use warnings;
use base qw/DBIx::Class/;
+use mro 'c3';
-use Scalar::Util qw/weaken/;
-use Carp::Clan qw/^DBIx::Class/;
+use DBIx::Class::Exception;
+use Scalar::Util();
+use IO::File;
+use DBIx::Class::Storage::TxnScopeGuard;
+use Try::Tiny;
+use namespace::clean;
-__PACKAGE__->load_components(qw/AccessorGroup/);
__PACKAGE__->mk_group_accessors('simple' => qw/debug debugobj schema/);
+__PACKAGE__->mk_group_accessors('inherited' => 'cursor_class');
+
+__PACKAGE__->cursor_class('DBIx::Class::Cursor');
+
+sub cursor { shift->cursor_class(@_); }
package # Hide from PAUSE
DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION;
$new->set_schema($schema);
$new->debugobj(new DBIx::Class::Storage::Statistics());
- my $fh;
+ #my $fh;
my $debug_env = $ENV{DBIX_CLASS_STORAGE_DBI_DEBUG}
|| $ENV{DBIC_TRACE};
- if (defined($debug_env) && ($debug_env =~ /=(.+)$/)) {
- $fh = IO::File->new($1, 'w')
- or $new->throw_exception("Cannot open trace file $1");
- } else {
- $fh = IO::File->new('>&STDERR');
- }
-
- $new->debugfh($fh);
$new->debug(1) if $debug_env;
$new;
sub set_schema {
my ($self, $schema) = @_;
$self->schema($schema);
- weaken($self->{schema}) if ref $self->{schema};
+ Scalar::Util::weaken($self->{schema}) if ref $self->{schema};
}
=head2 connected
sub throw_exception {
my $self = shift;
- $self->schema->throw_exception(@_) if $self->schema;
- croak @_;
+ if ($self->schema) {
+ $self->schema->throw_exception(@_);
+ }
+ else {
+ DBIx::Class::Exception->throw(@_);
+ }
}
=head2 txn_do
};
my $rs;
- eval {
+ try {
$rs = $schema->txn_do($coderef);
- };
-
- if ($@) { # Transaction failed
+ } catch {
+ my $error = shift;
+ # Transaction failed
die "something terrible has happened!" #
- if ($@ =~ /Rollback failed/); # Rollback failed
+ if ($error =~ /Rollback failed/); # Rollback failed
deal_with_failed_transaction();
- }
+ };
In a nested transaction (calling txn_do() from within a txn_do() coderef) only
the outermost transaction will issue a L</txn_commit>, and txn_do() can be
called in void, scalar and list context and it will behave as expected.
+Please note that all of the code in your coderef, including non-DBIx::Class
+code, is part of a transaction. This transaction may fail out halfway, or
+it may get partially double-executed (in the case that our DB connection
+failed halfway through the transaction, in which case we reconnect and
+restart the txn). Therefore it is best that any side-effects in your coderef
+are idempotent (that is, can be re-executed multiple times and get the
+same result), and that you check up on your side-effects in the case of
+transaction failure.
+
=cut
sub txn_do {
$self->txn_begin; # If this throws an exception, no rollback is needed
my $wantarray = wantarray; # Need to save this since the context
- # inside the eval{} block is independent
+ # inside the try{} block is independent
# of the context that called txn_do()
- eval {
+ try {
# Need to differentiate between scalar/list context to allow for
# returning a list in scalar context to get the size of the list
$coderef->(@args);
}
$self->txn_commit;
- };
-
- if ($@) {
- my $error = $@;
+ }
+ catch {
+ my $error = shift;
- eval {
+ try {
$self->txn_rollback;
- };
-
- if ($@) {
- my $rollback_error = $@;
+ } catch {
my $exception_class = "DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION";
$self->throw_exception($error) # propagate nested rollback
- if $rollback_error =~ /$exception_class/;
+ if $_ =~ /$exception_class/;
$self->throw_exception(
- "Transaction aborted: $error. Rollback failed: ${rollback_error}"
+ "Transaction aborted: $error. Rollback failed: $_"
);
- } else {
- $self->throw_exception($error); # txn failed but rollback succeeded
}
- }
+ $self->throw_exception($error); # txn failed but rollback succeeded
+ };
return $wantarray ? @return_values : $return_value;
}
Issues a commit of the current transaction.
