Myco::Entity::Event - a Myco entity class

Myco documentation Contained in the Myco distribution.

Index

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NAME

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Myco::Entity::Event - a Myco entity class

SYNOPSIS

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  use Myco;

  # Constructors. See Myco::Entity for more.
  my $obj = Myco::Entity::Event->new;

  # Accessors.
  my $value = $obj->get_fooattrib;
  $obj->set_fooattrib($value);

  $obj->save;
  $obj->destroy;

DESCRIPTION

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An Event logging class for recording information and history for selected objects

COMMON ENTITY INTERFACE

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Constructor, accessors, and other methods -- as inherited from Myco::Entity.

ATTRIBUTES

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Attributes may be initially set during object construction (with new()) but otherwise are accessed solely through accessor methods. Typical usage:

* Set attribute value
 $obj->set_attribute($value);

Check functions (see Class::Tangram) perform data validation. If there is any concern that the set method might be called with invalid data then the call should be wrapped in an eval block to catch exceptions that would result.

* Get attribute value
 $value = $obj->get_attribute;

A listing of available attributes follows:

kind

 type: int

The kind of the event. Could be 'Create', 'Delete', or 'Modify'

state

 type: perl_dump

A string dump of the Entity at time of Event creation.

entity_id

 type: int

The Tangram ID for the entity.

user_src

 type: ref

The Myco::User object that created (sourced) the entity.

entity_class

 type: string

The name of the class of the entity.

date

 type: rawdate

The date the event was occured.

entity

 type: transient

The entity object about which an event is being recorded. Intitalized with a reference to it.

Myco documentation Contained in the Myco distribution. 
package Myco::Entity::Event;

###############################################################################
# $Id: Event.pm,v 1.5 2006/03/31 19:12:57 sommerb Exp $
#
# See license and copyright near the end of this file.
###############################################################################


##############################################################################
# Dependencies
##############################################################################
# Module Dependencies and Compiler Pragma
use warnings;
use strict;
use Myco::Exceptions;
use Myco::Config qw(:evlog);
use WeakRef;
use Myco::Util::DateTime;
use Tangram::Type::Dump::Perl;

##############################################################################
# Constants
##############################################################################
use constant CREATE => 1;
use constant DELETE => 2;
use constant MODIFY => 3;

our @EXPORT = qw(CREATE DELETE MODIFY);

our $kind_map = { &CREATE => 'Create',
                  &DELETE => 'Delete',
                  &MODIFY => 'Modify', };

##############################################################################
# Private Class Variables
##############################################################################
my $event_cache = {};
sub get_event_cache {
    return $event_cache;
}

my $_enabled = EVLOG;
sub enabled {
    return \$_enabled;
}

my $_classes;
for ( @{+EVLOG_CLASSES} ) {
    $_classes->{$_} = undef;
}
sub classes {
    return $_classes;
}

# Must defer import of constants from Myco::Config  until runtime.
# Workaround for mysterious problem when running under mod_perl (?).
#sub init_constants {
#    Myco::Config->import( qw(:evlog) );
#    $_enabled = EVLOG;
#    for ( @{+EVLOG_CLASSES} ) {
#        $_classes->{$_} = undef;
#    }
#}

##############################################################################
# Inheritance & Introspection
##############################################################################
use base qw(Myco::Entity Exporter);
my $md = Myco::Entity::Meta->new
  ( name => __PACKAGE__,
    tangram => { table => 'entity_event' },
  );

##############################################################################
# Function and Closure Prototypes
##############################################################################
# Use this code reference to validate that a real Myco::User object sourced
# the event
my $chk_user_src = sub {
    my $user_src = $ {$_[0]};
    Myco::Exception::DataValidation->throw
        (error => "$user_src is not a Myco::User object")
          unless UNIVERSAL::isa($user_src, 'Myco::User');
};

# Use this code reference to validate the kind of event
my $chk_kind = sub {
    my $kind = $ {$_[0]};
    Myco::Exception::DataValidation->throwMyco::Entity::Test
        (error => "$kind is not a valid kind of event")
          unless defined $kind_map->{$kind};
};

##############################################################################
# Constructor, etc.
##############################################################################


sub new {
    init_constants() unless defined $_enabled;
    my $invocant = shift;
    my $class = ref $invocant || $invocant;
    my %params = @_;
    my $entity = $params{entity};
    my $entity_class = ref $entity;

    # Handle object event
    my $caching;
    if ($entity_class) {
        if ($_enabled && exists $_classes->{$entity_class}) {
            $caching = 1;
        } else {
            return;
        }
    }

    my $event = $class->SUPER::new(@_);

    if ($caching) {
        my $key = "$entity";
        weaken($event->{entity});
        if (exists $event_cache->{$key}) {
            return $event_cache->{$key};
        } else {
            $event_cache->{$key} = $event;
        }
    }
    return $event;
}

##############################################################################
# Attributes & Attribute Accessors / Schema Definition
##############################################################################


my %kind_map = %$kind_map;
$md->add_attribute( name => 'kind',
                    type => 'int',
                    values => [ keys %kind_map ],
                    value_labels => { %kind_map },
                    tangram_options => { check_func => $chk_kind, },
                  );


$md->add_attribute( name => 'state',
                    type => 'perl_dump',
                    tangram_options => { sql => 'TEXT',
                                         col => 'state' },
                  );




$md->add_attribute( name => 'entity_id',
                    type => 'int', );




# NOTE TO SELF: myco-deploy script was puking on the attribute name: 'user'
$md->add_attribute( name => 'user_src',
                    type => 'ref',
                    tangram_options => { check_func => $chk_user_src,
                                         class => 'Myco::User', },
                  );




$md->add_attribute( name => 'entity_class',
                    type => 'string', );




$md->add_attribute( name => 'date',
                    type => 'rawdate',
                    tangram_options =>
                    { sql => 'DATE',
                      init_default => sub {
                          Myco::Util::DateTime->date('YYYY-MM-DD') },
                    },
                  );




$md->add_attribute( name => 'entity',
                    type => 'transient', );

##############################################################################
# Methods
##############################################################################

sub flush_event {
    my ($class, $entity) = @_;

    my $key = "$entity";
    if ( exists $event_cache->{$key} ) {
        my $event = $event_cache->{$key};

        my $ent_id = $entity->id;
        $event->set_entity_id( $ent_id ) if $ent_id;

        my $id = Myco->insert($event);
        delete $event_cache->{$key} if exists $event_cache->{$key};
        Myco->unload($event);
        return $id;
    }
}

# Method to build up a cache of events.
sub build_event_cache {
    my ($self, $attr, $val) = @_;
    # Exit if we're trying to create an event for an event object
    return if ref $self eq 'Myco::Entity::Event';

    # Treat $val specially if $val is a reference. Just stringify it for now.
    $val = "$val" if ref $val ne '';

    my $event;
    my $key = "$self";
#    if ( exists $event_cache->{$key} ) {
#        $event_cache->{$key}->{$attr} = $val;
#    } else {
#        $event = Myco::Entity::Event->new;
#        $event_cache->{"$event"}->{$attr} = $val;
#        $event_cache->{"$event"}->{$attr} = $val;
#        $event = $self;
#    }

    # Stringify $event for use as a hash key - we'll probably add attrs to it
}

##############################################################################
# Object Schema Activation and Metadata Finalization
##############################################################################
$md->activate_class;

1;
__END__