use strict;
use warnings;
-use Carp::Clan qw/^DBIx::Class/;
+use Try::Tiny;
+use Scalar::Util qw/weaken blessed refaddr/;
+use DBIx::Class;
+use DBIx::Class::Exception;
+use DBIx::Class::Carp;
+use namespace::clean;
+
+my ($guards_count, $compat_handler, $foreign_handler);
sub new {
my ($class, $storage) = @_;
+ my $guard = {
+ inactivated => 0,
+ storage => $storage,
+ };
+
+ # we are starting with an already set $@ - in order for things to work we need to
+ # be able to recognize it upon destruction - store its weakref
+ # recording it before doing the txn_begin stuff
+ if (defined $@ and $@ ne '') {
+ $guard->{existing_exception_ref} = (ref $@ ne '') ? $@ : \$@;
+ weaken $guard->{existing_exception_ref};
+ }
+
$storage->txn_begin;
- bless [ 0, $storage ], ref $class || $class;
+
+ $guard->{dbh} = $storage->_dbh;
+ weaken $guard->{dbh};
+
+ bless $guard, ref $class || $class;
+
+ # install a callback carefully
+ if (DBIx::Class::_ENV_::INVISIBLE_DOLLAR_AT and !$guards_count) {
+
+ # if the thrown exception is a plain string, wrap it in our
+ # own exception class
+ # this is actually a pretty cool idea, may very well keep it
+ # after perl is fixed
+ $compat_handler ||= bless(
+ sub {
+ $@ = (blessed($_[0]) or ref($_[0]))
+ ? $_[0]
+ : bless ( { msg => $_[0] }, 'DBIx::Class::Exception')
+ ;
+ die;
+ },
+ '__TxnScopeGuard__FIXUP__',
+ );
+
+ if ($foreign_handler = $SIG{__DIE__}) {
+ $SIG{__DIE__} = bless (
+ sub {
+ # we trust the foreign handler to do whatever it wants, all we do is set $@
+ eval { $compat_handler->(@_) };
+ $foreign_handler->(@_);
+ },
+ '__TxnScopeGuard__FIXUP__',
+ );
+ }
+ else {
+ $SIG{__DIE__} = $compat_handler;
+ }
+ }
+
+ $guards_count++;
+
+ $guard;
}
sub commit {
my $self = shift;
- $self->[1]->txn_commit;
- $self->[0] = 1;
+ $self->{storage}->throw_exception("Refusing to execute multiple commits on scope guard $self")
+ if $self->{inactivated};
+
+ $self->{storage}->txn_commit;
+ $self->{inactivated} = 1;
}
sub DESTROY {
- my ($dismiss, $storage) = @{$_[0]};
+ my $self = shift;
+
+ $guards_count--;
+
+ # don't touch unless it's ours, and there are no more of us left
+ if (
+ DBIx::Class::_ENV_::INVISIBLE_DOLLAR_AT
+ and
+ !$guards_count
+ ) {
+
+ if (ref $SIG{__DIE__} eq '__TxnScopeGuard__FIXUP__') {
+ # restore what we saved
+ if ($foreign_handler) {
+ $SIG{__DIE__} = $foreign_handler;
+ }
+ else {
+ delete $SIG{__DIE__};
+ }
+ }
- return if $dismiss;
+ # make sure we do not leak the foreign one in case it exists
+ undef $foreign_handler;
+ }
+
+ return if $self->{inactivated};
- my $exception = $@;
+ # if our dbh is not ours anymore, the $dbh weakref will go undef
+ $self->{storage}->_verify_pid;
+ return unless $self->{dbh};
- carp 'A DBIx::Class::Storage::TxnScopeGuard went out of scope without explicit commit or error. Rolling back.'
- unless $exception;
+ my $exception = $@ if (
+ defined $@
+ and
+ $@ ne ''
+ and
+ (
+ ! defined $self->{existing_exception_ref}
+ or
+ refaddr( ref $@ eq '' ? \$@ : $@ ) != refaddr($self->{existing_exception_ref})
+ )
+ );
- my $rollback_exception;
{
local $@;
- eval { $storage->txn_rollback };
- $rollback_exception = $@;
- }
- if ($rollback_exception && $rollback_exception !~ /DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION/) {
- if ($exception) {
- $@ = "Transaction aborted: ${exception} "
+ carp 'A DBIx::Class::Storage::TxnScopeGuard went out of scope without explicit commit or error. Rolling back.'
+ unless defined $exception;
+
+ my $rollback_exception;
+ # do minimal connectivity check due to weird shit like
+ # https://rt.cpan.org/Public/Bug/Display.html?id=62370
+ try { $self->{storage}->_seems_connected && $self->{storage}->txn_rollback }
+ catch { $rollback_exception = shift };
+
+ if ( $rollback_exception and (
+ ! defined blessed $rollback_exception
+ or
+ ! $rollback_exception->isa('DBIx::Class::Storage::NESTED_ROLLBACK_EXCEPTION')
+ ) ) {
+ # append our text - THIS IS A TEMPORARY FIXUP!
+ # a real stackable exception object is in the works
+ if (ref $exception eq 'DBIx::Class::Exception') {
+ $exception->{msg} = "Transaction aborted: $exception->{msg} "
."Rollback failed: ${rollback_exception}";
- }
- else {
- carp (join ' ',
- "********************* ROLLBACK FAILED!!! ********************",
- "\nA rollback operation failed after the guard went out of scope.",
- 'This is potentially a disastrous situation, check your data for',
- "consistency: $rollback_exception"
- );
+ }
+ elsif ($exception) {
+ $exception = "Transaction aborted: ${exception} "
+ ."Rollback failed: ${rollback_exception}";
+ }
+ else {
+ carp (join ' ',
+ "********************* ROLLBACK FAILED!!! ********************",
+ "\nA rollback operation failed after the guard went out of scope.",
+ 'This is potentially a disastrous situation, check your data for',
+ "consistency: $rollback_exception"
+ );
+ }
}
}
+
+ $@ = $exception unless DBIx::Class::_ENV_::INVISIBLE_DOLLAR_AT;
}
1;
=head1 DESCRIPTION
An object that behaves much like L<Scope::Guard>, but hardcoded to do the
-right thing with transactions in DBIx::Class.
+right thing with transactions in DBIx::Class.
=head1 METHODS
=head2 commit
Commit the transaction, and stop guarding the scope. If this method is not
-called and this object goes out of scope (i.e. an exception is thrown) then
+called and this object goes out of scope (e.g. an exception is thrown) then
the transaction is rolled back, via L<DBIx::Class::Storage/txn_rollback>
=cut
Ash Berlin, 2008.
-Insipred by L<Scope::Guard> by chocolateboy.
+Inspired by L<Scope::Guard> by chocolateboy.
This module is free software. It may be used, redistributed and/or modified
under the same terms as Perl itself.