Validation is the means of determining whether or not a service transaction meets the business rules or requirements that apply to it.
In terms of validation, a service transaction falls into either of the following two categories:
- Successful – A successfully validated service transaction means the service transaction passes all business rules or requirements in that there is no business reason why it could not proceed to the next step in the service instance’s workflow
- Unsuccessful/failed – A service transaction that failed validation means there are issues relating to business rules that need to be addressed before it can be applied or progressed to the next step in the service instance’s workflow
Validation mainly applies to service transactions that are in an editable state – or service transaction tips.
Validation Errors
Validation details are stored against a service transaction via view nodes in the view tree, against the view node errors property. Since the view tree is used to render content relating to a service transaction, this allows validation errors to be included in the content, associated with the view node they relate to.
Error Levels
In this context, the term "error" is a generic term regarding any validation details. An "error" has a level associated to it indicating its severity. Even the term ‘severity’ is slightly misleading though, as this implies an issue and an "error" may not relate to an issue at all – it could simply be some additional information relating to a view node. A common example may be showing that an entered company name is valid and available when no other actual errors apply.
From a product perspective, Verne supports the following error levels along with their typical usage/meaning:
- error – failure to comply with a business rule, usually restricting a service transaction from progressing to the next step in it’s workflow
- warn – a warning, but otherwise similar to error level. This level is not really used in core Verne but does provide a mechanism for recording less severe errors which would likely be displayed differently and may or may not relate to different behaviour in terms of progressing to the next step in a service instance’s workflow
- info – allows informational details to be displayed for a view node. Usually a service transaction can still proceed as normal regarding info level errors and a service transaction containing view nodes with only info level errors is considered as validated successfully
Performing Validation
Validation can apply to a single view node within a service transaction’s view tree, the entire view tree, or a sub-branch of view nodes within it. Validation is performed using the following rule scopes:
Building the view tree results in the following rule scopes being called.
- instantiate – called on each view node after it is built
- viewtree-initialise – called once the entire view tree after the building of the entire view tree has finished
Verne performs validation against a service transaction, or specific view nodes within at various stages throughout the processing of a service instance.
