Talk:API:EPrints

I'm going to use this page to get my thoughts in order. Cjg 16:58, 2 September 2009 (BST)

Current 3.1 System

Unsessioned Classes

These classes don't store a session internally resulting in methods like $foo->render( $session, ARGS ).

• Repository
• DataSet
• MetaField
• Language

Sessioned Classes

These classes store a session internally resulting in methods like $foo->render( ARGS ).

• Session
• DataObj
• Plugin
• List
• Search
• Database
• Workflow
• ScreenProcessor

API

New Plan(!)

• Merge Session and Repository into a single class.
• Move XML functions into their own class.
• Move Page functions into their own class.
• Add a link to repository for dataset and metafield.
• Ensure cleanup when repository object goes out of scope.
• Make EPrints->new() return an eprints object which can pass out repository objects.
  • repository objects don't have a link to the EPrints object EVER.
  • When the eprints object is DESTROY'd it takes out the repositories, datasets and metafields etc.

EPrints

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

repo

Yes:

$xml = $repo->xml;
$dataset = $repo->dataset( "user" );
$user = $repo->current_user;
$query = $repo->query;
$current_page_url = $repo->current_url; 
$config_element = $repo->config( $key, [@subkeys] );
$repository->log( $message ); 
$string = $repo->query->param( "X" );
$repo->redirect( $url );

Maybe:

• tdb: language accessors
  • cjg: I think thses don't belong in the API - why do people need access to them? If I'm wrong we add them in API 1.1?

$lang = $repo->language( $langid );
$lang = $repo->default_language; # needed? nee ->language( undef )
$lang = $repo->current_language;

• cjg: I think these would be very useful but they are inconsistent.

$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

$string = $dataset->base_id; # eprint
$string = $dataset->id; # inbox
$dataobj = $datasset->create_dataobj( $data );
$user = $dataset->dataobj( 23 );

$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;

Maybe:

• tdb: is this common enough to replace EPrints::List->new()?
  • cjg: part of the API goal IMO is to get away from classnames if at all possible, so this would become the proper way to create a list object.

$list = $dataset->list( \@ids ); 

Maybe not:

$bool = $dataset->has_field( $fieldname ); 

list

$n = $list->count();
$list->map( sub {}, $ctx );
$dataobj = $list->item( offset );
@dataobjs = $list->slice( offset, length ); 
@ids = $list->ids;

search

$search = $dataset->prepare_search( order => "-date", satisfy_all=>1 );
$search = $dataset->prepare_search( query => [], filters => [], ... );

$list = $search->execute();

# the below call needs replacing with something less sucky.
$search->add_term( %opts ); # better name needed?
$search->add_term( $ds->get_field( "type" ), qw/ article book /, "EQ", "ANY" );

Alternatives

I would like to make the value argument not automagically-split on ANY but explicitly use an array ref of values to match.

my $s = $dataset->prepare_search( order => "-date", satisfy_all => 1, query => [
 { fields => ["type"], values => [qw/article book/], merge => EPrints::Search::ANY },
 { fields => [qw( title abstract )], values => ["dogbert dilbert"], match => EPrints::Search::INDEX, merge => EPrints::Search::ALL },
 { fields => ["userid"], values => ["52"], match => EPrints::Search::EXACT },
] );
my $s = $dataset->prepare_search( order => "-date", satisfy_all => 1 );
$s->add_query( ["type"], [qw/article book/], merge => EPrints::Search::ANY );
$s->add_query( [qw( title abstract )], ["dogbert dilbert"], match => EPrints::Search::INDEX, merge => EPrints::Search::ALL );
$s->add_query( ["userid"], ["52"], match => EPrints::Search::EXACT );
my $list = $s->execute;

$s->add_query( [$dataset->get_field( "type" )], [qw/ article book/], merge => EPrints::Search::ANY );

print $list->count, "\n";

• Cjg 18:27, 16 September 2009 (BST) : I kinda like where this is going but don't like the ugly constants.

