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
25 { limit_dialect => 'LimitXY' } # If needed, see below
30 This class implements replicated data store for DBI. Currently you can define one master and numerous slave database
31 connections. All write-type queries (INSERT, UPDATE, DELETE and even LAST_INSERT_ID) are routed to master database,
32 all read-type queries (SELECTs) go to the slave database.
34 For every slave database you can define a priority value, which controls data source usage pattern. It uses
35 L<DBD::Multi>, so first the lower priority data sources used (if they have the same priority, the are used
36 randomized), than if all low priority data sources fail, higher ones tried in order.
42 If you use LIMIT in your queries (effectively, if you use SQL::Abstract::Limit), do not forget to set up limit_dialect (perldoc SQL::Abstract::Limit) by passing it as an option in the (optional) hash reference to connect_info.
43 DBIC can not set it up automatically, since it can not guess DBD::Multi connection types.
49 my $class = ref( $proto ) || $proto;
52 bless( $self, $class );
54 $self->write_source( DBIx::Class::Storage::DBI->new );
55 $self->read_source( DBIx::Class::Storage::DBI->new );
63 my @sources = ($self->read_source, $self->write_source);
65 return wantarray ? @sources : \@sources;
69 my( $self, $source_info ) = @_;
71 my( $info, $global_options, $options, @dsns );
73 $info = [ @$source_info ];
75 $global_options = ref $info->[-1] eq 'HASH' ? pop( @$info ) : {};
76 if( ref( $options = $info->[0]->[-1] ) eq 'HASH' ) {
77 # Local options present in dsn, merge them with global options
78 map { $global_options->{$_} = $options->{$_} } keys %$options;
82 # We need to copy-pass $global_options, since connect_info clears it while processing options
83 $self->write_source->connect_info( [ @{$info->[0]}, { %$global_options } ] );
85 @dsns = map { ($_->[3]->{priority} || 10) => $_ } @{$info}[1..@$info-1];
86 $global_options->{dsns} = \@dsns;
88 $self->read_source->connect_info( [ 'dbi:Multi:', undef, undef, { %$global_options } ] );
92 shift->read_source->select( @_ );
95 shift->read_source->select_single( @_ );
98 shift->read_source->throw_exception( @_ );
101 shift->read_source->sql_maker( @_ );
103 sub columns_info_for {
104 shift->read_source->columns_info_for( @_ );
107 shift->read_source->sqlt_type( @_ );
110 shift->read_source->create_ddl_dir( @_ );
112 sub deployment_statements {
113 shift->read_source->deployment_statements( @_ );
115 sub datetime_parser {
116 shift->read_source->datetime_parser( @_ );
118 sub datetime_parser_type {
119 shift->read_source->datetime_parser_type( @_ );
121 sub build_datetime_parser {
122 shift->read_source->build_datetime_parser( @_ );
127 $self->$_->limit_dialect( @_ ) for( $self->all_sources );
131 $self->$_->quote_char( @_ ) for( $self->all_sources );
135 $self->$_->quote_char( @_ ) for( $self->all_sources );
139 $self->$_->disconnect( @_ ) for( $self->all_sources );
144 undef $self->{write_source};
145 undef $self->{read_sources};
149 shift->write_source->last_insert_id( @_ );
152 shift->write_source->insert( @_ );
155 shift->write_source->update( @_ );
158 shift->write_source->update_all( @_ );
161 shift->write_source->delete( @_ );
164 shift->write_source->delete_all( @_ );
167 shift->write_source->create( @_ );
170 shift->write_source->find_or_create( @_ );
172 sub update_or_create {
173 shift->write_source->update_or_create( @_ );
176 shift->write_source->connected( @_ );
178 sub ensure_connected {
179 shift->write_source->ensure_connected( @_ );
182 shift->write_source->dbh( @_ );
185 shift->write_source->txn_begin( @_ );
188 shift->write_source->txn_commit( @_ );
191 shift->write_source->txn_rollback( @_ );
194 shift->write_source->sth( @_ );
197 shift->write_source->deploy( @_ );
201 sub debugfh { shift->_not_supported( 'debugfh' ) };
202 sub debugcb { shift->_not_supported( 'debugcb' ) };
205 my( $self, $method ) = @_;
207 die "This Storage does not support $method method.";
212 L<DBI::Class::Storage::DBI>, L<DBD::Multi>, L<DBI>
216 Norbert Csongrádi <bert@cpan.org>
218 Peter Siklósi <einon@einon.hu>
222 You may distribute this code under the same terms as Perl itself.