1 package DBIx::Class::Storage::DBI::Replication;
6 use DBIx::Class::Storage::DBI;
8 use base qw/Class::Accessor::Fast/;
10 __PACKAGE__->mk_accessors( qw/read_source write_source/ );
14 DBIx::Class::Storage::DBI::Replication - Replicated database support
18 # change storage_type in your schema class
19 $schema->storage_type( '::DBI::Replication' );
20 $schema->connect_info( [
21 [ "dbi:mysql:database=test;hostname=master", "username", "password", { AutoCommit => 1 } ], # master
22 [ "dbi:mysql:database=test;hostname=slave1", "username", "password", { priority => 10 } ], # slave1
23 [ "dbi:mysql:database=test;hostname=slave2", "username", "password", { priority => 10 } ], # slave2
26 # If you use LIMIT in your queries (effectively, if you use SQL::Abstract::Limit),
27 # do not forget to set up limit_dialect (see: perldoc SQL::Abstract::Limit)
28 # DBIC can not set it up automatically, since DBD::Multi could not be supported directly
29 $schema->limit_dialect( 'LimitXY' ) # For MySQL
33 This class implements replicated data store for DBI. Currently you can define one master and numerous slave database
34 connections. All write-type queries (INSERT, UPDATE, DELETE and even LAST_INSERT_ID) are routed to master database,
35 all read-type queries (SELECTs) go to the slave database.
37 For every slave database you can define a priority value, which controls data source usage pattern. It uses
38 L<DBD::Multi>, so first the lower priority data sources used (if they have the same priority, the are used
39 randomized), than if all low priority data sources fail, higher ones tried in order.
45 my $class = ref( $proto ) || $proto;
48 bless( $self, $class );
50 $self->write_source( DBIx::Class::Storage::DBI->new );
51 $self->read_source( DBIx::Class::Storage::DBI->new );
59 my @sources = ($self->read_source, $self->write_source);
61 return wantarray ? @sources : \@sources;
65 my( $self, $source_info ) = @_;
67 $self->write_source->connect_info( $source_info->[0] );
69 my @dsns = map { ($_->[3]->{priority} || 10) => $_ } @{$source_info}[1..@$source_info-1];
70 $self->read_source->connect_info( [ 'dbi:Multi:', undef, undef, { dsns => \@dsns } ] );
74 shift->read_source->select( @_ );
77 shift->read_source->select_single( @_ );
80 shift->read_source->throw_exception( @_ );
83 shift->read_source->sql_maker( @_ );
85 sub columns_info_for {
86 shift->read_source->columns_info_for( @_ );
89 shift->read_source->sqlt_type( @_ );
92 shift->read_source->create_ddl_dir( @_ );
94 sub deployment_statements {
95 shift->read_source->deployment_statements( @_ );
98 shift->read_source->datetime_parser( @_ );
100 sub datetime_parser_type {
101 shift->read_source->datetime_parser_type( @_ );
103 sub build_datetime_parser {
104 shift->read_source->build_datetime_parser( @_ );
109 $self->$_->limit_dialect( @_ ) for( $self->all_sources );
113 $self->$_->quote_char( @_ ) for( $self->all_sources );
117 $self->$_->quote_char( @_ ) for( $self->all_sources );
121 $self->$_->disconnect( @_ ) for( $self->all_sources );
126 undef $self->{write_source};
127 undef $self->{read_sources};
131 shift->write_source->last_insert_id( @_ );
134 shift->write_source->insert( @_ );
137 shift->write_source->update( @_ );
140 shift->write_source->update_all( @_ );
143 shift->write_source->delete( @_ );
146 shift->write_source->delete_all( @_ );
149 shift->write_source->create( @_ );
152 shift->write_source->find_or_create( @_ );
154 sub update_or_create {
155 shift->write_source->update_or_create( @_ );
158 shift->write_source->connected( @_ );
160 sub ensure_connected {
161 shift->write_source->ensure_connected( @_ );
164 shift->write_source->dbh( @_ );
167 shift->write_source->txn_begin( @_ );
170 shift->write_source->txn_commit( @_ );
173 shift->write_source->txn_rollback( @_ );
176 shift->write_source->sth( @_ );
179 shift->write_source->deploy( @_ );
183 sub debugfh { shift->_not_supported( 'debugfh' ) };
184 sub debugcb { shift->_not_supported( 'debugcb' ) };
187 my( $self, $method ) = @_;
189 die "This Storage does not support $method method.";
194 L<DBI::Class::Storage::DBI>, L<DBD::Multi>, L<DBI>
198 Norbert Csongrádi <bert@cpan.org>
200 Peter Siklósi <einon@einon.hu>
204 You may distribute this code under the same terms as Perl itself.