Taking Care – Error Handling - Applied SOA Patterns on the Oracle Platform - page 480

There must be a strict rule indicating that all draft service versions must be delivered into
a JIT environment with a complete set for all possible "rainy day" scenarios. This ap-
proach is common for all types of EH resolutions; either you maintain them on a standard
Error Hospital using OFM policies or you delegate them to more complex EH composi-
tion controllers, linked to the Service Repository with the required EPs. In this case, ful-
filling the requirements of service composition error classifications should be the first
step, and we will look at it now.
Maintaining Exception Discoverability
Although service error definition and classification is utterly important for the reasons we
just saw, we only have enough room to provide directions for building and maintaining
such a list in the Service Repository. This exercise is part of building a Service Profile and
a Service-level profile structure (see Chapter 15 , SOA Principles of Service Design , Tho-
mas Erl, Prentice Hall ). The basis for the exercise is as follows:
• The number of frameworks that will participate in service deployment and inter-
actions.
We mentioned six, but commonly, we should focus on three: EBF, EBS, and
ABCS (see the next figure, where the color red indicates errors and orange indic-
ates Audit). For the presence of the ESR framework, we should consider Invent-
ory Endpoint as an abstraction point within EBS.
• Technical layering (vertical) and positioning of the service in core technical lay-
ers.
Naturally, we have EBF as only a single layer. Bus and Adapters (not always
physically, as some components/patterns are common, such as Adapter Factory)
can logically be Northbound and Southbound, so the service operations will also
be location-specific.
• The nature of underlying service technical resources.
The resource acquisition error from entity services sharing the same DB should
be treated with elevated priority compared to a service with a dedicated configur-
ation file, such as FSO. Continuing on that, it seems to be that Functional type
warning from task-orchestration services about gradual performance degradation
must be correlated with dehydration DB runtime metrics, and so on.
• Structure of the SOAP fault and other acknowledge and error messages.