def map_metadata
      metadata = {}
      metadata['@context'] = ROF::RdfContext.dup
      # metdata derived from project ttl file
      metadata['dc:created'] = Time.iso8601(ttl_data[0][@osf_map['dc:created']][0]['@value']).to_date.iso8601 + 'Z'
      metadata['dc:title'] = ttl_data[0][@osf_map['dc:title']][0]['@value']
      metadata['dc:description'] = ttl_data[0][@osf_map['dc:description']][0]['@value']
      metadata['dc:subject'] = map_subject
      # metadata derived from osf_projects data, passed from UI
      metadata['dc:source'] = 'https://osf.io/' + source_slug
      metadata['dc:creator#adminstrative_unit'] = project['administrative_unit']
      metadata['dc:creator#affiliation'] = project['affiliation']
      metadata['nd:osfProjectIdentifier'] = osf_project_identifier
      metadata['dc:creator'] = map_creator
      metadata['dc:type'] = project['package_type']
      metadata
    end
def map_metadata
      metadata = {}
      metadata['@context'] = ROF::RdfContext.dup
      # metdata derived from project ttl file
      metadata['dc:created'] = Time.iso8601(ttl_data[0][@osf_map['dc:created']][0]['@value']).to_date.iso8601 + 'Z'
      metadata['dc:title'] = ttl_data[0][@osf_map['dc:title']][0]['@value']
      metadata['dc:description'] = ttl_data[0][@osf_map['dc:description']][0]['@value']
      metadata['dc:subject'] = map_subject
      # metadata derived from osf_projects data, passed from UI
      metadata['dc:source'] = 'https://osf.io/' + source_slug
      metadata['dc:creator#adminstrative_unit'] = project['administrative_unit']
      metadata['dc:creator#affiliation'] = project['affiliation']
      metadata['nd:osfProjectIdentifier'] = osf_project_identifier
      metadata['dc:creator'] = map_creator
      metadata['dc:type'] = project['package_type']
      metadata
    end
sets metadata