use strict;
use warnings;
-use UNIVERSAL::require;
+
+use Carp::Clan qw/^DBIx::Class/;
use base qw/DBIx::Class/;
-__PACKAGE__->load_components(qw/Exception/);
__PACKAGE__->mk_classdata('class_mappings' => {});
__PACKAGE__->mk_classdata('source_registrations' => {});
-__PACKAGE__->mk_classdata('storage_type' => 'DBI');
+__PACKAGE__->mk_classdata('storage_type' => '::DBI');
__PACKAGE__->mk_classdata('storage');
=head1 NAME
=head1 SYNOPSIS
-in My/Schema.pm
-
package My::Schema;
-
use base qw/DBIx::Class::Schema/;
-
+
+ # load My::Schema::Foo, My::Schema::Bar, My::Schema::Baz
__PACKAGE__->load_classes(qw/Foo Bar Baz/);
-in My/Schema/Foo.pm
-
package My::Schema::Foo;
-
use base qw/DBIx::Class/;
-
__PACKAGE__->load_components(qw/PK::Auto::Pg Core/); # for example
__PACKAGE__->table('foo');
- ...
-
-in My/DB.pm
-
- use My::Schema;
- My::Schema->compose_connection('My::DB', $dsn, $user, $pass, $attrs);
+ # Elsewhere in your code:
+ my $schema1 = My::Schema->connect(
+ $dsn,
+ $user,
+ $password,
+ $attrs
+ );
-then in app code
+ my $schema2 = My::Schema->connect( ... );
- my @obj = My::DB::Foo->search({}); # My::DB::Foo isa My::Schema::Foo My::DB
+ # fetch objects using My::Schema::Foo
+ my $resultset = $schema1->resultset('Foo')->search( ... );
+ my @objects = $schema2->resultset('Foo')->search( ... );
=head1 DESCRIPTION
-Creates database classes based on a schema. This allows you to have more than
-one concurrent connection using the same database classes, by making
-subclasses under a new namespace for each connection. If you only need one
-class, you should probably use L<DBIx::Class::DB> directly instead.
+Creates database classes based on a schema. This is the recommended way to
+use L<DBIx::Class> and allows you to use more than one concurrent connection
+with your classes.
NB: If you're used to L<Class::DBI> it's worth reading the L</SYNOPSIS>
carefully as DBIx::Class does things a little differently. Note in
=head1 METHODS
-=head2 register_class <moniker> <component_class>
+=head2 register_class
-Registers a class which isa ResultSourceInstance; equivalent to calling
+=head3 Arguments: <moniker> <component_class>
+
+Registers a class which isa ResultSourceProxy; equivalent to calling
$schema->register_source($moniker, $class->result_source_instance);
$self->register_source($moniker => $to_register->result_source_instance);
}
-=head2 register_source <moniker> <result source>
+=head2 register_source
+
+=head3 Arguments: <moniker> <result source>
Registers the result source in the schema with the given moniker
# if we got here, they probably passed a full class name
my $mapped = $self->class_mappings->{$moniker};
- die "Can't find source for ${moniker}"
+ $self->throw_exception("Can't find source for ${moniker}")
unless $mapped && exists $sreg->{$mapped};
return $sreg->{$mapped};
}
return $self->source($moniker)->resultset;
}
-=head2 load_classes [<classes>, (<class>, <class>), {<namespace> => [<classes>]}]
+=head2 load_classes
+
+=head3 Arguments: [<classes>, (<class>, <class>), {<namespace> => [<classes>]}]
Uses L<Module::Find> to find all classes under the database class' namespace,
or uses the classes you select. Then it loads the component (using L<use>),
}
} else {
eval "require Module::Find;";
- $class->throw("No arguments to load_classes and couldn't load".
+ $class->throw_exception("No arguments to load_classes and couldn't load".
" Module::Find ($@)") if $@;
my @comp = map { substr $_, length "${class}::" } Module::Find::findallmod($class);
$comps_for{$class} = \@comp;
die $@ unless $@ =~ /Can't locate/;
}
$class->register_class($comp => $comp_class);
+ # if $class->can('result_source_instance');
}
}
}
-=head2 compose_connection <target> <@db_info>
+=head2 compose_connection
+
+=head3 Arguments: <target> <@db_info>
This is the most important method in this class. it takes a target namespace,
as well as dbh connection info, and creates a L<DBIx::Class::DB> class as
sub compose_connection {
my ($self, $target, @info) = @_;
- my $base = 'DBIx::Class::ResultSetInstance';
- $base->require;
+ my $base = 'DBIx::Class::ResultSetProxy';
+ eval "require ${base};";
+ $self->throw_exception("No arguments to load_classes and couldn't load".
+ " ${base} ($@)") if $@;
+
+ if ($self eq $target) {
+ # Pathological case, largely caused by the docs on early C::M::DBIC::Plain
+ foreach my $moniker ($self->sources) {
+ my $source = $self->source($moniker);
+ my $class = $source->result_class;
+ $self->inject_base($class, $base);
+ $class->mk_classdata(resultset_instance => $source->resultset);
+ $class->mk_classdata(class_resolver => $self);
+ }
+ $self->connection(@info);
+ return $self;
+ }
+
my $schema = $self->compose_namespace($target, $base);
+ {
+ no strict 'refs';
+ *{"${target}::schema"} = sub { $schema };
+ }
+
$schema->connection(@info);
foreach my $moniker ($schema->sources) {
my $source = $schema->source($moniker);
}
{
no strict 'refs';
- *{"${target}::schema"} =
- sub { $schema };
foreach my $meth (qw/class source resultset/) {
*{"${target}::${meth}"} =
sub { shift->schema->$meth(@_) };
return $schema;
}
-=head2 setup_connection_class <$target> <@info>
+=head2 setup_connection_class
+
+=head3 Arguments: <$target> <@info>
Sets up a database connection class to inject between the schema
and the subclasses the schema creates.
