BEGIN {
use Carp::Clan qw/^DBIx::Class/;
-
- ## Modules required for Replication support not required for general DBIC
- ## use, so we explicitly test for these.
-
- my %replication_required = (
- 'Moose' => '0.87',
- 'MooseX::AttributeHelpers' => '0.21',
- 'MooseX::Types' => '0.16',
- 'namespace::clean' => '0.11',
- 'Hash::Merge' => '0.11'
- );
-
- my @didnt_load;
-
- for my $module (keys %replication_required) {
- eval "use $module $replication_required{$module}";
- push @didnt_load, "$module $replication_required{$module}"
- if $@;
- }
-
- croak("@{[ join ', ', @didnt_load ]} are missing and are required for Replication")
- if @didnt_load;
+ use DBIx::Class;
+ croak('The following modules are required for Replication ' . DBIx::Class::Optional::Dependencies->req_missing_for ('replicated') )
+ unless DBIx::Class::Optional::Dependencies->req_ok_for ('replicated');
}
use Moose;
use DBIx::Class::Storage::DBI::Replicated::Types qw/BalancerClassNamePart DBICSchema DBICStorageDBI/;
use MooseX::Types::Moose qw/ClassName HashRef Object/;
use Scalar::Util 'reftype';
-use Carp::Clan qw/^DBIx::Class/;
-use Hash::Merge 'merge';
+use Hash::Merge;
+use List::Util qw/min max/;
use namespace::clean -except => 'meta';
=head1 SYNOPSIS
The Following example shows how to change an existing $schema to a replicated
-storage type, add some replicated (readonly) databases, and perform reporting
+storage type, add some replicated (read-only) databases, and perform reporting
tasks.
You should set the 'storage_type attribute to a replicated type. You should
also define your arguments, such as which balancer you want and any arguments
that the Pool object should get.
+ my $schema = Schema::Class->clone;
$schema->storage_type( ['::DBI::Replicated', {balancer=>'::Random'}] );
+ $schema->connection(...);
Next, you need to add in the Replicants. Basically this is an array of
arrayrefs, where each arrayref is database connect information. Think of these
Warning: This class is marked BETA. This has been running a production
website using MySQL native replication as its backend and we have some decent
test coverage but the code hasn't yet been stressed by a variety of databases.
-Individual DB's may have quirks we are not aware of. Please use this in first
+Individual DBs may have quirks we are not aware of. Please use this in first
development and pass along your experiences/bug fixes.
This class implements replicated data store for DBI. Currently you can define
to all existing storages. This way our storage class is a drop in replacement
for L<DBIx::Class::Storage::DBI>.
-Read traffic is spread across the replicants (slaves) occuring to a user
+Read traffic is spread across the replicants (slaves) occurring to a user
selected algorithm. The default algorithm is random weighted.
=head1 NOTES
-The consistancy betweeen master and replicants is database specific. The Pool
+The consistency between master and replicants is database specific. The Pool
gives you a method to validate its replicants, removing and replacing them
when they fail/pass predefined criteria. Please make careful use of the ways
to force a query to run against Master when needed.
=head1 REQUIREMENTS
-Replicated Storage has additional requirements not currently part of L<DBIx::Class>
-
- Moose => '0.87',
- MooseX::AttributeHelpers => '0.20',
- MooseX::Types => '0.16',
- namespace::clean => '0.11',
- Hash::Merge => '0.11'
-
-You will need to install these modules manually via CPAN or make them part of the
-Makefile for your distribution.
+Replicated Storage has additional requirements not currently part of
+L<DBIx::Class>. See L<DBIx::Class::Optional::Dependencies> for more details.
=head1 ATTRIBUTES
select
select_single
columns_info_for
+ _dbh_columns_info_for
+ _select
/],
);
=head2 write_handler
-Defines an object that implements the write side of L<BIx::Class::Storage::DBI>.
+Defines an object that implements the write side of L<BIx::Class::Storage::DBI>,
+as well as methods that don't write or read that can be called on only one
+storage, methods that return a C<$dbh>, and any methods that don't make sense to
+run on a replicant.
