Simulation, Stubs and Quality

The world of SOA and integration often involves disparate teams, sometimes in the same organisations, sometimes in different organisations. Integration projects for many years now have involved calling systems that may not exist yet or that cannot be used for testing. Green Hat, an IBM Company offer a solution through their GH VIE (Virtual Integration Environment) product, seamlessly integrated into GH Tester and able to provide production level performance simulation. Users can build simple stubs that return prefixed responses, make decisions based on inputs to return a variety of different responses, and even use datasheets to provide parameterised stub behaviours that can be extended simply by adding another row to a spreadsheet.  

Stubs can be used during performance tests too, distributed out to allow theoretical limits of systems that might otherwise be limited by components too slow to cope with high transaction volumes, allowing exploration of what-if scenarios.

Stubs also play an important role with distributed teams, allowing testing to flow around bottlenecks and to enable teams to perform pre-integration with these stubs, reducing the possibility of fundamental errors being detected in the closing stages of the project.

Green Hat stubs are not limited to XML, web services or databases. A range of out-of-the-box industry protocols offers support for HL7, IATA, SWIFT and more on top of all the middleware protocols supported. A powerful user-extendable API allows customers to quickly build stubs for other systems, enabling testing where before it was impossible.

When GH Tester starts a test, it can automatically start the necessary stubs to go with it, ensuring that unresolved system dependencies can be provided with pre-canned behaviours. The user is in control of which stub is used, allowing a wide variety of different situations to be modeled, depending on the testing scenario.