afs_rdfa_extract - AFS - Reference Guides

AFS Filters Description

Product
AFS
AFS_Version
7.12
Category
Reference Guides
language
English

RDFa Extract filter allows to extract RDFa graph from an HTML page.

The filter is declared with the afs_rdfa_extract type. It is in the antidot-paf-rdf package. It is a processor filter.

This filter can be instantiated only once at any given moment. It will not read the "instances" parameter in the configuration.

The RDFa Extract filter specifications are described in the following table:

Parameter name

Mandatory

Type

Default

Description

input_layer

No

layer

CONTENTS

It is the input layer.

output_layer

No

layer

RDF

It is the output layer.

rdfa_subject_layer

No

layer

N/A

If set, the filter adds a triple in this layer for every processed document. In this triple, subject is the document URI, predicate is the "rdf:type" and object is http://ref.antidot.net/v7/afs#webOrigin. Document uri MUST be UTF-8 compliant, otherwise filter will fail to produce this triple.

Note: Note on rdfa_subject_layer parameter: in some cases, there is no simple way to extract the main uri which represents the data. Then, the purpose of the rdfa_subject_layer parameter is to create a specific triple which uses the uri of the PaF document, as following (written in N3): <http://test.com/test> a <http://ref.antidot.net/v7/afs#webOrigin>. where http://test.com/test is replaced by the uri of the current document.