Meaning of 'Schemas validation error'

[paulhiggs]

I am trying to use xmllint to validate an XML document against a set of schemas and get the following error:

{
  errors: [
    "file_0.xml:26: element ServiceList: Schemas validity error : Element '{urn:dvb:metadata:servicediscovery:2019}ServiceList': No matching global declaration available for the validation root."
  ]
}

Line 26 of the XML document is

<ServiceList xmlns="urn:dvb:metadata:servicediscovery:2019" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tva="urn:tva:metadata:2019" version="191126165755" xsi:schemaLocation="urn:dvb:metadata:servicediscovery:2019 dvbi_v1.0.xsd">

and the node/express code being used is

console.log(xmllint.validateXML({
    xml: fs.readFileSync(path.join('sample','ASTRA_19_2_E.xml')).toString(),
    schema: [fs.readFileSync(path.join('schema','dvbi_v1.0.xsd')).toString(), 
             fs.readFileSync(path.join('schema','tva_metadata_3-1.xsd')).toString(), 
             fs.readFileSync(path.join('schema','tva_mpeg7.xsd')).toString(),
             fs.readFileSync(path.join('schema','xml.xsd')).toString()]
}));

the "sample" files can be found in https://github.com/paulhiggs/dvb-sl-check/tree/master/sample the "schema" files can be found in https://github.com/paulhiggs/dvb-sl-check/tree/master/schema

The XML document validates OK with XMLspy 2019

[paulhiggs]

Here is the most simple example to reproduce the error

let recipe_xsd=`<?xml version="1.0" encoding="utf-8"?>
<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:r="http://www.namespace.org/recipe" xmlns:s="http://www.namespace.org/servings" targetNamespace="http://www.namespace.org/recipe" version="1.0" elementFormDefault="unqualified" attributeFormDefault="unqualified">
    <import namespace="http://www.namespace.org/servings" schemaLocation="serving.xsd"/>
    <element name="recipe" type="r:recipe"/>
    <complexType name="recipe">
        <sequence>
            <element name="servings" type="s:servingsType"/>
        </sequence>
    </complexType>
</schema>`;

let serving_xsd=`<?xml version="1.0" encoding="utf-8"?>
<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:rx="http://www.namespace.org/servings" targetNamespace="http://www.namespace.org/servings" elementFormDefault="unqualified" attributeFormDefault="unqualified" version="1.0">
    <element name="guests" type="rx:servingsType"/>
    <simpleType name="servingsType">
        <restriction base="unsignedInt">
            <minInclusive value="1"/>
            <maxInclusive value="16"/>
        </restriction>
    </simpleType>
</schema>`;

let recipe_xml=`<?xml version="1.0"?>
<r:recipe xmlns:r="http://www.namespace.org/recipe" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.namespace.org/recipe recipe.xsd">
  <servings>12</servings>
</r:recipe>`;

The XML document uses a recipe schema (recive_1) which in turn uses a datatype defined in a second schema (recipe_2).

with

let e3 = xmllint.validateXML({xml:recipe_xml, schema: [recipe_xsd, serving_xsd ]});
console.dir(e3);

we get the output

{
  errors: [
    "file_0.xml:2: element recipe2: Schemas validity error : Element '{http://www.namespace.org/recipe}recipe2': No matching global declaration available for the validation root."
  ]
}

swapping the order of elements in the list of shemas to schema: [recipe2_xsd, recipe1_xsd ] gives

{
  errors: [
    "file_1.xsd:7: element element: Schemas parser error : Element '{http://www.w3.org/2001/XMLSchema}element', attribute 'type': References from this schema to components in the namespace 'http://www.namespace.org/servings' are not allowed, since not indicated by an import statement."
  ]
}