$target->connection(@info);
}
-=head2 connection(@args)
+=head2 connection
+
+=head3 Arguments: (@args)
Instantiates a new Storage object of type storage_type and passes the
-arguments to $storage->connection_info. Sets the connection in-place on
+arguments to $storage->connect_info. Sets the connection in-place on
the schema.
=cut
sub connection {
my ($self, @info) = @_;
- my $storage_class = 'DBIx::Class::Storage::'.$self->storage_type;
- $storage_class->require;
+ my $storage_class = $self->storage_type;
+ $storage_class = 'DBIx::Class::Storage'.$storage_class
+ if $storage_class =~ m/^::/;
+ eval "require ${storage_class};";
+ $self->throw_exception("No arguments to load_classes and couldn't load".
+ " ${storage_class} ($@)") if $@;
my $storage = $storage_class->new;
$storage->connect_info(\@info);
$self->storage($storage);
return $self;
}
-=head2 connect(@info)
+=head2 connect
+
+=head3 Arguments: (@info)
Conveneience method, equivalent to $schema->clone->connection(@info)
=cut
-sub connect { shift->clone->connection(@_) };
+sub connect { shift->clone->connection(@_) }
+
+=head2 txn_begin
+
+Begins a transaction (does nothing if AutoCommit is off).
+
+=cut
+
+sub txn_begin { shift->storage->txn_begin }
+
+=head2 txn_commit
+
+Commits the current transaction.
+
+=cut
+
+sub txn_commit { shift->storage->txn_commit }
+
+=head2 txn_rollback
+
+Rolls back the current transaction.
+
+=cut
+
+sub txn_rollback { shift->storage->txn_rollback }
+
+=head2 txn_do
+
+=head3 Arguments: <coderef>, [@coderef_args]
+
+Executes <coderef> with (optional) arguments <@coderef_args> transactionally,
+returning its result (if any). If an exception is caught, a rollback is issued
+and the exception is rethrown. If the rollback fails, (i.e. throws an
+exception) an exception is thrown that includes a "Rollback failed" message.
+
+For example,
+
+ my $foo = $schema->resultset('foo')->find(1);
+
+ my $coderef = sub {
+ my ($foo, @bars) = @_;
+
+ # If any one of these fails, the entire transaction fails
+ $foo->create_related('bars', {
+ col => $_
+ }) foreach (@bars);
+
+ return $foo->bars;
+ };
+
+ my $rs;
+ eval {
+ $rs = $schema->txn_do($coderef, $foo, qw/foo bar baz/);
+ };
+
+ if ($@) {
+ my $error = $@;
+ if ($error =~ /Rollback failed/) {
+ die "something terrible has happened!";
+ } else {
+ deal_with_failed_transaction();
+ die $error;
+ }
+ }
+
+Nested transactions should work as expected (i.e. only the outermost
+transaction will issue a txn_commit on the Schema's storage)
+
+=cut
+
+sub txn_do {
+ my ($self, $coderef, @args) = @_;
+
+ ref $self or $self->throw_exception('Cannot execute txn_do as a '.
+ 'class method');
+
+ my (@return_values, $return_value);
+
+ $self->txn_begin; # If this throws an exception, no rollback is needed
+
+ my $wantarray = wantarray; # Need to save this since it's reset in eval{}
+
+ eval {
+ # Need to differentiate between scalar/list context to allow for returning
+ # a list in scalar context to get the size of the list
+ if ($wantarray) {
+ @return_values = $coderef->(@args);
+ } else {
+ $return_value = $coderef->(@args);
+ }
+ $self->txn_commit;
+ };
+
+ if ($@) {
+ my $error = $@;
+
+ eval {
+ $self->txn_rollback;
+ };
+
+ if ($@) {
+ my $rollback_error = $@;
+ my $exception_class = "DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION";
+ $self->throw_exception($error) # propagate nested rollback
+ if $rollback_error =~ /$exception_class/;
+
+ $self->throw_exception("Transaction aborted: $error. Rollback failed: ".
+ $rollback_error);
+ } else {
+ $self->throw_exception($error); # txn failed but rollback succeeded
+ }
+ }
+
+ return $wantarray ? @return_values : $return_value;
+}
=head2 clone
return $clone;
}
+=head2 populate
+
+=head3 Arguments: ($moniker, \@data);
+
+Populates the source registered with the given moniker with the supplied data.
+@data should be a list of listrefs, the first containing column names, the
+second matching values - i.e.
+
+ $schema->populate('Foo', [
+ [ qw/foo_id foo_string/ ],
+ [ 1, 'One' ],
+ [ 2, 'Two' ],
+ ...
+ ]);
+
+=cut
+
+sub populate {
+ my ($self, $name, $data) = @_;
+ my $rs = $self->resultset($name);
+ my @names = @{shift(@$data)};
+ foreach my $item (@$data) {
+ my %create;
+ @create{@names} = @$item;
+ $rs->create(\%create);
+ }
+}
+
+=head2 throw_exception
+
+Defaults to using Carp::Clan to report errors from user perspective.
+
+=cut
+
+sub throw_exception {
+ my ($self) = shift;
+ croak @_;
+}
+
1;
=head1 AUTHORS