WSDL 2.0 Test Assertions
Arthur Ryman, IBM
2004-06-04
Introduction
The W3C Web Service Description Working Group will develop test
assertions for assuring the quality of the WSDL 2.0 specification. A
test assertion is a statement about valid WSDL 2.0 documents, and
related artifacts, that holds true. Test assertions are implicit in the
WSDL 2.0 specification, however, it is useful to collect them into a
Test Assertion Document (TAD) where they are given stable, unique names
and are stated very precisely. The exercise of extracting test
assertions from the specification is useful since it helps find and
correct ambiguities, inconsistencies, omissions, and other problems in
the specification. Test assertions are also important for improving the
coverage of our test suite. Our goal is to have, for each test
assertion, at least one test case that violates it.
Test Assertion Categories
There will be one TAD for each of the following major categories of
assesrtions.
- description-tad: assertions that hold when a WSDL document, and
any imported or include WSDL and XSD documents, are valid
- message-tad: assertions that hold when a message is correctly
described by a valid WSDL binding
- exchange-tad: assertions that hold when an exchange of one or
more correct messages is correclty described by a valid WSDL operation
- processor-tad: assertions that hold when a processor behaves
correctly with respect to a valid WSDL document
Z Notation
In order to achieve the required degree of precision, each test
assertion will be formally specified using Z notation. Each test assertion
will be specified as a named Z schema. The name of the Z schema will be
used to tag the source of the assertion in the normative WSDL
specification and there will be corresponding hyperlinks from each TAD
to the WSDL specification.