/
DataObj.pm
2513 lines (1787 loc) · 53 KB
/
DataObj.pm
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######################################################################
#
# EPrints::DataObj
#
######################################################################
#
#
######################################################################
=pod
=for Pod2Wiki
=head1 NAME
B<EPrints::DataObj> - Base class for records in EPrints.
=head1 SYNOPSIS
$dataobj = $dataset->dataobj( $id );
$dataobj->delete;
$dataobj->commit( $force );
$dataset = $dataobj->dataset;
$repo = $dataobj->repository;
$id = $dataobj->id;
$dataobj->set_value( $fieldname, $value );
$value = $dataobj->value( $fieldname );
\@value = $dataobj->value( $fieldname ); # multiple
$boolean = $dataobj->is_set( $fieldname );
$xhtml = $dataobj->render_value( $fieldname );
$xhtml = $dataobj->render_citation( $style, %opts );
$uri = $dataobj->uri;
$url = $dataobj->url;
$string = $dataobj->export( $plugin_id, %opts );
$dataobj = $dataobj->create_subobject( $fieldname, $epdata );
=head1 DESCRIPTION
This module is a base class which is inherited by L<EPrints::DataObj::EPrint>,
L<EPrints::DataObj::User>, L<EPrints::DataObj::Subject> and
L<EPrints::DataObj::Document> and several other classes.
It is ABSTRACT - its methods should not be called directly.
=cut
######################################################################
#
# INSTANCE VARIABLES:
#
# $self->{data}
# A reference to a hash containing the metadata of this
# record.
#
# $self->{session}
# The current EPrints::Session
#
# $self->{dataset}
# The EPrints::DataSet to which this record belongs.
#
######################################################################
package EPrints::DataObj;
use MIME::Base64 ();
use strict;
######################################################################
=pod
=begin InternalDoc
=item $sys_fields = EPrints::DataObj->get_system_field_info
Return an array describing the system metadata of the this
dataset.
=end InternalDoc
=cut
######################################################################
sub get_system_field_info
{
my( $class ) = @_;
return ();
}
######################################################################
=pod
=begin InternalDoc
=item $dataobj = EPrints::DataObj->new( $session, $id [, $dataset] )
Return new data object, created by loading it from the database.
If $dataset is not defined uses the default dataset for this object.
=end InternalDoc
=cut
######################################################################
sub new
{
my( $class, $session, $id, $dataset ) = @_;
if( !defined($dataset) )
{
$dataset = $session->dataset( $class->get_dataset_id );
}
return $session->get_database->get_single(
$dataset,
$id );
}
######################################################################
=pod
=begin InternalDoc
=item $dataobj = EPrints::DataObj->new_from_data( $session, $data [, $dataset ] )
Construct a new EPrints::DataObj object based on the $data hash
reference of metadata.
Used to create an object from the data retrieved from the database.
=end InternalDoc
=cut
######################################################################
sub new_from_data
{
my( $class, $session, $data, $dataset ) = @_;
my $self = { data=>{}, changed=>{}, non_volatile_change=>0 };
$self->{session} = $session;
Scalar::Util::weaken($self->{session})
if defined &Scalar::Util::weaken;
if( defined( $dataset ) )
{
$self->{dataset} = $dataset;
}
else
{
$self->{dataset} = $session->dataset( $class->get_dataset_id );
}
bless( $self, ref($class) || $class );
if( defined $data )
{
if( $self->{dataset}->confid eq "eprint" )
{
$self->set_value( "eprint_status", $data->{"eprint_status"} );
}
foreach( keys %{$data} )
{
# this will cause an error if the field is unknown
$self->set_value( $_, $data->{$_} );
}
}
return( $self );
}
sub clone
{
my( $self ) = @_;
my $session = $self->{session};
my $clone = $self->create_from_data( $session, $self->get_data, $self->get_dataset );
return $clone;
}
######################################################################
#=pod
#
#=item $dataobj = EPrints::DataObj::create( $session, @default_data )
#
#ABSTRACT.
#
#Create a new object of this type in the database.
#
#The syntax for @default_data depends on the type of data object.
