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A Genom component is a server that provides a number of services and communicates through data ports with other components in the system. Services are asynchronous (meaning that they can be started without waiting for termination).

The execution of a service is controlled by a finite state automaton and an optional clock. Several services can be active in parallel in the same component, using distinct execution tasks or not.

A running service can be observed and controlled from outside the component. In particular it can be interrupted if needed, and the programmer can provide code to handle the interruption in a clean and safe way (for example offering a clean stop of an ongoing motor motion).

The algorithms executed by a service must be decomposed in chunks whose execution cannot be interrupted, and thus should not run for too long (otherwise compromising the ability to interrupt it). Those chunks form the basic code elements manipulated by Genom and are called "codels".

Genom provides a powerful exception mechanism to handle errors that can be detected during codel execution. Genom exceptions can transmit any kind of data available to the codels to describe the error to the component that called the service, making it possible to perform a diagnostic of the error, and eventually to recover from it.

So in order to build a Genom component, the programmer has to write two kind of inputs:

  • the formal description of the component, describing the services, input and output ports and other kind of information that is needed to run the component.

  • the codels themselves that implements the algorithms of the services.

Genom processes those inputs with a middleware specific template to generate several outputs:

  • the source code of the component itself, interfaced with the codels and the communication layer for the selected middleware bound to all external libraries that the component may depend upon.

  • a set of client libraries that use the chosen middleware to interact with the component. The API of those libraries are themselves middleware independent, making it possible to control component with middleware independent code.

Note that Genom templates can potentially generate any kind of source code, such as a graphical test program or even documentation, so Genom itself is highly extensible.