Bivio::Cache
# Copyright (c) 2010 bivio Software, Inc. All Rights Reserved.
# $Id$
package Bivio::Cache;
use strict;
use Bivio::Base 'Collection.Attributes';
use Storable ();
use IO::File ();
use Fcntl ();
my($_F) = b_use('IO.File');
my($_FP) = b_use('Type.FilePath');
my($_D) = b_use('Bivio.Die');
my($_BF);
my($_REALM_ID) = b_use('Auth.Realm')->get_general->get_default_id;
my($_SU);
sub init {
b_use('IO.ClassLoader')->map_require_all('Cache');
return;
}
sub handle_commit {
my($proto, $req) = @_;
unlink(_file($proto, $req));
shift->handle_rollback(@_);
return;
}
sub handle_rollback {
my($proto, $req) = @_;
$req->delete(_file($proto, $req));
return;
}
sub internal_compute_no_cache {
return undef;
}
sub internal_realm_id {
return $_REALM_ID;
}
sub internal_retrieve {
my($proto, $req, @extra) = @_;
my($fp) = _file($proto, $req);
return $req->has_keys($fp) ? $req->get($fp)
: _read_and_thaw($fp, $req) || _try_compute($proto, $fp, $req, \@extra);
}
sub _compute {
my($proto, $fp, $req, $extra) = @_;
$_F->mkdir_parent_only($fp, 0750);
my($res) = $proto->internal_compute($req, @$extra);
my($tmp) = "$fp.tmp";
$_F->write($tmp, Storable::nfreeze($res));
$_F->rename($tmp, $fp);
$req->put($fp => $res);
return $res;
}
sub _file {
my($proto, $req) = @_;
return ($_BF ||= b_use('Biz.File'))->absolute_path(
$_FP->join(
'Cache',
$proto->simple_package_name,
$proto->internal_realm_id($req),
),
);
}
sub _read_and_thaw {
my($fp, $req) = @_;
return
unless my $file = IO::File->new($fp, 'r');
my($res) = Storable::thaw(${$_F->read($file)});
$req->put($fp => $res);
return $res;
}
sub _try_compute {
my($proto, $fp, $req, $extra) = @_;
my($res);
($_SU ||= b_use('Bivio.ShellUtil'))->lock_action(
sub {
$res = _read_and_thaw($fp, $req) || _compute($proto, $fp, $req, $extra);
return
},
$fp,
1,
);
return $res || $proto->internal_compute_no_cache($req, @$extra);
}
1;