=cut
handles=>[qw/
on_connect_do
on_disconnect_do
+ on_connect_call
+ on_disconnect_call
connect_info
+ _connect_info
throw_exception
sql_maker
sqlt_type
backup
is_datatype_numeric
+ can_insert_returning
_count_select
_subq_count_select
_subq_update_delete
svp_rollback
svp_begin
svp_release
+ relname_to_table_alias
+ _straight_join_to_node
+ _dbh_last_insert_id
+ _fix_bind_params
+ _default_dbi_connect_attributes
+ _dbi_connect_info
+ auto_savepoint
+ _sqlt_version_ok
+ _query_end
+ bind_attribute_by_data_type
+ transaction_depth
+ _dbh
+ _select_args
+ _dbh_execute_array
+ _sql_maker_args
+ _sql_maker
+ _query_start
+ _sqlt_version_error
+ _per_row_update_delete
+ _dbh_begin_work
+ _dbh_execute_inserts_with_no_binds
+ _select_args_to_query
+ _svp_generate_name
+ _multipk_update_delete
+ source_bind_attributes
+ _normalize_connect_info
+ _parse_connect_do
+ _dbh_commit
+ _execute_array
+ _placeholders_supported
+ _verify_pid
+ savepoints
+ _sqlt_minimum_version
+ _sql_maker_opts
+ _conn_pid
+ _typeless_placeholders_supported
+ _conn_tid
+ _dbh_autocommit
+ _native_data_type
+ _get_dbh
+ sql_maker_class
+ _dbh_rollback
+ _adjust_select_args_for_complex_prefetch
+ _resolve_ident_sources
+ _resolve_column_info
+ _prune_unused_joins
+ _strip_cond_qualifiers
+ _parse_order_by
+ _resolve_aliastypes_from_select_args
+ _execute
+ _do_query
+ _dbh_sth
+ _dbh_execute
+ _prefetch_insert_auto_nextvals
/],
);
=head2 around: connect_info
-Preserve master's C<connect_info> options (for merging with replicants.)
-Also set any Replicated related options from connect_info, such as
+Preserves master's C<connect_info> options (for merging with replicants.)
+Also sets any Replicated-related options from connect_info, such as
C<pool_type>, C<pool_args>, C<balancer_type> and C<balancer_args>.
=cut
my $wantarray = wantarray;
+ my $merge = Hash::Merge->new('LEFT_PRECEDENT');
+
my %opts;
for my $arg (@$info) {
next unless (reftype($arg)||'') eq 'HASH';
- %opts = %{ merge($arg, \%opts) };
+ %opts = %{ $merge->merge($arg, \%opts) };
}
delete $opts{dsn};
if $opts{pool_type};
$self->pool_args(
- merge((delete $opts{pool_args} || {}), $self->pool_args)
+ $merge->merge((delete $opts{pool_args} || {}), $self->pool_args)
);
$self->pool($self->_build_pool)
if $opts{balancer_type};
$self->balancer_args(
- merge((delete $opts{balancer_args} || {}), $self->balancer_args)
+ $merge->merge((delete $opts{balancer_args} || {}), $self->balancer_args)
);
$self->balancer($self->_build_balancer)
my $master = $self->master;
$master->_determine_driver;
Moose::Meta::Class->initialize(ref $master);
+
DBIx::Class::Storage::DBI::Replicated::WithDSN->meta->apply($master);
+ # link pool back to master
+ $self->pool->master($master);
+
$wantarray ? @res : $res;
};
=cut
sub BUILDARGS {
- my ($class, $schema, $storage_type_args, @args) = @_;
+ my ($class, $schema, $storage_type_args, @args) = @_;
return {
schema=>$schema,
for my $r (@args) {
$r = [ $r ] unless reftype $r eq 'ARRAY';
- croak "coderef replicant connect_info not supported"
+ $self->throw_exception('coderef replicant connect_info not supported')
if ref $r->[0] && reftype $r->[0] eq 'CODE';
# any connect_info options?
# merge if two hashes
my @hashes = @$r[$i .. $#{$r}];
- croak "invalid connect_info options"
+ $self->throw_exception('invalid connect_info options')
if (grep { reftype($_) eq 'HASH' } @hashes) != @hashes;
- croak "too many hashrefs in connect_info"
+ $self->throw_exception('too many hashrefs in connect_info')
if @hashes > 2;
- my %opts = %{ merge(reverse @hashes) };
+ my $merge = Hash::Merge->new('LEFT_PRECEDENT');
+ my %opts = %{ $merge->merge(reverse @hashes) };
# delete them
splice @$r, $i+1, ($#{$r} - $i), ();
+# make sure master/replicants opts don't clash
+ my %master_opts = %{ $self->_master_connect_info_opts };
+ if (exists $opts{dbh_maker}) {
+ delete @master_opts{qw/dsn user password/};
+ }
+ delete $master_opts{dbh_maker};
+
# merge with master
- %opts = %{ merge(\%opts, $self->_master_connect_info_opts) };
+ %opts = %{ $merge->merge(\%opts, \%master_opts) };
# update
$r->[$i] = \%opts;
=head2 execute_reliably ($coderef, ?@args)
Given a coderef, saves the current state of the L</read_handler>, forces it to
-use reliable storage (ie sets it to the master), executes a coderef and then
+use reliable storage (e.g. sets it to the master), executes a coderef and then
restores the original state.
