File Coverage

blib/lib/DBIx/Class/Storage/TxnScopeGuard.pm

Criterion	Covered	Total	%
statement	54	55	98.1
branch	21	24	87.5
condition	9	15	60.0
subroutine	13	13	100.0
pod	2	2	100.0
total	99	109	90.8

package DBIx::Class::Storage::TxnScopeGuard;

use strict;
use warnings;
use Try::Tiny;
use Scalar::Util qw(weaken blessed refaddr);
use DBIx::Class;
use DBIx::Class::_Util qw(is_exception detected_reinvoked_destructor);
use DBIx::Class::Carp;
use namespace::clean;

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
  #
  # FIXME FRAGILE - any eval that fails but *does not* rethrow between here
  # and the unwind will trample over $@ and invalidate the entire mechanism
  # There got to be a saner way of doing this...
  if (is_exception $@) {
    weaken(
      $guard->{existing_exception_ref} = (ref($@) eq '') ? \$@ : $@
    );
  }

  $storage->txn_begin;

  weaken( $guard->{dbh} = $storage->_dbh );

  bless $guard, ref $class || $class;

  $guard;
}

sub commit {
  my $self = shift;

  $self->{storage}->throw_exception("Refusing to execute multiple commits on scope guard $self")
    if $self->{inactivated};

  # FIXME - this assumption may be premature: a commit may fail and a rollback
  # *still* be necessary. Currently I am not aware of such scenarious, but I
  # also know the deferred constraint handling is *severely* undertested.
  # Making the change of "fire txn and never come back to this" in order to
  # address RT#107159, but this *MUST* be reevaluated later.
  $self->{inactivated} = 1;
  $self->{storage}->txn_commit;
}

sub DESTROY {
  return if &detected_reinvoked_destructor;

  my $self = shift;

  return if $self->{inactivated};

  # if our dbh is not ours anymore, the $dbh weakref will go undef
  $self->{storage}->_verify_pid unless DBIx::Class::_ENV_::BROKEN_FORK;
  return unless $self->{dbh};

  my $exception = $@ if (
    is_exception $@
      and
    (
      ! defined $self->{existing_exception_ref}
        or
      refaddr( ref($@) eq '' ? \$@ : $@ ) != refaddr($self->{existing_exception_ref})
    )
  );

  {
    local $@;

    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: ${rollback_exception}";
      }
      elsif ($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;
}

1;

__END__