Restrict XSD such that it does not allow attribute on root element

Question

I need to validate XML using the following XSD

<xs:element name="root" type="rootType"/>
<xs:element name="names" type="nameType"/>
    <xs:complexType name="rootType" mixed="true">
        <xs:sequence>
            <xs:choice minOccurs="0" maxOccurs="unbounded">                
                <xs:element name="names" minOccurs="0" maxOccurs="unbounded" type="nameType"/>
                <xs:element name="root" minOccurs="0" maxOccurs="unbounded" type="rootType"/>                
            </xs:choice>
        </xs:sequence>
        <xs:attribute name="name" type="xs:string"/>
    </xs:complexType>

    <xs:complexType name="nameType" mixed="true">
        <xs:sequence>
            <xs:choice minOccurs="0" maxOccurs="unbounded">                
                <xs:element name="names" minOccurs="0" maxOccurs="unbounded" type="nameType"/>
                <xs:element name="root" minOccurs="0" maxOccurs="unbounded" type="rootType"/> 
            </xs:choice>
        </xs:sequence>
        <xs:attribute name="name" type="xs:string"/>
    </xs:complexType>

such that, the XSD should not allow the root element in the XML to have a "name" attribute.

Eg: The XSD should consider the following XML as valid

<root>
<names name="abc"></names>
<root name="xyz"></root>
</root>

and the following as invalid, since the root element of the xml has a name attribute.

<root name="rootElement">
<names name="abc"></names>
<root name="xyz"></root>
</root>

However, if the same element appears as a child element, then it can have a name attribute. Please let us know if this is feasible using XSD, if so how can we do it?

Answer 1

Define rootType without a name attribute:

<xs:complexType name="rootTypeWithoutName" mixed="true">
        <xs:sequence>
            <xs:choice minOccurs="0" maxOccurs="unbounded">                
                <xs:element name="names" minOccurs="0" maxOccurs="unbounded" type="nameType"/>
                <xs:element name="root" minOccurs="0" maxOccurs="unbounded" type="rootTypeWithName"/>                
            </xs:choice>
        </xs:sequence>
    </xs:complexType>

then define an extended type that allows the name:

<xs:complexType name="rootTypeWithName" mixed="true">
  <xs:extension base="rootTypeWithoutName">
   <xs:attribute name="name" type="xs:string"/>
  </xs:extension>
</xs:complexType>

In the global element declaration for root, use type="rootTypeWithoutName" . In the local element declaration for a nested root element (as shown above), use the type rootTypeWithName .

I haven't tested this, so there may be syntax slips, but the principle should be sound.