Task Filters

Each operation in a DCS service is implemented as a task. You can provide multiple implementations of a task for a service instance, and then use task filters to direct client applications to a specific task implementation. This mechanism lets an administrator direct requests from client applications to the most appropriate implementation of an operation for that client. Task filters can also be used to construct a simple load-balancing mechanism that distributes client requests across multiple tasks based on information that the client application provides.

The task filters indicate the elements in the context object passed from the client application that must be matched to start that implementation of the task. If a task does not define any filters, then all requests for the corresponding operation might be directed to the same task implementation.

You can use task filters to implement a versioning mechanism. Client applications that expect a specific version of a task can provide information in the context object to identify the version to use.

An administrator uses the DCS Management Services console to define a task filter.