package DBIx::Class::Storage::DBI::Replicated;
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 => '0.54',
- MooseX::AttributeHelpers => '0.12',
- Moose::Util::TypeConstraints => '0.54',
- Class::MOP => '0.63',
- );
-
- 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;
+ die('The following modules are required for Replication ' . DBIx::Class::Optional::Dependencies->req_missing_for ('replicated') . "\n" )
+ unless DBIx::Class::Optional::Dependencies->req_ok_for ('replicated');
}
+use Moose;
use DBIx::Class::Storage::DBI;
use DBIx::Class::Storage::DBI::Replicated::Pool;
use DBIx::Class::Storage::DBI::Replicated::Balancer;
+use DBIx::Class::Storage::DBI::Replicated::Types qw/BalancerClassNamePart DBICSchema DBICStorageDBI/;
+use MooseX::Types::Moose qw/ClassName HashRef Object/;
+use Scalar::Util 'reftype';
+use Hash::Merge;
+use List::Util qw/min max reduce/;
+use Try::Tiny;
+use namespace::clean;
+
+use namespace::clean -except => 'meta';
=head1 NAME
=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.
- ## Change storage_type in your schema class
+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'}] );
-
- ## Add some slaves. Basically this is an array of arrayrefs, where each
- ## arrayref is database connect information
-
+ $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
+arguments as what you'd pass to the 'normal' $schema->connect method.
+
$schema->storage->connect_replicants(
[$dsn1, $user, $pass, \%opts],
[$dsn2, $user, $pass, \%opts],
[$dsn3, $user, $pass, \%opts],
);
-
- ## Now, just use the $schema as normal
+
+Now, just use the $schema as you normally would. Automatically all reads will
+be delegated to the replicants, while writes to the master.
+
$schema->resultset('Source')->search({name=>'etc'});
-
- ## You can force a given query to use a particular storage using the search
- ### attribute 'force_pool'. For example:
-
- my $RS = $schema->resultset('Source')->search(undef, {force_pool=>'master'});
-
- ## Now $RS will force everything (both reads and writes) to use whatever was
- ## setup as the master storage. 'master' is hardcoded to always point to the
- ## Master, but you can also use any Replicant name. Please see:
- ## L<DBIx::Class::Storage::Replicated::Pool> and the replicants attribute for
- ## More. Also see transactions and L</execute_reliably> for alternative ways
- ## to force read traffic to the master.
-
+
+You can force a given query to use a particular storage using the search
+attribute 'force_pool'. For example:
+
+ my $rs = $schema->resultset('Source')->search(undef, {force_pool=>'master'});
+
+Now $rs will force everything (both reads and writes) to use whatever was setup
+as the master storage. 'master' is hardcoded to always point to the Master,
+but you can also use any Replicant name. Please see:
+L<DBIx::Class::Storage::DBI::Replicated::Pool> and the replicants attribute for more.
+
+Also see transactions and L</execute_reliably> for alternative ways to
+force read traffic to the master. In general, you should wrap your statements
+in a transaction when you are reading and writing to the same tables at the
+same time, since your replicants will often lag a bit behind the master.
+
+If you have a multi-statement read only transaction you can force it to select
+a random server in the pool by:
+
+ my $rs = $schema->resultset('Source')->search( undef,
+ { force_pool => $db->storage->read_handler->next_storage }
+ );
+
=head1 DESCRIPTION
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
-gives you a method to validate it's replicants, removing and replacing them
+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 => 1.54
- MooseX::AttributeHelpers => 0.12
- Moose::Util::TypeConstraints => 0.54
- Class::MOP => 0.63
-
-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
has 'schema' => (
is=>'rw',
- isa=>'DBIx::Class::Schema',
+ isa=>DBICSchema,
weak_ref=>1,
required=>1,
);
=head2 pool_type
-Contains the classname which will instantiate the L</pool> object. Defaults
+Contains the classname which will instantiate the L</pool> object. Defaults
to: L<DBIx::Class::Storage::DBI::Replicated::Pool>.
=cut
has 'pool_type' => (
- is=>'ro',
- isa=>'ClassName',
- required=>1,
+ is=>'rw',
+ isa=>ClassName,
default=>'DBIx::Class::Storage::DBI::Replicated::Pool',
handles=>{
'create_pool' => 'new',
=head2 pool_args
Contains a hashref of initialized information to pass to the Balancer object.
-See L<DBIx::Class::Storage::Replicated::Pool> for available arguments.