#
#=cut
#######################################################################
sub create
{
my( $session, @default_data ) = @_;
Carp::croak( "EPrints::DataObj::create must be overridden" );
}
######################################################################
#=pod
#
#=item $dataobj = EPrints::DataObj->create_from_data( $session, $data, $dataset )
#
#Create a new object of this type in the database.
#
#$dataset is the dataset it will belong to.
#
#$data is the data structured as with new_from_data.
#
#This will create sub objects also.
#
#Call this via $dataset->create_object( $session, $data )
#
#=cut
######################################################################
sub create_from_data
{
my( $class, $session, $data, $dataset ) = @_;
$data = EPrints::Utils::clone( $data );
$dataset ||= $session->dataset( $class->get_dataset_id );
# <document id="/xx" />
delete $data->{_id};
# If there is a field which indicates the virtual dataset,
# set that now, so it's visible to get_defaults.
my $ds_id_field = $dataset->get_dataset_id_field;
if( defined $ds_id_field )
{
$data->{$ds_id_field} = $dataset->id;
}
# get defaults modifies the hash so we must copy it.
my $defaults = EPrints::Utils::clone( $data );
$defaults = $class->get_defaults( $session, $defaults, $dataset );
# cache the configuration options in variables
my $migration = $session->config( "enable_import_fields" );
my @create_subdataobjs;
FIELD: foreach my $field ( $dataset->fields )
{
my $fieldname = $field->name;
# strip sub-objects and create them once we exist
if( $field->isa( "EPrints::MetaField::Subobject" ) )
{
push @create_subdataobjs, [ $field, delete $data->{$fieldname} ]
if defined $data->{$fieldname};
next FIELD;
}
if( !$field->property( "import" ) && !$migration )
{
delete $data->{$fieldname};
}
if( !EPrints::Utils::is_set( $data->{$fieldname} ) )
{
$data->{$fieldname} = $defaults->{$fieldname}
if exists $defaults->{$fieldname};
}
}
my $self = $class->new_from_data( $session, $data, $dataset );
return undef unless defined $self;
# this checks whether the object exists
my $rc = $session->get_database->add_record( $dataset, $self->get_data );
return undef unless $rc;
$self->set_under_construction( 1 );
# create sub-dataobjs
for(@create_subdataobjs)
{
my $field = $_->[0];
$_->[1] = [$_->[1]] if ref($_->[1]) ne 'ARRAY';
my @dataobjs;
my %id_map;
foreach my $epdata (@{$_->[1]})
{
my $dataobj = $self->create_subdataobj( $field->name, $epdata );
if( !defined $dataobj )
{
# next; # uncomment to still import doc metadata even if the download failed
Carp::carp( $dataset->base_id.".".$self->id." failed to create subdataobj on ".$dataset->id.".".$field->name . " (See DataObj:create_from_data to override)");
$self->remove();
return undef;
}
push @dataobjs, $dataobj;
$id_map{$epdata->{_id}} = $dataobj->internal_uri
if defined $epdata->{_id};
}
foreach my $dataobj (@dataobjs)
{
next if !$dataobj->exists_and_set( "relation_uri" );
my $value = $dataobj->value( "relation_uri" );
$value = EPrints::Utils::clone( $value );
foreach my $v (@$value)
{
$v = $id_map{$v} if exists $id_map{$v};
}
$dataobj->set_value( "relation_uri", $value );
$dataobj->commit;
}
$self->set_value( $field->name, $field->property( "multiple" ) ? \@dataobjs : $dataobjs[0] );
}
if( $migration && $dataset->key_field->isa( "EPrints::MetaField::Counter" ) )
{
$session->get_database->counter_minimum(
$dataset->key_field->property( "sql_counter" ),
$self->id
);
}
$self->set_under_construction( 0 );
# queue all the fields for indexing.
$self->queue_all;
return $self;
}
=begin InternalDoc
=item $dataobj = $dataobj->create_subdataobj( $fieldname, $epdata )
Creates and returns a new dataobj that is a sub-object of this object in field $fieldname with initial data $epdata.
