Commit | Line | Data |
f5d3a5de |
1 | package DBIx::Class::Storage::DBI::Replication; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | |
6 | use DBIx::Class::Storage::DBI; |
7 | use DBD::Multi; |
8 | use base qw/Class::Accessor::Fast/; |
9 | |
10 | __PACKAGE__->mk_accessors( qw/read_source write_source/ ); |
11 | |
12 | =head1 NAME |
13 | |
14 | DBIx::Class::Storage::DBI::Replication - EXPERIMENTAL Replicated database support |
15 | |
16 | =head1 SYNOPSIS |
17 | |
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 |
24 | <...>, |
25 | { limit_dialect => 'LimitXY' } # If needed, see below |
26 | ] ); |
27 | |
28 | =head1 DESCRIPTION |
29 | |
30 | Warning: This class is marked EXPERIMENTAL. It works for the authors but does |
31 | not currently have automated tests so your mileage may vary. |
32 | |
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. |
36 | |
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. |
40 | |
41 | =head1 CONFIGURATION |
42 | |
43 | =head2 Limit dialect |
44 | |
45 | 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. |
46 | DBIC can not set it up automatically, since it can not guess DBD::Multi connection types. |
47 | |
48 | =cut |
49 | |
50 | sub new { |
51 | my $proto = shift; |
52 | my $class = ref( $proto ) || $proto; |
53 | my $self = {}; |
54 | |
55 | bless( $self, $class ); |
56 | |
57 | $self->write_source( DBIx::Class::Storage::DBI->new ); |
58 | $self->read_source( DBIx::Class::Storage::DBI->new ); |
59 | |
60 | return $self; |
61 | } |
62 | |
63 | sub all_sources { |
64 | my $self = shift; |
65 | |
66 | my @sources = ($self->read_source, $self->write_source); |
67 | |
68 | return wantarray ? @sources : \@sources; |
69 | } |
70 | |
71 | sub connect_info { |
72 | my( $self, $source_info ) = @_; |
73 | |
74 | my( $info, $global_options, $options, @dsns ); |
75 | |
76 | $info = [ @$source_info ]; |
77 | |
78 | $global_options = ref $info->[-1] eq 'HASH' ? pop( @$info ) : {}; |
79 | if( ref( $options = $info->[0]->[-1] ) eq 'HASH' ) { |
80 | # Local options present in dsn, merge them with global options |
81 | map { $global_options->{$_} = $options->{$_} } keys %$options; |
82 | pop @{$info->[0]}; |
83 | } |
84 | |
85 | # We need to copy-pass $global_options, since connect_info clears it while processing options |
86 | $self->write_source->connect_info( [ @{$info->[0]}, { %$global_options } ] ); |
87 | |
88 | @dsns = map { ($_->[3]->{priority} || 10) => $_ } @{$info}[1..@$info-1]; |
89 | $global_options->{dsns} = \@dsns; |
90 | |
91 | $self->read_source->connect_info( [ 'dbi:Multi:', undef, undef, { %$global_options } ] ); |
92 | } |
93 | |
94 | sub select { |
95 | shift->read_source->select( @_ ); |
96 | } |
97 | sub select_single { |
98 | shift->read_source->select_single( @_ ); |
99 | } |
100 | sub throw_exception { |
101 | shift->read_source->throw_exception( @_ ); |
102 | } |
103 | sub sql_maker { |
104 | shift->read_source->sql_maker( @_ ); |
105 | } |
106 | sub columns_info_for { |
107 | shift->read_source->columns_info_for( @_ ); |
108 | } |
109 | sub sqlt_type { |
110 | shift->read_source->sqlt_type( @_ ); |
111 | } |
112 | sub create_ddl_dir { |
113 | shift->read_source->create_ddl_dir( @_ ); |
114 | } |
115 | sub deployment_statements { |
116 | shift->read_source->deployment_statements( @_ ); |
117 | } |
118 | sub datetime_parser { |
119 | shift->read_source->datetime_parser( @_ ); |
120 | } |
121 | sub datetime_parser_type { |
122 | shift->read_source->datetime_parser_type( @_ ); |
123 | } |
124 | sub build_datetime_parser { |
125 | shift->read_source->build_datetime_parser( @_ ); |
126 | } |
127 | |
128 | sub limit_dialect { |
129 | my $self = shift; |
130 | $self->$_->limit_dialect( @_ ) for( $self->all_sources ); |
131 | } |
132 | sub quote_char { |
133 | my $self = shift; |
134 | $self->$_->quote_char( @_ ) for( $self->all_sources ); |
135 | } |
136 | sub name_sep { |
137 | my $self = shift; |
138 | $self->$_->quote_char( @_ ) for( $self->all_sources ); |
139 | } |
140 | sub disconnect { |
141 | my $self = shift; |
142 | $self->$_->disconnect( @_ ) for( $self->all_sources ); |
143 | } |
144 | sub DESTROY { |
145 | my $self = shift; |
146 | |
147 | undef $self->{write_source}; |
148 | undef $self->{read_sources}; |
149 | } |
150 | |
151 | sub last_insert_id { |
152 | shift->write_source->last_insert_id( @_ ); |
153 | } |
154 | sub insert { |
155 | shift->write_source->insert( @_ ); |
156 | } |
157 | sub update { |
158 | shift->write_source->update( @_ ); |
159 | } |
160 | sub update_all { |
161 | shift->write_source->update_all( @_ ); |
162 | } |
163 | sub delete { |
164 | shift->write_source->delete( @_ ); |
165 | } |
166 | sub delete_all { |
167 | shift->write_source->delete_all( @_ ); |
168 | } |
169 | sub create { |
170 | shift->write_source->create( @_ ); |
171 | } |
172 | sub find_or_create { |
173 | shift->write_source->find_or_create( @_ ); |
174 | } |
175 | sub update_or_create { |
176 | shift->write_source->update_or_create( @_ ); |
177 | } |
178 | sub connected { |
179 | shift->write_source->connected( @_ ); |
180 | } |
181 | sub ensure_connected { |
182 | shift->write_source->ensure_connected( @_ ); |
183 | } |
184 | sub dbh { |
185 | shift->write_source->dbh( @_ ); |
186 | } |
187 | sub txn_begin { |
188 | shift->write_source->txn_begin( @_ ); |
189 | } |
190 | sub txn_commit { |
191 | shift->write_source->txn_commit( @_ ); |
192 | } |
193 | sub txn_rollback { |
194 | shift->write_source->txn_rollback( @_ ); |
195 | } |
196 | sub sth { |
197 | shift->write_source->sth( @_ ); |
198 | } |
199 | sub deploy { |
200 | shift->write_source->deploy( @_ ); |
201 | } |
202 | |
203 | |
204 | sub debugfh { shift->_not_supported( 'debugfh' ) }; |
205 | sub debugcb { shift->_not_supported( 'debugcb' ) }; |
206 | |
207 | sub _not_supported { |
208 | my( $self, $method ) = @_; |
209 | |
210 | die "This Storage does not support $method method."; |
211 | } |
212 | |
213 | =head1 SEE ALSO |
214 | |
215 | L<DBI::Class::Storage::DBI>, L<DBD::Multi>, L<DBI> |
216 | |
217 | =head1 AUTHOR |
218 | |
219 | Norbert Csongrádi <bert@cpan.org> |
220 | |
221 | Peter Siklósi <einon@einon.hu> |
222 | |
223 | =head1 LICENSE |
224 | |
225 | You may distribute this code under the same terms as Perl itself. |
226 | |
227 | =cut |
228 | |
229 | 1; |