+See L<DBIx::Class::Storage::DBI::Replicated::Pool> for available arguments.
=cut
has 'pool_args' => (
- is=>'ro',
- isa=>'HashRef',
+ is=>'rw',
+ isa=>HashRef,
lazy=>1,
- required=>1,
default=>sub { {} },
);
=cut
-subtype 'DBIx::Class::Storage::DBI::Replicated::BalancerClassNamePart',
- as 'ClassName';
-
-coerce 'DBIx::Class::Storage::DBI::Replicated::BalancerClassNamePart',
- from 'Str',
- via {
- my $type = $_;
- if($type=~m/^::/) {
- $type = 'DBIx::Class::Storage::DBI::Replicated::Balancer'.$type;
- }
- Class::MOP::load_class($type);
- $type;
- };
-
has 'balancer_type' => (
- is=>'ro',
- isa=>'DBIx::Class::Storage::DBI::Replicated::BalancerClassNamePart',
+ is=>'rw',
+ isa=>BalancerClassNamePart,
coerce=>1,
required=>1,
default=> 'DBIx::Class::Storage::DBI::Replicated::Balancer::First',
=head2 balancer_args
Contains a hashref of initialized information to pass to the Balancer object.
-See L<DBIx::Class::Storage::Replicated::Balancer> for available arguments.
+See L<DBIx::Class::Storage::DBI::Replicated::Balancer> for available arguments.
=cut
has 'balancer_args' => (
- is=>'ro',
- isa=>'HashRef',
+ is=>'rw',
+ isa=>HashRef,
lazy=>1,
required=>1,
default=>sub { {} },
=head2 pool
-Is a <DBIx::Class::Storage::DBI::Replicated::Pool> or derived class. This is a
+Is a L<DBIx::Class::Storage::DBI::Replicated::Pool> or derived class. This is a
container class for one or more replicated databases.
=cut
isa=>'DBIx::Class::Storage::DBI::Replicated::Pool',
lazy_build=>1,
handles=>[qw/
- connect_replicants
+ connect_replicants
replicants
has_replicants
/],
=head2 balancer
-Is a <DBIx::Class::Storage::DBI::Replicated::Balancer> or derived class. This
-is a class that takes a pool (<DBIx::Class::Storage::DBI::Replicated::Pool>)
+Is a L<DBIx::Class::Storage::DBI::Replicated::Balancer> or derived class. This
+is a class that takes a pool (L<DBIx::Class::Storage::DBI::Replicated::Pool>)
=cut
has 'balancer' => (
- is=>'ro',
+ is=>'rw',
isa=>'DBIx::Class::Storage::DBI::Replicated::Balancer',
lazy_build=>1,
handles=>[qw/auto_validate_every/],
has 'master' => (
is=> 'ro',
- isa=>'DBIx::Class::Storage::DBI',
+ isa=>DBICStorageDBI,
lazy_build=>1,
);
=head1 ATTRIBUTES IMPLEMENTING THE DBIx::Storage::DBI INTERFACE
-The following methods are delegated all the methods required for the
+The following methods are delegated all the methods required for the
L<DBIx::Class::Storage::DBI> interface.
-=head2 read_handler
-
-Defines an object that implements the read side of L<BIx::Class::Storage::DBI>.
-
=cut
-has 'read_handler' => (
- is=>'rw',
- isa=>'Object',
- lazy_build=>1,
- handles=>[qw/
- select
- select_single
- columns_info_for
- /],
-);
-
-=head2 write_handler
-
-Defines an object that implements the write side of L<BIx::Class::Storage::DBI>.
