package DBIx::Class::Storage::DBI::Cursor;
-use base qw/DBIx::Class::Cursor/;
-
use strict;
use warnings;
+use base qw/DBIx::Class::Cursor/;
+
+use Try::Tiny;
+use Scalar::Util qw/refaddr weaken/;
+use namespace::clean;
+
+__PACKAGE__->mk_group_accessors('simple' =>
+ qw/storage args attrs/
+);
+
=head1 NAME
DBIx::Class::Storage::DBI::Cursor - Object representing a query cursor on a
=head1 SYNOPSIS
my $cursor = $schema->resultset('CD')->cursor();
- my $first_cd = $cursor->next;
+
+ # raw values off the database handle in resultset columns/select order
+ my @next_cd_column_values = $cursor->next;
+
+ # list of all raw values as arrayrefs
+ my @all_cds_column_values = $cursor->all;
=head1 DESCRIPTION
=cut
-sub new {
- my ($class, $storage, $args, $attrs) = @_;
- $class = ref $class if ref $class;
+{
+ my %cursor_registry;
- my $new = {
- storage => $storage,
- args => $args,
- pos => 0,
- attrs => $attrs,
- _dbh_gen => $storage->{_dbh_gen},
- };
+ sub new {
+ my ($class, $storage, $args, $attrs) = @_;
- return bless ($new, $class);
-}
+ my $self = bless {
+ storage => $storage,
+ args => $args,
+ attrs => $attrs,
+ }, ref $class || $class;
-=head2 as_query
+ if (DBIx::Class::_ENV_::HAS_ITHREADS) {
-=over 4
-
-=item Arguments: none
-
-=item Return Value: \[ $sql, @bind ]
+ # quick "garbage collection" pass - prevents the registry
+ # from slowly growing with a bunch of undef-valued keys
+ defined $cursor_registry{$_} or delete $cursor_registry{$_}
+ for keys %cursor_registry;
-=back
-
-Returns the SQL statement and bind vars associated with the invocant.
-
-=cut
+ weaken( $cursor_registry{ refaddr($self) } = $self )
+ }
-sub as_query {
- my $self = shift;
+ return $self;
+ }
- my $storage = $self->{storage};
- my $sql_maker = $storage->sql_maker;
- local $sql_maker->{for};
+ sub CLONE {
+ for (keys %cursor_registry) {
+ # once marked we no longer care about them, hence no
+ # need to keep in the registry, left alone renumber the
+ # keys (all addresses are now different)
+ my $self = delete $cursor_registry{$_}
+ or next;
- my @args = $storage->_select_args(@{$self->{args}});
- my ($sql, $bind) = $storage->_prep_for_execute(@args[0 .. 2], [@args[4 .. $#args]]);
- return \[ "($sql)", @{ $bind || [] }];
+ $self->{_intra_thread} = 1;
+ }
+ }
}
=head2 next
=cut
-sub _dbh_next {
- my ($storage, $dbh, $self) = @_;
+sub next {
+ my $self = shift;
+
+ return if $self->{_done};
+
+ my $sth;
- $self->_check_dbh_gen;
- if ($self->{attrs}{rows} && $self->{pos} >= $self->{attrs}{rows}) {
- $self->{sth}->finish if $self->{sth}->{Active};
- delete $self->{sth};
- $self->{done} = 1;
+ if (
+ $self->{attrs}{software_limit}
+ && $self->{attrs}{rows}
+ && ($self->{_pos}||0) >= $self->{attrs}{rows}
+ ) {
+ if ($sth = $self->sth) {
+ # explicit finish will issue warnings, unlike the DESTROY below
+ $sth->finish if $sth->FETCH('Active');
+ }
+ $self->{_done} = 1;
+ return;
}
- return if $self->{done};
- unless ($self->{sth}) {
- $self->{sth} = ($storage->_select(@{$self->{args}}))[1];
- if ($self->{attrs}{software_limit}) {
- if (my $offset = $self->{attrs}{offset}) {
- $self->{sth}->fetch for 1 .. $offset;
- }
+
+ unless ($sth = $self->sth) {
+ (undef, $sth, undef) = $self->storage->_select( @{$self->{args}} );
+
+ $self->{_results} = [ (undef) x $sth->FETCH('NUM_OF_FIELDS') ];
+ $sth->bind_columns( \( @{$self->{_results}} ) );
+
+ if ( $self->{attrs}{software_limit} and $self->{attrs}{offset} ) {
+ $sth->fetch for 1 .. $self->{attrs}{offset};
}
+
+ $self->sth($sth);
}
- my @row = $self->{sth}->fetchrow_array;
