ObjStore::ServerDB - Generic Real-Time Database Server Framework

ObjStore documentation Contained in the ObjStore distribution.

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NAME

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ObjStore::ServerDB - Generic Real-Time Database Server Framework

SYNOPSIS

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    osperlserver host:/full/path/to/db+=MyClass

DESCRIPTION

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An active database is an framework for tightly integrated collaboration. While implementation abstraction is preserved without hinderance, objects can easy interact in a variety of ways:

* ABSTRACTION / COLLABORATION

The hash at the top of the database holds the set of cooperating objects that implement all database functionality. This hash is always accessable via $any-database_of->hash>. Furthermore, keys are populated such that they reflect the @ISA tree of object instances.

* CLIENT / SERVER

Other processes can read the database asyncronously with MVCC transactions invoke remote method invokations (RMIs) on individual objects. See ObjStore::notify.

* EVENT MANAGEMENT

The Event API is fully integrated (see ObjStore::Process). Moreover, low priority jobs can be (persistently) queued for processing with a variety of scheduling options (see ObjStore::Job).

BOOTSTRAPPING

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The $db-hash->do_boot_class> method creates arbitrary classes and populates the top-level hash. There are quite a few ways to invoke it:

* COMMAND-LINE
  osperlserver host:/full/path/to/db+=MyClass
* RMI
  $db->hash->boot_class('MyClass');
* INHERITANCE
  package MyDB::Top;
  require 'ObjStore::ServerDB';
  use base 'ObjStore::ServerDB::Top';
  sub boot {
     my ($o) = @_;
     $o->boot_class('MyClass');
  }

  osperlserver host:/full/path/to/db=MyDB
ObjStore documentation Contained in the ObjStore distribution. 
use strict;
package ObjStore::ServerDB;
use Carp;
use ObjStore ':ADV';
use Carp;
use base 'ObjStore::HV::Database';
use vars qw($VERSION);
$VERSION = '0.05';
require ObjStore::ServerDB::Top;

sub fork_server {
    carp "EXPERIMENTAL";
    my ($o,$path) = @_;
    $path ||= $o->get_pathname() if ref $o;
    my $class = ref $o || $o;
    my $srv = 'osperlserver';
    my $cmd;
    if (grep /blib/, @INC) {
	if (-x "./blib/script/$srv") {
	    # ?XXX never used?
	    $cmd = "$^X -Mblib ./blib/script/$srv -F $path &";
	} else {
	    $cmd = "$srv -Mblib -F $path &";
	}
    } else {
	$cmd = "$srv $path=$class";
    }
#    warn $cmd;
    system $cmd;
}

sub new {
    my ($class,$path,$mode,$mask) = @_;
    $mode ||= 'mvcc';
    $mask = $mode eq 'update'? 0666 : 0 unless defined $mask;

    # trap not_found errors? XXX
    ObjStore::open($path, $mode, $mask);
}

1;