Middle way between XSD all and XSD sequence

Question

I\'m defining a user element with XSD. For this example, a user has a name, email and one or more nationalities. I\'ve tried:

Answer 1

Or, since "USER" will be set up with multiple child elements, why not set it up as a complex type? Something like this should work.

<xs:complexType>
  <xs:sequence>
    <xs:element name="Name" type="xs:string" />
    <xs:element name="Password" type="xs:string" />
    <xs:element minOccurs="1" maxOccurs="unbounded" name="Nationality" type="xs:string" />
  </xs:sequence>
</xs:complexType>

Answer 2

I think what you're looking for would go against the intent of XML. It would seems strange to have a valid XML fragment like this:

<user>
  <nationality/>
  <name/>
  <nationality/>
  <email/>
  <nationality/>
</user>

It sounds like you're asking for something like what marc_s proposed:

<user>
  <name/>
  <email/>
  <nationality/>
  <nationality/>
  <nationality/>
<user>

which needs to get pushed into:

<user>
  <name/>
  <email/>
  <nationalities>
     <nationality/>
     <nationality/>
     <nationality/>
  </nationalities>
<user>

Answer 3

xs:choice wont work? If not, just wrap that in a sequence or vice versa.

Answer 4

For XSD 1.0 the suggestion from leppie works.

The XSD

<?xml version='1.0' encoding='UTF-8'?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name='user'>
    <xs:complexType>
      <xs:sequence>
        <xs:element name="name" type="xs:string" />
        <xs:element name="email" type="xs:string" />
        <xs:choice minOccurs='0' maxOccurs='unbounded'>
          <xs:element name="nationality" />
        </xs:choice>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

A sample XML document that validates against the schema

<user>
  <name>Name</name>
  <email>name@name.com</email>
  <nationality>Italian</nationality>
  <nationality>Japanese</nationality>
  <nationality>Alien</nationality>
</user>

And validation e.g. using xmllint

xmllint --noout --schema test.xsd test.xml
test.xml validate

Answer 5

Could you just turn your "nationality" thingie into its own complexType and then use that new complex type inside your xs:all?

<xs:complexType name="NationalityType">
  <xs:sequence>   
    <xs:element name="nationality" minOccurs="1" maxOccurs="unbounded" />
  </xs:sequence>
</xs:complexType>

<xs:all>
  <xs:element name="name" blabla />
  <xs:element name="email" blabla />
  <xs:element name="nationalities" type="NationalityType" />
</xs:all>

I don't have anything at hand to test this, so this is really just off the top of my head..... give it a try!

EDIT: tested it by now - it works, the only minor price to pay is that your XML will have to look something like this:

<....>
  <email>......</email>
  <nationalities>
    <nationality>ABC</nationality>
    <nationality>CDE</nationality>
  </nationalities>
  <name>.....</name>
</.....>

So you get an extra node that will contain the arbitrary long list of <nationality> items.

Marc

Answer 6

Just come across the a similar problem (I wanted to have any number of each element in any order) and solved it with a sequence of choices. Using the example above:

<?xml version='1.0' encoding='UTF-8'?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name='user'>
    <xs:complexType>
      <xs:sequence minOccurs="0" maxOccurs="unbounded">
        <xs:choice>
          <xs:element name="name" type="xs:string" />
          <xs:element name="email" type="xs:string" />
          <xs:element name="nationality" />
        </xs:choice>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

This allows you to have any number of name, email and nationality in any order.