Clears the sub-object cache for this $fieldname which is equivalent to:
$dataobj->set_value( $fieldname, undef );
=end InternalDoc
=cut
sub create_subdataobj
{
my( $self, $fieldname, $epdata ) = @_;
my $field = $self->dataset->field( $fieldname );
if( !defined $field )
{
EPrints::abort( "Cannot create sub-object on non-existent field $fieldname" );
}
if( !$field->isa( "EPrints::MetaField::Subobject" ) )
{
EPrints::abort( "Cannot create sub-object on non-subobject field $fieldname" );
}
# sub-objects cache is now out of date
delete $self->{data}->{$fieldname};
my $dataset = $self->repository->dataset( $field->property( "datasetid" ) );
$epdata->{_parent} = $self;
# work-around for Document expecting "eprintid" to be set as well as _parent
if( $self->isa( "EPrints::DataObj::EPrint" ) && $fieldname eq "documents" )
{
$epdata->{eprintid} = $self->id;
}
return $dataset->create_dataobj( $epdata );
}
######################################################################
=pod
=begin InternalDoc
=item $defaults = EPrints::User->get_defaults( $session, $data, $dataset )
Return default values for this object based on the starting data.
Should be subclassed.
=end InternalDoc
=cut
######################################################################
sub get_defaults
{
my( $class, $session, $data, $dataset ) = @_;
if( !defined $dataset )
{
$dataset = $session->dataset( $class->get_dataset_id );
}
my $migration = $session->config( "enable_import_fields" );
# set any values that a field has a default for e.g. counters
foreach my $field ($dataset->get_fields)
{
next if defined $field->get_property( "sub_name" );
# avoid getting a default value if it's already set
next if
EPrints::Utils::is_set( $data->{$field->name} ) &&
($field->property( "import") || $migration);
my $value = $field->get_default_value( $session );
next unless EPrints::Utils::is_set( $value );
$data->{$field->get_name} = $value;
}
my $old_default_fn = "set_".$class->get_dataset_id."_defaults";
if( $session->can_call( $old_default_fn ) )
{
$session->call(
$old_default_fn,
$data,
$session,
$data->{_parent} );
}
return $data;
}
# Update all the stuff that needs to be updated before
# an object is written to the database.
sub update_triggers
{
my( $self ) = @_;
my $old_auto_fn = "set_".$self->get_dataset_id."_automatic_fields";
if( $self->{session}->can_call( $old_auto_fn ) )
{
$self->{session}->call( $old_auto_fn, $self );
}
}
######################################################################
=pod
=over 4
=item $success = $dataobj->delete
Delete this data object from the database and any sub-objects or related files.
Return true if successful.
=cut
######################################################################
sub delete { shift->remove( @_ ) }
sub remove
{
my( $self ) = @_;
$self->{dataset}->run_trigger( EPrints::Const::EP_TRIGGER_REMOVED,
dataobj => $self,
);
$self->queue_removed;
return $self->{session}->get_database->remove(
$self->{dataset},
$self->get_id );
}
=item $dataobj->empty()
Remove all of this object's values that may be imported.
=cut
sub empty
{
my( $self ) = @_;
foreach my $field ($self->dataset->fields)
{
next if $field->is_virtual;
next if !$field->property( "import" );
$field->set_value( $self, $field->property( "multiple" ) ? [] : undef );
}
}
=item $dataobj->update( $epdata [, %opts ] )
Update this object's values from $epdata. Ignores any values that do not exist in the dataset or do not have the 'import' property set.
include_subdataobjs - replace sub-dataobjs if given
# replaces all documents in $dataobj
$dataobj->update( {
title => "Wombats on Fire",
documents => [{
main => "wombat.pdf",
...
}],
}, include_subdataobjs => 1 );
=cut
sub update
{
my( $self, $epdata, %opts ) = @_;
my $dataset = $self->{dataset};
foreach my $name (keys %$epdata)
{
next if $name =~ /^_/;
next if !$dataset->has_field( $name );
my $field = $dataset->field( $name );
next if !$field->property( "import" ) && !$self->{session}->config( "enable_import_fields" );
if( $field->isa( "EPrints::MetaField::Subobject" ) )
{
next if !$opts{include_subdataobjs};
local $_;
my $v = $field->get_value( $self );
for($field->property( "multiple" ) ? @$v : $v)
{
$_->remove if defined $_;
}
$v = $epdata->{$field->name};
for($field->property( "multiple" ) ? @{$v} : $v)
{
next if !defined $_;
$self->create_subdataobj( $field->name, $_ );
}
}
else
{
$field->set_value( $self, $epdata->{$name} );
}
}
}
# $dataobj->set_under_construction( $boolean )
#
# Set a flag to indicate this object is being constructed and
# any house keeping will be handled by the method constructing it
# so don't do it elsewhere
sub set_under_construction
{
my( $self, $boolean ) = @_;
$self->{under_construction} = $boolean;
