RE: Chaining <xs:import> statements

The correct way is to import both schemas in your base schema, which as
you noticed, makes the warning go away. The child schema will not be
imported twice since the implementation keeps track of duplicate imports
of the same schema.

 

 

-----Original Message-----
From: xmlschema-dev-request@w3.org [mailto:xmlschema-dev-request@w3.org]
On Behalf Of Delmerico, James
Sent: Tuesday, June 22, 2004 9:12 AM
To: xmlschema-dev@w3.org
Subject: Chaining <xs:import> statements

 

I have a situation where my schema imports a schema (parent) which, in
turn, imports another schema (child).  I am referencing elements from
both schemas in my schema but only importing the (parent) schema while
declaring both namespaces in my schema.

 

What I have found is the .NET implementation of XML Schema complains
about this with the following warning:

 

"Namespace 'baseURI' is not available to be referenced in this schema."

 

The schema still properly validates the document even items coming from
the (child) schema, but the warning concerns me.  If I <import> the
(child) in my schema the warning goes away, but this also seems
incorrect - would I not be importing the schema twice (implementation
issues aside)?

 

What should be correct way to handle this situation?

 

Here is a simple contrived example that demonstrates the issue:

 

Base.xsd

<?xml version="1.0" encoding="UTF-8"?>

<xs:schema elementFormDefault="qualified"
attributeFormDefault="unqualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="baseURI"
>

            <xs:complexType name="baseType">

                        <xs:sequence    >

                                    <xs:element name="name"
type="xs:string"/>

                                    <xs:element name="age" type="xs:int"
/>

                        </xs:sequence   >          

            </xs:complexType>

</xs:schema>

 

Composite.xsd

<?xml version="1.0" encoding="UTF-8"?>

<xs:schema elementFormDefault="qualified"
attributeFormDefault="unqualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
targetNamespace="compositeURI"          

 xmlns:b="baseURI">

<xs:import schemaLocation="base.xsd" namespace="baseURI"/> 

            <xs:complexType name="composite">

                                    <xs:sequence maxOccurs="unbounded"
>

                                                <xs:element
name="person" type="b:baseType" />

                                                <xs:element
name="reference" type="b:baseType" />

                                    </xs:sequence> 

            </xs:complexType>       

</xs:schema>

 

Interview.xsd

<?xml version="1.0" encoding="UTF-8"?>

<xs:schema elementFormDefault="qualified"
attributeFormDefault="unqualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:b="baseURI"
xmlns:c="compositeURI">

            <xs:import namespace="compositeURI"
schemaLocation="composite.xsd"            />

            <!-- warning unless uncommented -->

            <!-- xs:import namespace="baseURI" schemaLocation="base.xsd"
/ -->

            <xs:element name="root" type="people"  />

            <xs:complexType name="people">

                        <xs:sequence maxOccurs="10">

                            <xs:element name="interviewer"
type="b:baseType" />

                                    <xs:element name="candidate"
type="c:composite" />

                        </xs:sequence>

            </xs:complexType>       

</xs:schema>

 

Instance.xml

<?xml version="1.0" encoding="UTF-8"?>

<!--Sample XML file generated by XMLSPY v2004 rel. 4 U
(http://www.xmlspy.com)-->

<root xmlns:b="baseURI" xmlns:c="compositeURI"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="interview.xsd">

            <interviewer>

                        <b:name>Hal</b:name>

                        <b:age>36</b:age>        

            </interviewer>

            <candidate>

                        <c:person>

                                    <b:name>Dave</b:name>           

                                    <b:age>45</b:age>        

                        </c:person>

                        <c:reference>

                                    <b:name>Frank</b:name>         

                                    <b:age>51</b:age>        

                        </c:reference>

            </candidate>

</root>

 

Thanks!

 

James Delmerico

Senior Technical Architect, IPS-Sendero

(770) 409-0047 x437

230 Scientific Dr, Suite 800

Norcross, GA  30092