-
-=cut
-
-has 'write_handler' => (
- is=>'ro',
- isa=>'Object',
- lazy_build=>1,
- lazy_build=>1,
- handles=>[qw/
+my $method_dispatch = {
+ writer => [qw/
on_connect_do
- on_disconnect_do
+ on_disconnect_do
+ on_connect_call
+ on_disconnect_call
connect_info
+ _connect_info
throw_exception
sql_maker
sqlt_type
create_ddl_dir
deployment_statements
datetime_parser
- datetime_parser_type
+ datetime_parser_type
+ build_datetime_parser
last_insert_id
insert
insert_bulk
txn_commit
txn_rollback
txn_scope_guard
- sth
+ _exec_txn_rollback
+ _exec_txn_begin
+ _exec_txn_commit
deploy
-
- reload_row
+ with_deferred_fk_checks
+ dbh_do
_prep_for_execute
- configure_sqlt
-
+ is_datatype_numeric
+ _count_select
+ svp_rollback
+ svp_begin
+ svp_release
+ relname_to_table_alias
+ _dbh_last_insert_id
+ _default_dbi_connect_attributes
+ _dbi_connect_info
+ _dbic_connect_attributes
+ auto_savepoint
+ _query_start
+ _query_end
+ _format_for_trace
+ _dbi_attrs_for_bind
+ bind_attribute_by_data_type
+ transaction_depth
+ _dbh
+ _select_args
+ _dbh_execute_for_fetch
+ _sql_maker
+ _dbh_execute_inserts_with_no_binds
+ _select_args_to_query
+ _gen_sql_bind
+ _svp_generate_name
+ _normalize_connect_info
+ _parse_connect_do
+ savepoints
+ _sql_maker_opts
+ _conn_pid
+ _dbh_autocommit
+ _native_data_type
+ _get_dbh
+ sql_maker_class
+ _execute
+ _do_query
+ _sth
+ _dbh_sth
+ _dbh_execute
+ /, Class::MOP::Class->initialize('DBIx::Class::Storage::DBIHacks')->get_method_list ],
+ reader => [qw/
+ select
+ select_single
+ columns_info_for
+ _dbh_columns_info_for
+ _select
/],
+ unimplemented => [qw/
+ _arm_global_destructor
+ _verify_pid
+
+ source_bind_attributes
+
+ get_use_dbms_capability
+ set_use_dbms_capability
+ get_dbms_capability
+ set_dbms_capability
+ _dbh_details
+ _dbh_get_info
+
+ sql_limit_dialect
+ sql_quote_char
+ sql_name_sep
+
+ _prefetch_autovalues
+
+ _resolve_bindattrs
+
+ _max_column_bytesize
+ _is_lob_type
+ _is_binary_lob_type
+ _is_text_lob_type
+
+ sth
+ /,(
+ # the capability framework
+ # not sure if CMOP->initialize does evil things to DBIC::S::DBI, fix if a problem
+ grep
+ { $_ =~ /^ _ (?: use | supports | determine_supports ) _ /x }
+ ( Class::MOP::Class->initialize('DBIx::Class::Storage::DBI')->get_all_method_names )
+ )],
+};
+
+if (DBIx::Class::_ENV_::DBICTEST) {
+
+ my $seen;
+ for my $type (keys %$method_dispatch) {
+ for (@{$method_dispatch->{$type}}) {
+ push @{$seen->{$_}}, $type;
+ }
+ }
+
+ if (my @dupes = grep { @{$seen->{$_}} > 1 } keys %$seen) {
+ die(join "\n", '',
+ 'The following methods show up multiple times in ::Storage::DBI::Replicated handlers:',
+ (map { "$_: " . (join ', ', @{$seen->{$_}}) } sort @dupes),
+ '',
+ );
+ }
+
+ if (my @cant = grep { ! DBIx::Class::Storage::DBI->can($_) } keys %$seen) {
+ die(join "\n", '',
+ '::Storage::DBI::Replicated specifies handling of the following *NON EXISTING* ::Storage::DBI methods:',
+ @cant,
+ '',
+ );
+ }
+}
+
+for my $method (@{$method_dispatch->{unimplemented}}) {
+ __PACKAGE__->meta->add_method($method, sub {
+ my $self = shift;
+ $self->throw_exception("$method must not be called on ".(blessed $self).' objects');
+ });
+}
+
+=head2 read_handler
+
+Defines an object that implements the read side of L<BIx::Class::Storage::DBI>.
+
+=cut
+
+has 'read_handler' => (
+ is=>'rw',
+ isa=>Object,
+ lazy_build=>1,
+ handles=>$method_dispatch->{reader},
);
+=head2 write_handler
+
+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<$dbh>, and any methods that don't make sense to
+run on a replicant.
