"Token StartElement in state Epilog would result in an invalid XML document" on InvoiceDescriptor.Save(stream, v21, Basic) about zugferd-csharp

[stephanstapel]

The answer seems to be quite simple:

The internal setter of trade line items prohibts creating them by the deserializer:

ZUGFeRD-csharp/ZUGFeRD/InvoiceDescriptor.cs

Line 175 in 01e3c9b

public List<TradeLineItem> TradeLineItems { get; internal set; } = new List<TradeLineItem>();

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[stephanstapel]

Hi @springy76,
it is really hard to guess what might have gone wrong based on the exception. Can you please provide your unit test (working without any dependencies) and the file that is generated?

[springy76]

Since the surrounding code goes through several layers of abstraction and transformation code I can't provide a simple sample, but I serialized the final InvoiceDescriptor to json. Note that TradeLineItems does not get deserialized, but I guess this is something you can fix easily since everything else looks good so far.

var jsonSerializerOptions = new JsonSerializerOptions { WriteIndented = true, Converters = { new JsonStringEnumConverter() { } } };
var json = JsonSerializer.Serialize(invoiceDescriptor, jsonSerializerOptions);
var rebuilt = JsonSerializer.Deserialize<InvoiceDescriptor>(json, jsonSerializerOptions);
var json2 = JsonSerializer.Serialize(rebuilt, jsonSerializerOptions);
Debug.Assert(json2 == json);

InvoiceDescriptor.zip

[stephanstapel]

I'm sorry, but generating the file from the data you provided works without any problem. Please try:

var jsonSerializerOptions = new JsonSerializerOptions { WriteIndented = true, Converters = { new JsonStringEnumConverter() { } } };
var json = File.ReadAllText("InvoiceDescriptorSerialized.json");
InvoiceDescriptor rebuilt = JsonSerializer.Deserialize<InvoiceDescriptor>(json, jsonSerializerOptions);
rebuilt.Save("output.xml", ZUGFeRDVersion.Version21, Profile.Basic);

[springy76]

As said, currently all TradeLineItems get stripped/ignored during Deserialize - and they seem to be the error source when they exist. If you add those 2 lines to your code you'll see:

var json2 = JsonSerializer.Serialize(rebuilt, jsonSerializerOptions);
Debug.Assert(json2 == json); // not equal, entire TradLineItems-Subtree/-Array is empty

[springy76]

The internal setter of trade line items prohibts creating them by the deserializer:

Klarer Fall von "Softwareproblem, kann man nichts machen" .

Irgendwie hatte ich die völlig irre Annahme, dass das auch in Bezug auf andere Bugreports - völlig losgelöst von diesem Issue - von Hilfe wäre, wenn man einen InvoiceDescriptor nicht nur serialisieren, sondern auch verlustfrei deserialisieren kann.