}
# $boolean = $dataobj->under_construction
#
# True if this object is part way through being constructed.
sub under_construction
{
my( $self ) = @_;
return $self->{under_construction};
}
######################################################################
=pod
=begin InternalDoc
=item $dataobj->clear_changed( )
Clear any changed fields, which will result in them not being committed unless
force is used.
This method is used by the Database to avoid unnecessary commits.
=end InternalDoc
=cut
######################################################################
sub clear_changed
{
my( $self ) = @_;
$self->{non_volatile_change} = 0;
$self->{changed} = {};
}
######################################################################
=pod
=item $success = $dataobj->commit( [$force] )
Write this object to the database and reset the changed fields.
If $force isn't true then it only actually modifies the database
if one or more fields have been changed.
Commit may also queue indexer jobs or log changes, depending on the object.
=cut
######################################################################
sub commit
{
my( $self, $force ) = @_;
if( scalar( keys %{$self->{changed}} ) == 0 )
{
# don't do anything if there isn't anything to do
return( 1 ) unless $force;
}
# Remove empty slots in multiple fields
$self->tidy;
$self->dataset->run_trigger( EPrints::Const::EP_TRIGGER_BEFORE_COMMIT,
dataobj => $self,
changed => $self->{changed},
);
# Write the data to the database
my $success = $self->{session}->get_database->update(
$self->{dataset},
$self->{data},
$force ? $self->{data} : $self->{changed} );
if( !$success )
{
my $db_error = $self->{session}->get_database->error;
$self->{session}->get_repository->log(
"Error committing ".$self->get_dataset_id.".".
$self->get_id.": ".$db_error );
return 0;
}
# Queue changes for the indexer (if indexable)
$self->queue_changes();
$self->dataset->run_trigger( EPrints::Const::EP_TRIGGER_AFTER_COMMIT,
dataobj => $self,
changed => $self->{changed},
);
# clear changed fields
$self->clear_changed();
return $success;
}
######################################################################
=pod
=item $value = $dataobj->value( $fieldname )
Get a the value of a metadata field. If the field is not set then it returns
undef unless the field has the property multiple set, in which case it returns
[] (a reference to an empty array).
=cut
######################################################################
sub value { shift->get_value( @_ ) }
sub get_value
{
my( $self, $fieldname ) = @_;
my $field = $self->{dataset}->field( $fieldname );
if( !defined $field )
{
EPrints::abort( "Attempt to get value from not existent field: ".$self->{dataset}->id()."/$fieldname" );
}
my $r = $field->get_value( $self );
unless( EPrints::Utils::is_set( $r ) )
{
if( $field->get_property( "multiple" ) )
{
return [];
}
else
{
return undef;
}
}
return $r;
}
sub get_value_raw
{
my( $self, $fieldname ) = @_;
EPrints::abort( "\$fieldname undefined in get_value_raw" ) unless defined $fieldname;
return $self->{data}->{$fieldname};
}
######################################################################
=pod
=item $dataobj->set_value( $fieldname, $value )
Set the value of the named metadata field in this record.
=cut
######################################################################
sub set_value
{
my( $self, $fieldname, $value ) = @_;
if( !$self->{dataset}->has_field( $fieldname ) )
{
if( $self->{session}->get_noise > 0 )
{
Carp::carp( "Attempt to set value on not existent field: ".$self->{dataset}->id().".$fieldname" );
}
return;
}
my $field = $self->{dataset}->get_field( $fieldname );
$field->set_value( $self, $value );
}
sub set_value_raw
{
my( $self , $fieldname, $value ) = @_;
if( !defined $self->{changed}->{$fieldname} )
{
# if it's already changed once then we don't
# want to fiddle with it again
if( !_equal( $self->{data}->{$fieldname}, $value ) )
{
$self->{changed}->{$fieldname} = $self->{data}->{$fieldname};
my $field = $self->{dataset}->get_field( $fieldname );
if( !$field->property( "volatile" ) )
{
$self->{non_volatile_change} = 1;
}
}
}
$self->{data}->{$fieldname} = $value;