+It does I<not> perform an actual storage commit unless there's a DBIx::Class
+transaction currently in effect (i.e. you called L</txn_begin>).
+
=cut
sub txn_commit { die "Virtual method!" }
sub txn_rollback { die "Virtual method!" }
+=head2 svp_begin
+
+Arguments: $savepoint_name?
+
+Created a new savepoint using the name provided as argument. If no name
+is provided, a random name will be used.
+
+=cut
+
+sub svp_begin { die "Virtual method!" }
+
+=head2 svp_release
+
+Arguments: $savepoint_name?
+
+Release the savepoint provided as argument. If none is provided,
+release the savepoint created most recently. This will implicitly
+release all savepoints created after the one explicitly released as well.
+
+=cut
+
+sub svp_release { die "Virtual method!" }
+
+=head2 svp_rollback
+
+Arguments: $savepoint_name?
+
+Rollback to the savepoint provided as argument. If none is provided,
+rollback to the savepoint created most recently. This will implicitly
+release all savepoints created after the savepoint we rollback to.
+
+=cut
+
+sub svp_rollback { die "Virtual method!" }
+
+=for comment
+
+=head2 txn_scope_guard
+
+An alternative way of transaction handling based on
+L<DBIx::Class::Storage::TxnScopeGuard>:
+
+ my $txn_guard = $storage->txn_scope_guard;
+
+ $row->col1("val1");
+ $row->update;
+
+ $txn_guard->commit;
+
+If an exception occurs, or the guard object otherwise leaves the scope
+before C<< $txn_guard->commit >> is called, the transaction will be rolled
+back by an explicit L</txn_rollback> call. In essence this is akin to
+using a L</txn_begin>/L</txn_commit> pair, without having to worry
+about calling L</txn_rollback> at the right places. Note that since there
+is no defined code closure, there will be no retries and other magic upon
+database disconnection. If you need such functionality see L</txn_do>.
+
+=cut
+
+sub txn_scope_guard {
+ return DBIx::Class::Storage::TxnScopeGuard->new($_[0]);
+}
+
=head2 sql_maker
Returns a C<sql_maker> object - normally an object of class
-C<DBIC::SQL::Abstract>.
+C<DBIx::Class::SQLAHacks>.
=cut
=head2 debugfh
Set or retrieve the filehandle used for trace/debug output. This should be
-an IO::Handle compatible ojbect (only the C<print> method is used. Initially
+an IO::Handle compatible object (only the C<print> method is used. Initially
set to be STDERR - although see information on the
L<DBIC_TRACE> environment variable.
}
}
-=head2 cursor
+=head2 cursor_class
The cursor class for this Storage object.
=cut
-sub cursor { die "Virtual method!" }
-
=head2 deploy
Deploy the tables to storage (CREATE TABLE and friends in a SQL-based
=head2 columns_info_for
-Returns database type info for the given table's columns.
+Returns metadata for the given source's columns. This
+is *deprecated*, and will be removed before 1.0. You should
+be specifying the metadata yourself if you need it.
=cut
written to the file C</path/name>.
This environment variable is checked when the storage object is first
-created (when you call connect on your schema). So, run-time changes
-to this environment variable will not take effect unless you also
+created (when you call connect on your schema). So, run-time changes
+to this environment variable will not take effect unless you also
re-connect on your schema.
=head2 DBIX_CLASS_STORAGE_DBI_DEBUG
Old name for DBIC_TRACE
+=head1 SEE ALSO
+
+L<DBIx::Class::Storage::DBI> - reference storage implementation using
+SQL::Abstract and DBI.
+
=head1 AUTHORS
Matt S. Trout <mst@shadowcatsystems.co.uk>