Infrastructure logic Clause Samples

Infrastructure logic. The logic of the Infrastructure, i.e. the way resources should interact to support special community applications, will be modified to support the notions of: • Regions: set of resources defining the interaction boundaries of such resources. A resource is activated in the context of a region and can only interact with the resources in the same region at that moment in time. For example, an UI belongs to one region; a query execution can only be demanded to the Search Services available in the same region of the User Interface at search-time. • Groups: set of resources bound together by particular application-oriented properties. Groups do not define any interaction boundaries between the resources they contain; a group is used to support actions on sets of resources. For example, an Index Service should be designed to run a query on a group of Index DSs, rather than on an explicit list of such DSs. The overall organization of the system can be notably simplified by this simple and natural notion. • API contracts: a Service implements an API whose contract establishes its method’s signatures and semantics. WSDL and Java Stub of the Services are available from the support site. • Sub-Services: Services implementing only a part of an API contract. The existence of sub-Services must be declared as an explicit dependency in the IS. Examples are: the embedded ResultSet of the ICM Index obeys only to a sub-part of the ResultSet Service contract, that of ResultSet access. As such, is a sub-ResultSet. • Moving from Repository Services to Repository Data Structures. Indeed, Repositories are not DRIVER Services, but rather Data Structures to be managed by a special Service, called Repository Management Service. The Service operates as a generic OAI-PMH Repository harvester, returning result sets of the harvesting results. It therefore operates independently of the Aggregation Service, which will deal with input/output ResultSets, and can be reused for other purposes by other Services.