XML

$doc = $xml->parse_string( $string );
$doc = $xml->parse_file( $filename );
$doc = $xml->parse_url( $url );

$utf8_string = $xml->to_string( $dom_node, %opts ); 
$utf8_string = $xml->to_plain_text( $dom_node, %opts ); # nee tree_to_utf8
$utf8_string = $xml->to_xhtml( $dom_node, %opts ); # remove NS prefixes, fix <script> etc.
$utf8_string = $xml->text_content( $dom_node ); # textual content?

$dom_node = $xml->clone( $dom_node ); # deep
$dom_node = $xml->clone_node( $dom_node ); # shallow

$dom_node = $xml->create_element( $name, %attr );
$dom_node = $xml->create_text_node( $value );
$dom_node = $xml->create_comment_node( $value );
$dom_node = $xml->create_document_fragment;

$xml->dispose( $dom_node );

$page = $xml->build_page( %opts );

$xhtml_dom_node = $xml->html_phrase( $phrase_id );
$utf8string = $xml->text_phrase( $phrase_id );

# tdb: move these to EPrints::XHTML and strip ^render_?
$xhtml_dom_node = $xml->render_ruler;
$xhtml_dom_node = $xml->render_nbsp;
$xhtml_dom_node = $xml->render_link( $url, %opts ); #nb will require clever hack if scalar @opts = 1;
$xhtml_dom_node = $xml->render_name( $namehash, render_order=>"gf" ); # or fg 
$xhtml_dom_node = $xml->render_input_field( %opts ); # nb. noenter & hidden are now options.
$xhtml_dom_node = $xml->render_form( $method, $url );

Could we shorten this to $xml->ruler $xml->text etc...?

Page

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

Current

my $field = $dataset->get_field( $fieldname );

# you must clone a field to modify any properties
$newfield = $field->clone;
$newfield->set_property( $property, $value );

$name = $field->get_name;
$type = $field->get_type;
$value = $field->get_property( $property );
$boolean = $field->is_type( @typenames );
$results = $field->call_property( $property, @args ); 
# (results depend on what the property sub returns)

$xhtml = $field->render_name( $handle );
$xhtml = $field->render_help( $handle );
$xhtml = $field->render_value( $handle, $value, $show_all_langs, $dont_include_links, $object );
$xhtml = $field->render_single_value( $handle, $value );
$xhtml = $field->get_value_label( $handle, $value );

$values = $field->get_values( $handle, $dataset, %opts );

$sorted_list = $field->sort_values( $handle, $unsorted_list );

nherrits all methods from EPrints::DataObj.

# create a new document on $eprint 
my $doc_data = {
  _parent => $eprint,
  eprintid => $eprint->get_id,
};
my $doc_ds = $handle->get_dataset( 'document' );
my $document = $doc_ds->create_object( $handle, $doc_data );

# Add files to the document  
$success = $doc->add_file( $file, $filename, [$preserve_path] );
$success = $doc->upload( $filehandle, $filename [, $preserve_path [, $filesize ] ] );
$success = $doc->upload_archive( $filehandle, $filename, $archive_format );
$success = $doc->add_archive( $file, $archive_format );
$success = $doc->add_directory( $directory );
$success = $doc->upload_url( $url );

# get an existing document
$document = $handle->get_document( $doc_id );
# or
foreach my $doc ( $eprint->get_all_documents ) { ... }

# eprint to which this document belongs
$eprint = $doc->get_eprint;

# delete a document object *forever*:
$success = $doc->remove;

$url = $doc->get_url( [$file] );
$path = $doc->local_path;
%files = $doc->files;

# delete a file
$success = $doc->remove_file( $filename );
# delete all files
$success = $doc->remove_all_files;

# change the file which is used as the URL for the document.
$doc->set_main( $main_file );

# icons and previews
$xhtml = $doc->render_icon_link( %opts );
$xhtml = $doc->render_preview_link( %opts );