| [reply]
[d/l] |
Hi,
How are these JSON structures created? If two different objects reference the same (sub-) object instance, how are you going to maintain identity of that sub-object? Maybe the sources of KiokuDB would be interesting to read?
Cheers, Christoph | [reply] |
If you are in control of the deflation of the objects, then I suggest
that you use KiokuDB for this.
{
package Foo;
use Moose; # Not necessary, but advisable
# class definition
}
my $foo = Foo->new;
use KiokuDB;
use feature 'say';
# You can also use a file and an in-memory hash backend instead of DBI
my $db = KiokuDB->new( dsn => 'dbi:SQLite:db=mydb' );
my $scope = $db->new_scope;
# Store the object
my $id = $db->insert($foo);
undef $foo;
# retrieve the object using id lookup
$foo = $db->lookup($id);
say ref $foo; # 'Foo'
You can choose a file backend if you don't want to use a database (although you lose querying capabilities), and you have control over what engine is used to collapse the objects (JSON, Storable, YAML). You get the most speed with Storable, but with JSON and YAML you get readable (and possibly editable) dumps.
It takes a little to learn, but KiokuDB::Tutorial is probably the best place to start.
| [reply]
[d/l] |
If you happen to use Moose, MooseX::Storage supports JSON serialization among others.
I believe the JSON output from object instances are simply a hash/dict with a key "__class__", which is what was previously suggested that you can manually do. The conversion from object to JSON and vice-versa is automatically and easily done for you by the module.
Of course, you can do other tricks as well such as rebuild an entire class tree to/from hashes via Moose's "coercion" features. More importantly, MooseX::Storage also gives you, flexible ways/levels to customize/give hints as to "how" you want your objects serialized/deserialized.
| [reply] |