use base qw/DBIx::Class/;
use mro 'c3';
-use DBIx::Class::Exception;
-use Scalar::Util 'weaken';
+{
+ package # Hide from PAUSE
+ DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION;
+ use base 'DBIx::Class::Exception';
+}
+
+use DBIx::Class::Carp;
+use Scalar::Util qw/blessed weaken/;
use DBIx::Class::Storage::TxnScopeGuard;
use Try::Tiny;
use namespace::clean;
-__PACKAGE__->mk_group_accessors('simple' => qw/debug schema/);
-__PACKAGE__->mk_group_accessors('component_class' => 'cursor_class');
+__PACKAGE__->mk_group_accessors(simple => qw/debug schema transaction_depth auto_savepoint savepoints/);
+__PACKAGE__->mk_group_accessors(component_class => 'cursor_class');
__PACKAGE__->cursor_class('DBIx::Class::Cursor');
sub cursor { shift->cursor_class(@_); }
-package # Hide from PAUSE
- DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION;
-
-use overload '"' => sub {
- 'DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION'
-};
-
-sub new {
- my $class = shift;
- my $self = {};
- return bless $self, $class;
-}
-
-package DBIx::Class::Storage;
-
=head1 NAME
DBIx::Class::Storage - Generic Storage Handler
$self = ref $self if ref $self;
- my $new = {};
- bless $new, $self;
+ my $new = bless( {
+ transaction_depth => 0,
+ savepoints => [],
+ }, $self);
$new->set_schema($schema);
$new->debug(1)
} catch {
my $error = shift;
# Transaction failed
- die "something terrible has happened!" #
+ die "something terrible has happened!"
if ($error =~ /Rollback failed/); # Rollback failed
deal_with_failed_transaction();
ref $coderef eq 'CODE' or $self->throw_exception
('$coderef must be a CODE reference');
- my (@return_values, $return_value);
+ my $abort_txn = sub {
+ my ($self, $exception) = @_;
+
+ my $rollback_exception = try { $self->txn_rollback; undef } catch { shift };
- $self->txn_begin; # If this throws an exception, no rollback is needed
+ if ( $rollback_exception and (
+ ! defined blessed $rollback_exception
+ or
+ ! $rollback_exception->isa('DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION')
+ ) ) {
+ $self->throw_exception(
+ "Transaction aborted: ${exception}. "
+ . "Rollback failed: ${rollback_exception}"
+ );
+ }
+ $self->throw_exception($exception);
+ };
- my $wantarray = wantarray; # Need to save this since the context
- # inside the try{} block is independent
- # of the context that called txn_do()
+ # take a ref instead of a copy, to preserve coderef @_ aliasing semantics
my $args = \@_;
- try {
+ # do not turn on until a succesful txn_begin
+ my $attempt_commit = 0;
- # Need to differentiate between scalar/list context to allow for
- # returning a list in scalar context to get the size of the list
- if ($wantarray) {
- # list context
- @return_values = $coderef->(@$args);
- } elsif (defined $wantarray) {
- # scalar context
- $return_value = $coderef->(@$args);
- } else {
- # void context
- $coderef->(@$args);
- }
- $self->txn_commit;
+ my $txn_init_depth = $self->transaction_depth;
+
+ try {
+ $self->txn_begin;
+ $attempt_commit = 1;
+ $coderef->(@$args)
}
catch {
- my $error = shift;
+ $attempt_commit = 0;
- try {
- $self->txn_rollback;
- } catch {
- my $exception_class = "DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION";
- $self->throw_exception($error) # propagate nested rollback
- if $_ =~ /$exception_class/;
+ # init depth of > 0 implies nesting or non-autocommit (either way no retry)
+ if($txn_init_depth or $self->connected ) {
+ $abort_txn->($self, $_);
+ }
+ else {
+ carp "Retrying txn_do($coderef) after catching disconnected exception: $_"
+ if $ENV{DBIC_STORAGE_RETRY_DEBUG};
- $self->throw_exception(
- "Transaction aborted: $error. Rollback failed: $_"
- );
+ $self->_populate_dbh;
+
+ # if txn_depth is > 1 this means something was done to the
+ # original $dbh, otherwise we would not get past the if() above
+ $self->throw_exception(sprintf
+ 'Unexpected transaction depth of %d on freshly connected handle',
+ $self->transaction_depth,
+ ) if $self->transaction_depth;
+
+ $self->txn_begin;
+ $attempt_commit = 1;
+
+ try {
+ $coderef->(@$args)
+ }
+ catch {
+ $attempt_commit = 0;
+ $abort_txn->($self, $_)
+ };
+ };
+ }
+ finally {
+ if ($attempt_commit) {
+ my $delta_txn = (1 + $txn_init_depth) - $self->transaction_depth;
+
+ if ($delta_txn) {
+ # a rollback in a top-level txn_do is valid-ish (seen in the wild and our own tests)
