initial monotonic commit

[dbsrgits/DBIx-Class-DeploymentHandler.git] / lib / DBIx / Class / DeploymentHandler / VersionHandler / Monotonic.pm

diff --git a/lib/DBIx/Class/DeploymentHandler/VersionHandler/Monotonic.pm b/lib/DBIx/Class/DeploymentHandler/VersionHandler/Monotonic.pm
new file mode 100644 (file)
index 0000000..6e7c7c1
--- /dev/null
+++ b/lib/DBIx/Class/DeploymentHandler/VersionHandler/Monotonic.pm
@@ -0,0 +1,68 @@
+package DBIx::Class::DeploymentHandler::VersionHandler::Monotonic;
+use Moose;
+use Carp 'croak';
+
+with 'DBIx::Class::DeploymentHandler::HandlesVersioning';
+
+has schema_version => (
+  isa      => 'Int',
+  is       => 'ro',
+  required => 1,
+);
+
+has database_version => (
+  isa      => 'Int',
+  is       => 'ro',
+  required => 1,
+);
+
+has to_version => (
+  isa        => 'Int',
+  is         => 'ro',
+  lazy_build => 1,
+);
+
+sub _build_to_version { $_[0]->schema_version }
+
+has _version => (
+  is         => 'rw',
+  isa        => 'Int',
+  lazy_build => 1,
+);
+
+sub BUILD {
+  croak "you are trying to upgrade and your current version is greater\n".
+        "than the version you are trying to upgrade to.  Either downgrade\n".
+        "or update your schema" if $_[0]->to_version < $_[0]->_version;
+}
+
+sub _inc_version { $_[0]->_version($_[0]->_version + 1 ) }
+sub _dec_version { $_[0]->_version($_[0]->_version - 1 ) }
+
+sub _build__version { $_[0]->database_version }
+
+sub previous_version_set {
+  my $self = shift;
+  return undef
+    if $self->to_version == $self->_version;
+
+  $self->_dec_version;
+  return [$self->_version, $self->_version + 1];
+}
+
+sub next_version_set {
+  my $self = shift;
+  return undef
+    if $self->to_version == $self->_version;
+
+  $self->_inc_version;
+  return [$self->_version - 1, $self->_version];
+}
+
+__PACKAGE__->meta->make_immutable;
+
+1;
+
+__END__
+
+vim: ts=2 sw=2 expandtab