Cloud Service Validation

This page grants access to a web service for validating a cloud software service specification. This validation tool was developed for the EU FP7 Broker@Cloud project, to support the continuous quality assurance objective.

Validation is a semi-formal human inspection process in which aspects of the specification are reflected back to the designer, to help determine whether the right design has been developed. This is done by checking the completeness of the state machine for the cloud service and reporting back to the designer, who may then decide whether further states or transitions are desired in the design. There is no right or wrong answer; but the designer should be able to determine when the state machine for the service should handle, or ignore particular events.

State Machine Completeness Checker

This web service checks the completeness of a service's state machine (it checks statically whether each event is explicitly handled by a specified transition in every state). It returns machine-readable data in XML format. Please supply the public URL of the XML file containing the service specification in XML format. (You may copy an example URL from the specification page).

If the input file can be read, the output will be an XML file containing the analysed state machine specification (otherwise an error message will be displayed). The root Machine node will contain a Notice node, which may contain further Analysis or Warning nodes. A Warning is issued if any states cannot be reached in the machine, or if known events are not handled by the machine. These are faults in the specification that should be rectified. An Analysis is issued if any state ignores certain events. This is not necessarily a fault, and is provided for your information.

A Notice is then also attached to each State node, giving an Analysis of which events are ignored by that state. A state may legitimately choose to ignore certain events; but the analysis allows you to check that events are handled as you really intend. The Warning is repeated for each unreachable state, as a reminder.