1 package DBIx::Class::Storage::TxnScopeGuard;
5 use Scalar::Util qw(weaken blessed refaddr);
7 use DBIx::Class::_Util qw(is_exception detected_reinvoked_destructor);
12 my ($class, $storage) = @_;
19 # we are starting with an already set $@ - in order for things to work we need to
20 # be able to recognize it upon destruction - store its weakref
21 # recording it before doing the txn_begin stuff
23 # FIXME FRAGILE - any eval that fails but *does not* rethrow between here
24 # and the unwind will trample over $@ and invalidate the entire mechanism
25 # There got to be a saner way of doing this...
27 # Deliberately *NOT* using is_exception - if someone left a misbehaving
28 # antipattern value in $@, it's not our business to whine about it
29 if( defined $@ and length $@ ) {
31 $guard->{existing_exception_ref} = (length ref $@) ? $@ : \$@
37 weaken( $guard->{dbh} = $storage->_dbh );
39 bless $guard, ref $class || $class;
47 $self->{storage}->throw_exception("Refusing to execute multiple commits on scope guard $self")
48 if $self->{inactivated};
50 # FIXME - this assumption may be premature: a commit may fail and a rollback
51 # *still* be necessary. Currently I am not aware of such scenarious, but I
52 # also know the deferred constraint handling is *severely* undertested.
53 # Making the change of "fire txn and never come back to this" in order to
54 # address RT#107159, but this *MUST* be reevaluated later.
55 $self->{inactivated} = 1;
56 $self->{storage}->txn_commit;
60 return if &detected_reinvoked_destructor;
62 return if $_[0]->{inactivated};
65 # grab it before we've done volatile stuff below
66 my $current_exception = (
70 ! defined $_[0]->{existing_exception_ref}
72 refaddr( (length ref $@) ? $@ : \$@ ) != refaddr($_[0]->{existing_exception_ref})
80 # if our dbh is not ours anymore, the $dbh weakref will go undef
81 $_[0]->{storage}->_verify_pid unless DBIx::Class::_ENV_::BROKEN_FORK;
82 return unless defined $_[0]->{dbh};
85 carp 'A DBIx::Class::Storage::TxnScopeGuard went out of scope without explicit commit or error. Rolling back'
86 unless defined $current_exception;
90 my $rollback_exception = $_[0]->{storage}->__delicate_rollback(
91 defined $current_exception
96 ! defined $current_exception
99 "********************* ROLLBACK FAILED!!! ********************",
100 "\nA rollback operation failed after the guard went out of scope.",
101 'This is potentially a disastrous situation, check your data for',
102 "consistency: $rollback_exception"
106 $@ = $current_exception
107 if DBIx::Class::_ENV_::UNSTABLE_DOLLARAT;
109 # Dummy NEXTSTATE ensuring the all temporaries on the stack are garbage
110 # collected before leaving this scope. Depending on the code above, this
111 # may very well be just a preventive measure guarding future modifications
121 DBIx::Class::Storage::TxnScopeGuard - Scope-based transaction handling
126 my ($self, $schema) = @_;
128 my $guard = $schema->txn_scope_guard;
130 # Multiple database operations here
137 An object that behaves much like L<Scope::Guard>, but hardcoded to do the
138 right thing with transactions in DBIx::Class.
144 Creating an instance of this class will start a new transaction (by
145 implicitly calling L<DBIx::Class::Storage/txn_begin>. Expects a
146 L<DBIx::Class::Storage> object as its only argument.
150 Commit the transaction, and stop guarding the scope. If this method is not
151 called and this object goes out of scope (e.g. an exception is thrown) then
152 the transaction is rolled back, via L<DBIx::Class::Storage/txn_rollback>
158 L<DBIx::Class::Schema/txn_scope_guard>.
160 L<Scope::Guard> by chocolateboy (inspiration for this module)
162 =head1 FURTHER QUESTIONS?
164 Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
166 =head1 COPYRIGHT AND LICENSE
168 This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
169 by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
170 redistribute it and/or modify it under the same terms as the
171 L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.