@namespace("eu.dnetlib.iis.importer.schemas")
protocol IIS{

    record PublicationType {
        boolean article = false;
        boolean dataset = false;
    }

    record DocumentMetadata {
//      document identifier
        string id;
        
//      moved from DocumentBasicMetadata        
//      title
        union { null , string } title = null;
//      abstract or description
        union { null , string } abstract = null;
        union { null , string } language = null;
//      list of keywords (free form)
        union { null , array<string> } keywords = null;
//      alternative identifier (e.g. internal publisher's identifiers)
        union { null , map<string> } externalIdentifiers = null;
//      name of journal in which the article is published
        union { null , string } journal = null;
//      year of publication
        union { null , int } year = null;
//      publisher name
        union { null , string } publisher = null;
//      end of: moved from DocumentBasicMetadata        
//      publication type
        PublicationType publicationType;
        
//      foreign key: Person.id ("raw person" data store)
        union { null , array<string> } authorIds = null;
        
//      identifiers of datasources given document originates from
        union { null , array<string> } datasourceIds = null;
        
    }
    
}