+
+=cut
+
+has 'write_handler' => (
+ is=>'ro',
+ isa=>Object,
+ lazy_build=>1,
+ handles=>$method_dispatch->{writer},
+);
+
+
+
+has _master_connect_info_opts =>
+ (is => 'rw', isa => HashRef, default => sub { {} });
+
+=head2 around: connect_info
+
+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
+
+around connect_info => sub {
+ my ($next, $self, $info, @extra) = @_;
+
+ my $merge = Hash::Merge->new('LEFT_PRECEDENT');
+
+ my %opts;
+ for my $arg (@$info) {
+ next unless (reftype($arg)||'') eq 'HASH';
+ %opts = %{ $merge->merge($arg, \%opts) };
+ }
+ delete $opts{dsn};
+
+ if (@opts{qw/pool_type pool_args/}) {
+ $self->pool_type(delete $opts{pool_type})
+ if $opts{pool_type};
+
+ $self->pool_args(
+ $merge->merge((delete $opts{pool_args} || {}), $self->pool_args)
+ );
+
+ ## Since we possibly changed the pool_args, we need to clear the current
+ ## pool object so that next time it is used it will be rebuilt.
+ $self->clear_pool;
+ }
+
+ if (@opts{qw/balancer_type balancer_args/}) {
+ $self->balancer_type(delete $opts{balancer_type})
+ if $opts{balancer_type};
+
+ $self->balancer_args(
+ $merge->merge((delete $opts{balancer_args} || {}), $self->balancer_args)
+ );
+
+ $self->balancer($self->_build_balancer)
+ if $self->balancer;
+ }
+
+ $self->_master_connect_info_opts(\%opts);
+
+ my @res;
+ if (wantarray) {
+ @res = $self->$next($info, @extra);
+ } else {
+ $res[0] = $self->$next($info, @extra);
+ }
+
+ # Make sure master is blessed into the correct class and apply role to it.
+ 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 : $res[0];
+};
+
=head1 METHODS
This class defines the following methods.
=head2 BUILDARGS
-L<DBIx::Class::Schema> when instantiating it's storage passed itself as the
+L<DBIx::Class::Schema> when instantiating its storage passed itself as the
first argument. So we need to massage the arguments a bit so that all the
bits get put into the correct places.
=cut
sub BUILDARGS {
- my ($class, $schema, $storage_type_args, @args) = @_;
-
+ my ($class, $schema, $storage_type_args, @args) = @_;
+
return {
- schema=>$schema,
- %$storage_type_args,
- @args
+ schema=>$schema,
+ %$storage_type_args,
+ @args
}
}
sub _build_master {
my $self = shift @_;
- DBIx::Class::Storage::DBI->new($self->schema);
+ my $master = DBIx::Class::Storage::DBI->new($self->schema);
+ $master
}
=head2 _build_pool
sub _build_balancer {
my $self = shift @_;
$self->create_balancer(
- pool=>$self->pool,
+ pool=>$self->pool,
master=>$self->master,
%{$self->balancer_args},
);
=head2 around: connect_replicants
All calls to connect_replicants needs to have an existing $schema tacked onto
-top of the args, since L<DBIx::Storage::DBI> needs it.
+top of the args, since L<DBIx::Storage::DBI> needs it, and any C<connect_info>
+options merged with the master, with replicant opts having higher priority.
=cut
-around 'connect_replicants' => sub {
- my ($method, $self, @args) = @_;
- $self->$method($self->schema, @args);
+around connect_replicants => sub {
+ my ($next, $self, @args) = @_;
+
+ for my $r (@args) {
+ $r = [ $r ] unless reftype $r eq 'ARRAY';
+
+ $self->throw_exception('coderef replicant connect_info not supported')
+ if ref $r->[0] && reftype $r->[0] eq 'CODE';
+
+# any connect_info options?
+ my $i = 0;
+ $i++ while $i < @$r && (reftype($r->[$i])||'') ne 'HASH';
+
+# make one if none
+ $r->[$i] = {} unless $r->[$i];
+
+# merge if two hashes
+ my @hashes = @$r[$i .. $#{$r}];
+
+ $self->throw_exception('invalid connect_info options')
+ if (grep { reftype($_) eq 'HASH' } @hashes) != @hashes;
+
+ $self->throw_exception('too many hashrefs in connect_info')
+ if @hashes > 2;
+
+ 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->merge(\%opts, \%master_opts) };
+
+# update
+ $r->[$i] = \%opts;
+ }
+
+ $self->$next($self->schema, @args);
};
=head2 all_storages
my $self = shift @_;
return grep {defined $_ && blessed $_} (
$self->master,
- $self->replicants,
+ values %{ $self->replicants },
);
}
=head2 execute_reliably ($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:
my $reliably = sub {
my $name = shift @_;
$schema->resultset('User')->create({name=>$name});
- my $user_rs = $schema->resultset('User')->find({name=>$name});
+ my $user_rs = $schema->resultset('User')->find({name=>$name});
return $user_rs;
};
sub execute_reliably {
my ($self, $coderef, @args) = @_;
-
+
unless( ref $coderef eq 'CODE') {
$self->throw_exception('Second argument must be a coderef');
}
-
+
##Get copy of master storage
my $master = $self->master;
-
+
##Get whatever the current read hander is
my $current = $self->read_handler;
-
+
##Set the read handler to master
$self->read_handler($master);
-
+
## do whatever the caller needs
my @result;
my $want_array = wantarray;
-
- eval {
+
+ try {
if($want_array) {
@result = $coderef->(@args);
} elsif(defined $want_array) {
($result[0]) = ($coderef->(@args));
} else {
$coderef->(@args);
- }
+ }
+ } catch {
+ $self->throw_exception("coderef returned an error: $_");
+ } finally {
+ ##Reset to the original state
+ $self->read_handler($current);
};
-
- ##Reset to the original state
- $self->read_handler($current);
-
- ##Exception testing has to come last, otherwise you might leave the
- ##read_handler set to master.
