Refactor/improve support of DBD::Sybase compiled against FreeTDS (mainly MSSQL)

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / Storage / DBI / Sybase / FreeTDS.pm

diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/FreeTDS.pm b/lib/DBIx/Class/Storage/DBI/Sybase/FreeTDS.pm
new file mode 100644 (file)
index 0000000..feb50fe
--- /dev/null
+++ b/lib/DBIx/Class/Storage/DBI/Sybase/FreeTDS.pm
@@ -0,0 +1,116 @@
+package DBIx::Class::Storage::DBI::Sybase::FreeTDS;
+
+use strict;
+use warnings;
+use base qw/DBIx::Class::Storage::DBI::Sybase/;
+use mro 'c3';
+use Try::Tiny;
+use namespace::clean;
+
+=head1 NAME
+
+DBIx::Class::Storage::DBI::Sybase - Base class for drivers using L<DBD::Sybase>
+over FreeTDS.
+
+=head1 DESCRIPTION
+
+This is the base class for Storages designed to work with L<DBD::Sybase> over
+FreeTDS.
+
+It is a subclass of L<DBIx::Class::Storage::DBI::Sybase>.
+
+=head1 METHODS
+
+=cut
+
+# The subclass storage driver defines _set_autocommit_stmt
+# for MsSQL it is SET IMPLICIT_TRANSACTIONS ON/OFF
+# for proper Sybase it's SET CHAINED ON/OFF
+sub _set_autocommit {
+  my $self = shift;
+
+  if ($self->_dbh_autocommit) {
+    $self->_dbh->do($self->_set_autocommit_stmt(1));
+  } else {
+    $self->_dbh->do($self->_set_autocommit_stmt(0));
+  }
+}
+
+# Handle AutoCommit and SET TEXTSIZE because LongReadLen doesn't work.
+#
+sub _run_connection_actions {
+  my $self = shift;
+
+  # based on LongReadLen in connect_info
+  $self->set_textsize;
+
+  $self->_set_autocommit;
+
+  $self->next::method(@_);
+}
+
+=head2 set_textsize
+
+When using DBD::Sybase with FreeTDS, C<< $dbh->{LongReadLen} >> is not available,
+use this function instead. It does:
+
+  $dbh->do("SET TEXTSIZE $bytes");
+
+Takes the number of bytes, or uses the C<LongReadLen> value from your
+L<connect_info|DBIx::Class::Storage::DBI/connect_info> if omitted, lastly falls
+back to the C<32768> which is the L<DBD::Sybase> default.
+
+=cut
+
+sub set_textsize {
+  my $self = shift;
+  my $text_size =
+    shift
+      ||
+    try { $self->_dbic_cinnect_attributes->{LongReadLen} }
+      ||
+    32768; # the DBD::Sybase default
+
+  $self->_dbh->do("SET TEXTSIZE $text_size");
+}
+
+sub _dbh_begin_work {
+  my $self = shift;
+
+  if ($self->{_in_dbh_do}) {
+    $self->_dbh->do('BEGIN TRAN');
+  }
+  else {
+    $self->dbh_do(sub { $_[1]->do('BEGIN TRAN') });
+  }
+}
+
+sub _dbh_commit {
+  my $self = shift;
+
+  my $dbh = $self->_dbh
+    or $self->throw_exception('cannot COMMIT on a disconnected handle');
+
+  $dbh->do('COMMIT');
+}
+
+sub _dbh_rollback {
+  my $self = shift;
+
+  my $dbh  = $self->_dbh
+    or $self->throw_exception('cannot ROLLBACK on a disconnected handle');
+
+  $dbh->do('ROLLBACK');
+}
+
+1;
+
+=head1 AUTHORS
+
+See L<DBIx::Class/CONTRIBUTORS>.
+
+=head1 LICENSE
+
+You may distribute this code under the same terms as Perl itself.
+
+=cut