- if (@row) {
- $self->{pos}++;
+
+ if ($sth->fetch) {
+ $self->{_pos}++;
+ return @{$self->{_results}};
} else {
- delete $self->{sth};
- $self->{done} = 1;
+ $self->{_done} = 1;
+ return ();
}
- return @row;
}
-sub next {
- my ($self) = @_;
- $self->{storage}->dbh_do($self->can('_dbh_next'), $self);
-}
=head2 all
=cut
-sub _dbh_all {
- my ($storage, $dbh, $self) = @_;
+sub all {
+ my $self = shift;
+
+ # delegate to DBIC::Cursor which will delegate back to next()
+ if ($self->{attrs}{software_limit}
+ && ($self->{attrs}{offset} || $self->{attrs}{rows})) {
+ return $self->next::method(@_);
+ }
+
+ my $sth;
+
+ if ($sth = $self->sth) {
+ # explicit finish will issue warnings, unlike the DESTROY below
+ $sth->finish if ( ! $self->{_done} and $sth->FETCH('Active') );
+ $self->sth(undef);
+ }
+
+ (undef, $sth) = $self->storage->_select( @{$self->{args}} );
- $self->_check_dbh_gen;
- $self->{sth}->finish if $self->{sth}->{Active};
- delete $self->{sth};
- my ($rv, $sth) = $storage->_select(@{$self->{args}});
return @{$sth->fetchall_arrayref};
}
-sub all {
- my ($self) = @_;
- if ($self->{attrs}{software_limit}
- && ($self->{attrs}{offset} || $self->{attrs}{rows})) {
- return $self->SUPER::all;
+sub sth {
+ my $self = shift;
+
+ if (@_) {
+ delete @{$self}{qw/_pos _done _pid _intra_thread/};
+
+ $self->{sth} = $_[0];
+ $self->{_pid} = $$ if ! DBIx::Class::_ENV_::BROKEN_FORK and $_[0];
+ }
+ elsif ($self->{sth} and ! $self->{_done}) {
+
+ my $invalidate_handle_reason;
+
+ if (DBIx::Class::_ENV_::HAS_ITHREADS and $self->{_intra_thread} ) {
+ $invalidate_handle_reason = 'Multi-thread';
+ }
+ elsif (!DBIx::Class::_ENV_::BROKEN_FORK and $self->{_pid} != $$ ) {
+ $invalidate_handle_reason = 'Multi-process';
+ }
+
+ if ($invalidate_handle_reason) {
+ $self->storage->throw_exception("$invalidate_handle_reason access attempted while cursor in progress (position $self->{_pos})")
+ if $self->{_pos};
+
+ # reinvokes the reset logic above
+ $self->sth(undef);
+ }
}
- $self->{storage}->dbh_do($self->can('_dbh_all'), $self);
+
+ return $self->{sth};
}
=head2 reset
=cut
sub reset {
- my ($self) = @_;
-
- # No need to care about failures here
- eval { $self->{sth}->finish if $self->{sth} && $self->{sth}->{Active} };
- $self->_soft_reset;
+ $_[0]->__finish_sth if $_[0]->{sth};
+ $_[0]->sth(undef);
}
-sub _soft_reset {
- my ($self) = @_;
- delete $self->{sth};
- delete $self->{done};
- $self->{pos} = 0;
- return $self;
+sub DESTROY {
+ $_[0]->__finish_sth if $_[0]->{sth};
}
-sub _check_dbh_gen {
- my ($self) = @_;
-
- if($self->{_dbh_gen} != $self->{storage}->{_dbh_gen}) {
- $self->{_dbh_gen} = $self->{storage}->{_dbh_gen};
- $self->_soft_reset;
- }
-}
+sub __finish_sth {
+ # It is (sadly) extremely important to finish() handles we are about
+ # to lose (due to reset() or a DESTROY() ). $rs->reset is the closest
+ # thing the user has to getting to the underlying finish() API and some
+ # DBDs mandate this (e.g. DBD::InterBase will segfault, DBD::Sybase
+ # won't start a transaction sanely, etc)
+ # We also can't use the accessor here, as it will trigger a fork/thread
+ # check, and resetting a cursor in a child is perfectly valid
-sub DESTROY {
- my ($self) = @_;
+ my $self = shift;
- # None of the reasons this would die matter if we're in DESTROY anyways
- local $@;
- eval { $self->{sth}->finish if $self->{sth} && $self->{sth}->{Active} };
+ # No need to care about failures here
+ try { local $SIG{__WARN__} = sub {}; $self->{sth}->finish } if (
+ $self->{sth} and ! try { ! $self->{sth}->FETCH('Active') }
+ );
}
1;