-
- if($@) {
- $self->throw_exception("coderef returned an error: $@");
- } else {
- return $want_array ? @result : $result[0];
- }
+
+ return wantarray ? @result : $result[0];
}
=head2 set_reliable_storage
Sets the current $schema to be 'reliable', that is all queries, both read and
write are sent to the master
-
+
=cut
sub set_reliable_storage {
my $self = shift @_;
my $schema = $self->schema;
my $write_handler = $self->schema->storage->write_handler;
-
+
$schema->storage->read_handler($write_handler);
}
=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
sub set_balanced_storage {
my $self = shift @_;
my $schema = $self->schema;
- my $write_handler = $self->schema->storage->balancer;
-
- $schema->storage->read_handler($write_handler);
-}
-
-=head2 around: txn_do ($coderef)
+ my $balanced_handler = $self->schema->storage->balancer;
-Overload to the txn_do method, which is delegated to whatever the
-L<write_handler> is set to. We overload this in order to wrap in inside a
-L</execute_reliably> method.
-
-=cut
-
-around 'txn_do' => sub {
- my($txn_do, $self, $coderef, @args) = @_;
- $self->execute_reliably(sub {$self->$txn_do($coderef, @args)});
-};
+ $schema->storage->read_handler($balanced_handler);
+}
=head2 connected
foreach my $source ($self->all_storages) {
$source->limit_dialect(@_);
}
- return $self->master->quote_char;
+ return $self->master->limit_dialect;
}
=head2 quote_char
if(@_) {
foreach my $source ($self->all_storages) {
$source->debug(@_);
- }
+ }
}
return $self->master->debug;
}
=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 $self->master->debugcb(@_);
}
=head2 disconnect
}
}
+=head2 cursor_class
+
+set cursor class on all storages, or return master's
+
+=cut
+
+sub cursor_class {
+ my ($self, $cursor_class) = @_;
+
+ if ($cursor_class) {
+ $_->cursor_class($cursor_class) for $self->all_storages;
+ }
+ $self->master->cursor_class;
+}
+
+=head2 cursor
+
+set cursor class on all storages, or return master's, alias for L</cursor_class>
+above.
+
+=cut
+
+sub cursor {
+ my ($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;
+}
+
+# not using the normalized_version, because we want to preserve
+# version numbers much longer than the conventional xxx.yyyzzz
+my $numify_ver = sub {
+ my $ver = shift;
+ my @numparts = split /\D+/, $ver;
+ my $format = '%d.' . (join '', ('%06d') x (@numparts - 1));
+
+ return sprintf $format, @numparts;
+};
+sub _server_info {
+ my $self = shift;
+
+ if (not $self->_dbh_details->{info}) {
+ $self->_dbh_details->{info} = (
+ reduce { $a->[0] < $b->[0] ? $a : $b }
+ map [ $numify_ver->($_->{dbms_version}), $_ ],
+ map $_->_server_info, $self->all_storages
+ )->[1];
+ }
+
+ return $self->next::method;
+}
+
+sub _get_server_version {
+ my $self = shift;
+
+ return $self->_server_info->{dbms_version};
+}
+
=head1 GOTCHAS
Due to the fact that replicants can lag behind a master, you must take care to
my $new_schema = $schema->clone;
$new_schema->set_reliable_storage;
-
+
## $new_schema will use only the Master storage for all reads/writes while
## the $schema object will use replicated storage.