+ carp "Unexpected reduction of transaction depth by $delta_txn after execution of $coderef, skipping txn_do's commit"
+ unless $delta_txn == 1 and $self->transaction_depth == 0;
+ }
+ else {
+ $self->txn_commit;
+ }
}
- $self->throw_exception($error); # txn failed but rollback succeeded
};
-
- return wantarray ? @return_values : $return_value;
}
=head2 txn_begin
=cut
-sub txn_begin { die "Virtual method!" }
+sub txn_begin {
+ my $self = shift;
+
+ if($self->transaction_depth == 0) {
+ $self->debugobj->txn_begin()
+ if $self->debug;
+ $self->_exec_txn_begin;
+ }
+ elsif ($self->auto_savepoint) {
+ $self->svp_begin;
+ }
+ $self->{transaction_depth}++;
+
+}
=head2 txn_commit
=cut
-sub txn_commit { die "Virtual method!" }
+sub txn_commit {
+ my $self = shift;
+
+ if ($self->transaction_depth == 1) {
+ $self->debugobj->txn_commit() if $self->debug;
+ $self->_exec_txn_commit;
+ $self->{transaction_depth}--;
+ }
+ elsif($self->transaction_depth > 1) {
+ $self->{transaction_depth}--;
+ $self->svp_release if $self->auto_savepoint;
+ }
+ else {
+ $self->throw_exception( 'Refusing to commit without a started transaction' );
+ }
+}
=head2 txn_rollback
=cut
-sub txn_rollback { die "Virtual method!" }
+sub txn_rollback {
+ my $self = shift;
+
+ if ($self->transaction_depth == 1) {
+ $self->debugobj->txn_rollback() if $self->debug;
+ $self->_exec_txn_rollback;
+ $self->{transaction_depth}--;
+ }
+ elsif ($self->transaction_depth > 1) {
+ $self->{transaction_depth}--;
+
+ if ($self->auto_savepoint) {
+ $self->svp_rollback;
+ $self->svp_release;
+ }
+ else {
+ DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION->throw(
+ "A txn_rollback in nested transaction is ineffective! (depth $self->{transaction_depth})"
+ );
+ }
+ }
+ else {
+ $self->throw_exception( 'Refusing to roll back without a started transaction' );
+ }
+}
=head2 svp_begin
=cut
-sub svp_begin { die "Virtual method!" }
+sub svp_begin {
+ my ($self, $name) = @_;
+
+ $self->throw_exception ("You can't use savepoints outside a transaction")
+ unless $self->transaction_depth;
+
+ my $exec = $self->can('_exec_svp_begin')
+ or $self->throw_exception ("Your Storage implementation doesn't support savepoints");
+
+ $name = $self->_svp_generate_name
+ unless defined $name;
+
+ push @{ $self->{savepoints} }, $name;
+
+ $self->debugobj->svp_begin($name) if $self->debug;
+
+ $exec->($self, $name);
+}
+
+sub _svp_generate_name {
+ my ($self) = @_;
+ return 'savepoint_'.scalar(@{ $self->{'savepoints'} });
+}
+
=head2 svp_release
=cut
-sub svp_release { die "Virtual method!" }
+sub svp_release {
+ my ($self, $name) = @_;
+
+ $self->throw_exception ("You can't use savepoints outside a transaction")
+ unless $self->transaction_depth;
+
+ my $exec = $self->can('_exec_svp_release')
+ or $self->throw_exception ("Your Storage implementation doesn't support savepoints");
+
+ if (defined $name) {
+ my @stack = @{ $self->savepoints };
+ my $svp;
+
+ do { $svp = pop @stack } until $svp eq $name;
+
+ $self->throw_exception ("Savepoint '$name' does not exist")
+ unless $svp;
+
+ $self->savepoints(\@stack); # put back what's left
+ }
+ else {
+ $name = pop @{ $self->savepoints }
+ or $self->throw_exception('No savepoints to release');;
+ }
+
+ $self->debugobj->svp_release($name) if $self->debug;
+
+ $exec->($self, $name);
+}
=head2 svp_rollback
=cut
-sub svp_rollback { die "Virtual method!" }
+sub svp_rollback {
+ my ($self, $name) = @_;
+
+ $self->throw_exception ("You can't use savepoints outside a transaction")
+ unless $self->transaction_depth;
+
+ my $exec = $self->can('_exec_svp_rollback')
+ or $self->throw_exception ("Your Storage implementation doesn't support savepoints");
+
+ if (defined $name) {
+ my @stack = @{ $self->savepoints };
+ my $svp;
+
+ # a rollback doesn't remove the named savepoint,
+ # only everything after it
+ while (@stack and $stack[-1] ne $name) {
+ pop @stack
+ };
+
+ $self->throw_exception ("Savepoint '$name' does not exist")
+ unless @stack;
+
+ $self->savepoints(\@stack); # put back what's left
+ }
+ else {
+ $name = $self->savepoints->[-1]
+ or $self->throw_exception('No savepoints to rollback');;
+ }
+
+ $self->debugobj->svp_rollback($name) if $self->debug;
+
+ $exec->($self, $name);
+}
=for comment
projects / dbsrgits/DBIx-Class.git / blobdiff