Web Services API Versioning

Question

I offer a small Web Services API to my clients which I plan to evolve over time. So I need some sort of versioning, but I can\'t find any information about how you do someth

Answer 1

The most common strategy that I've seen is to version the WSDL by adding versioning identification (typically yyyy/MM[/dd]) to the namespace of objects in the wsdl, viz:

targetNamespace="http://schemas.mycompany.com/2010/01/widgets"

This can be done either at a per-type (types/schema) level or at the whole WSDL level - in 1.1 or in 2.0.

Somewhat dated, but this link from IBM Developer Works provides the rationale for this approach, and specifically when versions need to be incremented:

Backwards version compatable / non-breaking changes:

• Adding new operations
• Adding new types

Breaking changes:

• Removing or renaming operations
• Changing parameters to a method
• Changing a complex type