TORBA: trading contracts for CORBA
Raphaël Marvie, Philippe Merle, Jean-Marc Geib, Sylvain P. Leblanc · 2001
Trading is a key function in the context of distributed applications: It allows runtime discovering of available resources. In order to standardize this function, the Open Distributed Processing (ODP) and Object Management Group (OMG) have speci ed a trading service for CORBA objects: The CosTrading. This speci cation has two main drawbacks: First, this service is complex to use from applications and second, it does not oer type checking of trading requests at compilation time. Both are discussed in this paper. The main goal of our Trader Oriented Request Broker Architecture (TORBA) is to provide a trading framework and its associated tools, which tend to oer typed trading operations that are simple to use from applications and checked at compilation time. In that, we de ne the concept of Trading Contracts, written with the TORBA De nition Language (TDL). Such contracts are then compiled to generate trading proxies oering simpleto -use interfaces. These interfaces completely hide the complexity of the ODP/OMG CosTrading APIs. In the meantime, TDL contracts could be dynamically used through a generic graphical console exploiting a contract repository. The example used in this paper, clearly states the advantages brought by the TDL trading contracts: type checking at compilation time, simple to use, and providing a powerful framework for CORBA object trading.