}
# internal function
# used to see if two data-structures are the same.
sub _equal
{
my( $a, $b ) = @_;
# both undef is equal
if( !EPrints::Utils::is_set($a) && !EPrints::Utils::is_set($b) )
{
return 1;
}
# one xor other undef is not equal
if( !EPrints::Utils::is_set($a) || !EPrints::Utils::is_set($b) )
{
return 0;
}
# simple value
if( ref($a) eq "" )
{
return( $a eq $b );
}
if( ref($a) eq "ARRAY" )
{
# different lengths?
return 0 if( scalar @{$a} != scalar @{$b} );
for(my $i=0; $i<scalar @{$a}; ++$i )
{
return 0 unless _equal( $a->[$i], $b->[$i] );
}
return 1;
}
if( ref($a) eq "HASH" )
{
my @akeys = sort keys %{$a};
my @bkeys = sort keys %{$b};
# different sizes?
# return 0 if( scalar @akeys != scalar @bkeys );
# not testing as one might skip a value, the other define it as
# undef.
my %testk = ();
foreach my $k ( @akeys, @bkeys ) { $testk{$k} = 1; }
foreach my $k ( keys %testk )
{
return 0 unless _equal( $a->{$k}, $b->{$k} );
}
return 1;
}
Carp::cluck( "Warning: can't compare $a and $b" );
return 0;
}
######################################################################
=pod
=item @values = $dataobj->get_values( $fieldnames )
Returns a list of all the values in this record of all the fields specified
by $fieldnames. $fieldnames should be in the format used by browse views - slash
seperated fieldnames with an optional .id suffix to indicate the id part rather
than the main part.
For example "author.id/editor.id" would return a list of all author and editor
ids from this record.
=cut
######################################################################
sub get_values
{
my( $self, $fieldnames ) = @_;
my %seen;
my @values;
foreach my $fieldname ( split( "/" , $fieldnames ) )
{
my $field = EPrints::Utils::field_from_config_string(
$self->{dataset}, $fieldname );
my $value = $field->get_value( $self );
$value = [$value] if ref($value) ne 'ARRAY';
foreach my $v (@$value)
{
next if $seen{$field->get_id_from_value( $self->{session}, $v )}++;
push @values, $v;
}
}
return @values;
}
######################################################################
=pod
=begin InternalDoc
=item $session = $dataobj->get_session
Returns the EPrints::Repository object to which this record belongs.
=end InternalDoc
=cut
######################################################################
sub repository { shift->get_session(@_) }
sub get_session
{
my( $self ) = @_;
return $self->{session};
}
######################################################################
=pod
=begin InternalDoc
=item $data = $dataobj->get_data
Returns a reference to the hash table of all the metadata for this record keyed
by fieldname.
=end InternalDoc
=cut
######################################################################
sub get_data
{
my( $self ) = @_;
return $self->{data};
}
######################################################################
=pod
=begin InternalDoc
=item $dataset = EPrints::DataObj->get_dataset_id
Returns the id of the L<EPrints::DataSet> object to which this record belongs.
=end InternalDoc
=cut
######################################################################
sub get_dataset_id
{
my( $class ) = @_;
Carp::croak( "get_dataset_id must be overridden by $class" );
}
######################################################################
=pod
=begin InternalDoc
=item $dataset = $dataobj->get_dataset
Returns the L<EPrints::DataSet> object to which this record belongs.
=end InternalDoc
=cut
######################################################################
sub dataset { shift->get_dataset( @_ ) }
sub get_dataset
{
my( $self ) = @_;
return $self->{dataset};
}
######################################################################
=pod
=item $bool = $dataobj->is_set( $fieldname )
Returns true if the named field is set in this record, otherwise false.
Warns if the field does not exist.
=cut
######################################################################
sub is_set
{
my( $self, $fieldname ) = @_;
if( !$self->{dataset}->has_field( $fieldname ) )
{
$self->{session}->get_repository->log(
"is_set( $fieldname ): Unknown field" );
}
my $value = $self->get_value( $fieldname );
return EPrints::Utils::is_set( $value );
}
######################################################################