Core API

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EPrints 3 Reference: Directory Structure - Metadata Fields - Repository Configuration - XML Config Files - XML Export Format - EPrints data structure - Core API - Data Objects


API: Core API

The core API was introduced in EPrints 3.2.0 and is intended to provide a clean and consistent programming interface to the EPrints system.

Not all essential functionality is yet available in the new API, as we've only included functions which we are confident we can keep stable for a number of versions.

Overview

 use EPrints;
 my $ep = EPrints->new();
 my $repo = $ep->repository( "myrepo" );
 my $an_eprint = $repo->eprint( 23 );

EPrints

 $ep = EPrints->new();
 @ids = $ep->repository_ids; # list active repository ids
 $repo = $ep->repository( "devel", noise=>1 );
 $repo = $ep->current_repository(); # from Apache::Request URI
 EPrints->abort( $message );

Repository

$xml = $repo->xml;
$dataset = $repo->dataset( "user" );
$user = $repo->current_user;
$query = $repo->query;
$current_page_url = $repo->current_url( host => 1, path => 1, query => 1, etc. );
$config_element = $repo->config( $key, [@subkeys] );
$repository->log( $message ); 
$string = $repo->query->param( "X" );
$repo->redirect( $url );
$eprint = $repo->eprint( 23 );
$user = $repo->user( 23 );
$user = $repo->user_by_username( "cjg" );
$user = $repo->user_by_email( 'cjg@ecs.soton.ac.uk' );

Dataset

 $dataset = $repo->dataset( "eprint" )
 $string = $dataset->base_id; # eprint
 $string = $dataset->id; # inbox
 
 $repo = $dataobj->repository;
 
 $dataobj = $dataset->create_dataobj( $data );
 $eprint = $dataset->dataobj( 23 );
 
 %options = (filters => [ { meta_fields => [ 'contributors_id' ], value => "13249", match=>"EX" } ]);
 $search = $dataset->prepare_search( %options );
 $list = $dataset->search( %options ); # prepare_search( %options )->execute
 $list = $dataset->search; # match ALL
 
 $metafield = $dataset->field( $fieldname );
 $metafield = $dataset->key_field;
 @metafields = $dataset->fields; 
 
 $dataset->search->map( sub {}, $ctx );
 $n = $dataset->search->count; 
 $ids = $dataset->search->ids;
 $list = $dataset->list( \@ids );

list

 $n = $list->count;
 $list->map( sub {
     my ( $repository, $dataset, $dataobj, $ctx ) = @_;
     # do something to the dataobj here
 }, $ctx );
 $dataobj = $list->item( $offset );
 @all_dataobjs = $list->slice 
 @dataobjs = $list->slice( $offset, $length ); 
 \@ids = $list->ids;

XML

 $doc = $xml->parse_string( $string );
 $doc = $xml->parse_file( $filename );
 $doc = $xml->parse_url( $url );
 
 $utf8_string = $xml->to_string( $dom_node, %opts );
 
 $dom_node = $xml->clone( $dom_node ); # deep
 $dom_node = $xml->clone_node( $dom_node ); # shallow
 
 $dom_node = $xml->contents_of( $dom_node ); # clone and return child nodes
 $utf8_string = $xml->text_contents_of( $dom_node ); # Return text child nodes as a string
 
 $dom_node = $xml->create_element( $name, %attr );
 $dom_node = $xml->create_text_node( $value );
 $dom_node = $xml->create_comment( $value );
 $dom_node = $xml->create_document_fragment;
 
 $bool = $xml->is( $dom_node, "Text" );
 
 $xml->dispose( $dom_node );

XHTML

 $xhtml = $repo->xhtml;
 
 $utf8_string = $xhtml->to_xhtml( $dom_node, %opts ); # remove NS prefixes, fix <script> etc.
 
 $xhtml_dom_node = $xhtml->input_field( $name, $value, %opts ); # nb. type & noenter are now options. noenter prevents the enter being pressed in the input field using javascript
 $xhtml_dom_node = $xhtml->hidden_field( $name, $value, %opts ); # tdb: this is used *a lot* and is well defined
 $xhtml_dom_node = $xhtml->text_area_field( $name, $value, %opts ); # tdb: value becomes a child text node 
 $xhtml_dom_node = $xhtml->form( $method, $url );
 
 $xhtml_dom_node = $xhtml->data_element( $name, $value, %opts ); # tdb: render_data_element
 
 $page = $xhtml->page( $map, %opts );

Page

 $page->send( %options ); 
 $page->write_to_file( $filename );

DataObj

 $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 );

MetaField

Now has a handle on both it's repository/session AND dataset.

 my $field = $dataset->field( $fieldname );
 
 $dataset = $field->dataset;
 $repo = $field->repository;
 
 $field->set_property( $property, $value );
 $value = $field->property( $property );
 
 $name = $field->name;
 $type = $field->type;
 
 $xhtml = $field->render_name;
 $xhtml = $field->render_help;
 $xhtml = $field->render_value_label( $value );
 
 $values = $field->all_values( %opts );
 $sorted_list = $field->sort_values( $unsorted_list );