Example:
=head2 set_balanced_storage
Sets the current $schema to be use the </balancer> for all reads, while all
-writea are sent to the master only
+writes are sent to the master only
=cut
=head2 debugobj
-set a debug object across all storages
+set a debug object
=cut
sub debugobj {
my $self = shift @_;
- if(@_) {
- foreach my $source ($self->all_storages) {
- $source->debugobj(@_);
- }
- }
- return $self->master->debugobj;
+ return $self->master->debugobj(@_);
}
=head2 debugfh
-set a debugfh object across all storages
+set a debugfh object
=cut
sub debugfh {
my $self = shift @_;
- if(@_) {
- foreach my $source ($self->all_storages) {
- $source->debugfh(@_);
- }
- }
- return $self->master->debugfh;
+ return $self->master->debugfh(@_);
}
=head2 debugcb
-set a debug callback across all storages
+set a debug callback
=cut
sub debugcb {
my $self = shift @_;
- if(@_) {
- foreach my $source ($self->all_storages) {
- $source->debugcb(@_);
- }
- }
- return $self->master->debugcb;
+ return $self->master->debugcb(@_);
}
=head2 disconnect
$self->master->cursor_class;
}
+=head2 cursor
+
+set cursor class on all storages, or return master's, alias for L</cursor_class>
+above.
+
+=cut
+
+sub cursor {
+ my ($self, $cursor_class) = @_;
+
+ if ($cursor_class) {
+ $_->cursor($cursor_class) for $self->all_storages;
+ }
+ $self->master->cursor;
+}
+
+=head2 unsafe
+
+sets the L<DBIx::Class::Storage::DBI/unsafe> option on all storages or returns
+master's current setting
+
+=cut
+
+sub unsafe {
+ my $self = shift;
+
+ if (@_) {
+ $_->unsafe(@_) for $self->all_storages;
+ }
+
+ return $self->master->unsafe;
+}
+
+=head2 disable_sth_caching
+
+sets the L<DBIx::Class::Storage::DBI/disable_sth_caching> option on all storages
+or returns master's current setting
+
+=cut
+
+sub disable_sth_caching {
+ my $self = shift;
+
+ if (@_) {
+ $_->disable_sth_caching(@_) for $self->all_storages;
+ }
+
+ return $self->master->disable_sth_caching;
+}
+
+=head2 lag_behind_master
+
+returns the highest Replicant L<DBIx::Class::Storage::DBI/lag_behind_master>
+setting
+
+=cut
+
+sub lag_behind_master {
+ my $self = shift;
+
+ return max map $_->lag_behind_master, $self->replicants;
+}
+
+=head2 is_replicating
+
+returns true if all replicants return true for
+L<DBIx::Class::Storage::DBI/is_replicating>
+
+=cut
+
+sub is_replicating {
+ my $self = shift;
+
+ return (grep $_->is_replicating, $self->replicants) == ($self->replicants);
+}
+
+=head2 connect_call_datetime_setup
+
+calls L<DBIx::Class::Storage::DBI/connect_call_datetime_setup> for all storages
+
+=cut
+
+sub connect_call_datetime_setup {
+ my $self = shift;
+ $_->connect_call_datetime_setup for $self->all_storages;
+}
+
+sub _populate_dbh {
+ my $self = shift;
+ $_->_populate_dbh for $self->all_storages;
+}
+
+sub _connect {
+ my $self = shift;
+ $_->_connect for $self->all_storages;
+}
+
+sub _rebless {
+ my $self = shift;
+ $_->_rebless for $self->all_storages;
+}
+
+sub _determine_driver {
+ my $self = shift;
+ $_->_determine_driver for $self->all_storages;
+}
+
+sub _driver_determined {
+ my $self = shift;
+
+ if (@_) {
+ $_->_driver_determined(@_) for $self->all_storages;
+ }
+
+ return $self->master->_driver_determined;
+}
+
+sub _init {
+ my $self = shift;
+
+ $_->_init for $self->all_storages;
+}
+
+sub _run_connection_actions {
+ my $self = shift;
+
+ $_->_run_connection_actions for $self->all_storages;
+}
+
+sub _do_connection_actions {
+ my $self = shift;
+
+ if (@_) {
+ $_->_do_connection_actions(@_) for $self->all_storages;
+ }
+}
+
+sub connect_call_do_sql {
+ my $self = shift;
+ $_->connect_call_do_sql(@_) for $self->all_storages;
+}
+
+sub disconnect_call_do_sql {
+ my $self = shift;
+ $_->disconnect_call_do_sql(@_) for $self->all_storages;
+}
+
+sub _seems_connected {
+ my $self = shift;
+
+ return min map $_->_seems_connected, $self->all_storages;
+}
+
+sub _ping {
+ my $self = shift;
+
+ return min map $_->_ping, $self->all_storages;
+}
+
=head1 GOTCHAS
Due to the fact that replicants can lag behind a master, you must take care to