AdditionalDocumentReference error

[idilalemdar]

Hello,

I have been trying to create an Invoice with UBL2.1, specifically UBLTR. Everything UBLTR asks is OK in my invoice, except when I try to send my invoice to the provider, the response body shows me this error:

<response_message>The element 'Invoice' in namespace
    'urn:oasis:names:specification:ubl:schema:xsd:Invoice-2' has invalid child element
    'AdditionalDocumentReference' in namespace
    'urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2'. List of possible
    elements expected: 'PaymentAlternativeCurrencyCode, AccountingCost, LineCountNumeric' in
    namespace 'urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2'.Shematron
    Control : Valid
    Invoice Serializer : Valid
</response_message>

I do not understand, AdditionalDocumentReference is a valid field under Invoice type and the example XML I have, which is a valid UBLTR Invoice, also has this field. I have been able to resolve all other UBL schematron errors but I am clueless on this one. Any help is deeply appreciated, thank you very much in advance.

[idilalemdar]

Same error message also exists when I completely omit the AdditionalDocumentReference field in the invoice.

[phax]

@idilalemdar sorry for the late response. Can you please share the document you want to parse. It seems like the order of elements is incorrect according to the XML Schema.

[idilalemdar]

No problem. I cannot share the whole document but I have 2 AdditionalDocumentReference's, rigth before them I have these lines:

<cbc:DocumentCurrencyCode xmlns="">TRY</cbc:DocumentCurrencyCode>
<cbc:TaxCurrencyCode xmlns="">TRY</cbc:TaxCurrencyCode>
<cbc:PricingCurrencyCode xmlns="">TRY</cbc:PricingCurrencyCode>
<cbc:PaymentCurrencyCode xmlns="">TRY</cbc:PaymentCurrencyCode>

And after the two AdditionalDocumentReference, I have fields like cac:Signature, cac:AccountingSupplierParty, cac:AccountingCustomerParty etc.

[phax]

Sorry, I can't make sense of the error message.
See e.g. https://github.com/phax/peppol-commons/blob/master/peppol-testfiles/src/main/resources/external/peppol-ubl/test-invoices/success/BII04%20XML%20example%20full%20core%20data%2001.xml for a valid UBL 2.1 document that contains an AdditionalDocumentReference. hth

[idilalemdar]

The example XML I have has xmlns="" as namespace under most of direct children of invoice, including AdditionalDocumentREference, like:

<cac:AdditionalDocumentReference xmlns="">
        <cbc:ID>1234567</cbc:ID>
        <cbc:IssueDate>yyyy-mm-dd</cbc:IssueDate>
        <cbc:DocumentType></cbc:DocumentType>
    </cac:AdditionalDocumentReference>

However the invoice I create does not include it:

<cac:AdditionalDocumentReference>
        <cbc:ID>1234567</cbc:ID>
        <cbc:IssueDate>yyyy-mm-dd</cbc:IssueDate>
        <cbc:DocumentType>DOCTYPE</cbc:DocumentType>
    </cac:AdditionalDocumentReference>

Besides, the example XML2s namespaces look like this:

<?xml version="1.0" encoding="utf-8" standalone="no"?>
<Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2"
         xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"
         xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2"
         xmlns:ccts="urn:un:unece:uncefact:documentation:2" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
         xmlns:ext="urn:oasis:names:specification:ubl:schema:xsd:CommonExtensionComponents-2"
         xmlns:qdt="urn:oasis:names:specification:ubl:schema:xsd:QualifiedDatatypes-2"
         xmlns:ubltr="urn:oasis:names:specification:ubl:schema:xsd:TurkishCustomizationExtensionComponents"
         xmlns:udt="urn:un:unece:uncefact:data:specification:UnqualifiedDataTypesSchemaModule:2"
         xmlns:xades="http://uri.etsi.org/01903/v1.3.2#" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2 UBL-Invoice-2.1.xsd">
    <ext:UBLExtensions>
        <ext:UBLExtension>
            <ext:ExtensionContent>
                <ds:Signature Id="SIGNATURE-ID">

whereas the invoice I generate:

<?xml version="1.0" encoding="UTF-8"?>
<Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2"
         xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"
         xmlns:cec="urn:oasis:names:specification:ubl:schema:xsd:CommonExtensionComponents-2"
         xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">
      <cec:UBLExtensions>
          <cec:UBLExtension>
              <cec:ExtensionContent>
                  <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#" Id="SIGNATURE-ID">

Could it be that these differences would cause any error in UBLTR? Also mentioned about this here: #56 (comment)

[phax]

The empty xmlns in your example has no impact:

<cac:AdditionalDocumentReference xmlns="">
        <cbc:ID>1234567</cbc:ID>
        <cbc:IssueDate>yyyy-mm-dd</cbc:IssueDate>
        <cbc:DocumentType></cbc:DocumentType>
    </cac:AdditionalDocumentReference>

As this example uses the cac prefix, the XML namespace URI for cac (as defined in xmlns:cac) is used.
Please read https://www.w3.org/TR/xml-names/ on more details on XML namespaces - they are commonly misunderstood.

This also applies to your second example: the namespace prefix list does not matter. You could also use the following namespace prefixes, and the example would be identical, as long as the cac namespace URI is identical to the hugo namespace URI and cbc to bla:

<hugo:AdditionalDocumentReference xmlns="">
        <bla:ID>1234567</bla:ID>
        <bla:IssueDate>yyyy-mm-dd</bla:IssueDate>
        <bla:DocumentType></bla:DocumentType>
    </hugo:AdditionalDocumentReference>

Think of namespace prefixes as "macros" that make the file shorter when you serialize it to disk. The "in-memory" representation always uses the URLs resolved from the namespace prefixes

[idilalemdar]

For those who might encounter the same problem in the future, here is the solution:

Turns out that UBLTR invoice also requires the element cbc:LineCountNumeric, where it denotes the number of invoice lines. Example invoice did not have that field, so I didn't add it at first but adding LineCountNumeric field solved my problem.