;
- $self->{'name'} = shift if @_;
+ my $arg = shift || '';
+ $self->{'name'} = $arg if $arg;
return $self->{'name'} || '';
}
# ----------------------------------------------------------------------
-sub type {
+sub options {
=pod
-=head2 type
+=head2 options
-Get or set the constraint's type.
+Gets or adds to the constraints's options (e.g., "INITIALLY IMMEDIATE").
+Returns an array or array reference.
+
+ $constraint->options('NORELY');
+ my @options = $constraint->options;
+
+=cut
- my $type = $constraint->type('primary_key');
+ my $self = shift;
+ my $options = parse_list_arg( @_ );
+
+ push @{ $self->{'options'} }, @$options;
+
+ if ( ref $self->{'options'} ) {
+ return wantarray ? @{ $self->{'options'} || [] } : $self->{'options'};
+ }
+ else {
+ return wantarray ? () : [];
+ }
+}
+
+
+# ----------------------------------------------------------------------
+sub on_delete {
+
+=pod
+
+=head2 on_delete
+
+Get or set the constraint's "on delete" action.
+
+ my $action = $constraint->on_delete('cascade');
=cut
my $self = shift;
+
+ if ( my $arg = shift ) {
+ # validate $arg?
+ $self->{'on_delete'} = $arg;
+ }
- if ( my $type = shift ) {
- return $self->error("Invalid constraint type: $type")
- unless VALID_TYPE->{ $type };
- $self->{'type'} = $type;
+ return $self->{'on_delete'} || '';
+}
+
+# ----------------------------------------------------------------------
+sub on_update {
+
+=pod
+
+=head2 on_update
+
+Get or set the constraint's "on update" action.
+
+ my $action = $constraint->on_update('no action');
+
+=cut
+
+ my $self = shift;
+
+ if ( my $arg = shift ) {
+ # validate $arg?
+ $self->{'on_update'} = $arg;
}
- return $self->{'type'} || '';
+ return $self->{'on_update'} || '';
}
+# ----------------------------------------------------------------------
+sub reference_fields {
+
+=pod
+
+=head2 reference_fields
+
+Gets and set the fields in the referred table. Accepts a string, list or
+arrayref; returns an array or array reference.
+
+ $constraint->reference_fields('id');
+ $constraint->reference_fields('id', 'name');
+ $constraint->reference_fields( 'id, name' );
+ $constraint->reference_fields( [ 'id', 'name' ] );
+ $constraint->reference_fields( qw[ id name ] );
+
+ my @reference_fields = $constraint->reference_fields;
+
+=cut
+
+ my $self = shift;
+ my $fields = parse_list_arg( @_ );
+
+ if ( @$fields ) {
+ $self->{'reference_fields'} = $fields;
+ }
+
+ # Nothing set so try and derive it from the other constraint data
+ unless ( ref $self->{'reference_fields'} ) {
+ my $table = $self->table or return $self->error('No table');
+ my $schema = $table->schema or return $self->error('No schema');
+ if ( my $ref_table_name = $self->reference_table ) {
+ my $ref_table = $schema->get_table( $ref_table_name ) or
+ return $self->error("Can't find table '$ref_table_name'");
+
+ if ( my $constraint = $ref_table->primary_key ) {
+ $self->{'reference_fields'} = [ $constraint->fields ];
+ }
+ else {
+ $self->error(
+ 'No reference fields defined and cannot find primary key in ',
+ "reference table '$ref_table_name'"
+ );
+ }
+ }
+ # No ref table so we are not that sort of constraint, hence no ref
+ # fields. So we let the return below return an empty list.
+ }
+
+ if ( ref $self->{'reference_fields'} ) {
+ return wantarray
+ ? @{ $self->{'reference_fields'} }
+ : $self->{'reference_fields'};
+ }
+ else {
+ return wantarray ? () : [];
+ }
+}
# ----------------------------------------------------------------------
-sub is_valid {
+sub reference_table {
=pod
-=head2 is_valid
+=head2 reference_table
-Determine whether the constraint is valid or not.
+Get or set the table referred to by the constraint.
- my $ok = $constraint->is_valid;
+ my $reference_table = $constraint->reference_table('foo');
=cut
my $self = shift;
- return ( $self->name && $self->{'type'} && @{ $self->fields } ) ? 1 : 0;
+ $self->{'reference_table'} = shift if @_;
+ return $self->{'reference_table'} || '';
+}
+
+# ----------------------------------------------------------------------
+sub table {
+
+=pod
+
+=head2 table
+
+Get or set the constraint's table object.
+
+ my $table = $field->table;
+
+=cut
+
+ my $self = shift;
+ if ( my $arg = shift ) {
+ return $self->error('Not a table object') unless
+ UNIVERSAL::isa( $arg, 'SQL::Translator::Schema::Table' );
+ $self->{'table'} = $arg;
+ }
+
+ return $self->{'table'};
+}
+
+# ----------------------------------------------------------------------
+sub type {
+
+=pod
+
+=head2 type
+
+Get or set the constraint's type.
+
+ my $type = $constraint->type( PRIMARY_KEY );
+
+=cut
+
+ my $self = shift;
+
+ if ( my $type = uc shift ) {
+ $type =~ s/_/ /g;
+ return $self->error("Invalid constraint type: $type")
+ unless $VALID_CONSTRAINT_TYPE{ $type };
+ $self->{'type'} = $type;
+ }
+
+ return $self->{'type'} || '';
+}
+# ----------------------------------------------------------------------
+sub DESTROY {
+ my $self = shift;
+ undef $self->{'table'}; # destroy cyclical reference
}
1;
=head1 AUTHOR
-Ken Y. Clark E<lt>kclark@cpan.orgE<gt>
+Ken Y. Clark E<lt>kclark@cpan.orgE<gt>.
=cut