public static StreamToken GenerateXmpStream(PdfDocumentBuilder.DocumentInformationBuilder builder, decimal version,
PdfAStandard standard)
{
XNamespace xmpMeta = XmpMetaNamespace;
XNamespace rdf = RdfNamespace;
var emptyRdfAbout = new XAttribute(rdf + "about", string.Empty);
var rdfDescriptionElement = new XElement(rdf + "Description", emptyRdfAbout);
// Dublin Core Schema
AddElementsForSchema(rdfDescriptionElement, DublinCorePrefix, DublinCoreNamespace, builder,
new List <SchemaMapper>
{
new SchemaMapper("format", b => "application/pdf"),
new SchemaMapper("creator", b => b.Author),
new SchemaMapper("description", b => b.Subject),
new SchemaMapper("title", b => b.Title)
});
// XMP Basic Schema
AddElementsForSchema(rdfDescriptionElement, XmpBasicPrefix, XmpBasicNamespace, builder,
new List <SchemaMapper>
{
new SchemaMapper("CreatorTool", b => b.Creator)
});
// Adobe PDF Schema
AddElementsForSchema(rdfDescriptionElement, AdobePdfPrefix, AdobePdfNamespace, builder,
new List <SchemaMapper>
{
new SchemaMapper("PDFVersion", b => "1.7"),
new SchemaMapper("Producer", b => b.Producer)
});
var pdfAIdContainer = GetVersionAndConformanceLevelIdentificationElement(rdf, emptyRdfAbout, standard);
var document = new XDocument(
new XElement(xmpMeta + "xmpmeta", GetNamespaceAttribute(XmpMetaPrefix, XmpMetaNamespace),
new XAttribute(xmpMeta + "xmptk", Xmptk),
new XElement(rdf + "RDF",
GetNamespaceAttribute("rdf", rdf),
rdfDescriptionElement,
pdfAIdContainer
)
)
);
var xml = document.ToString(SaveOptions.None).Replace("\r\n", "\n");
xml = $"<?xpacket begin=\"\ufeff\" id=\"W5M0MpCehiHzreSzNTczkc9d\"?>\n{xml}\n<?xpacket end=\"r\"?>";
var bytes = Encoding.UTF8.GetBytes(xml);
return(new StreamToken(new DictionaryToken(new Dictionary <NameToken, IToken>
{
{ NameToken.Type, NameToken.Metadata },
{ NameToken.Subtype, NameToken.Xml },
{ NameToken.Length, new NumericToken(bytes.Length) }
}), bytes));
}
private static void AddElementsForSchema(XElement parent, string prefix, string ns, PdfDocumentBuilder.DocumentInformationBuilder builder,
List <SchemaMapper> mappers)
{
var xns = XNamespace.Get(ns);
parent.Add(GetNamespaceAttribute(prefix, xns));
foreach (var mapper in mappers)
{
var value = mapper.ValueFunc(builder);
if (value == null)
{
continue;
}
parent.Add(new XElement(xns + mapper.Name, value));
}
}
