Say hello to Orleans

In this section, we will build our first application using Orleans. Before we build the application, let's first understand more about grains and silos.

Cloud-native objects – grains

Grains are the main building blocks of applications built with Orleans. They are fundamental units of isolation, distribution, and persistence. They represent application entities. Grains are analogous to classes in the object-oriented programming model. Like classes encapsulate the data and the behavior of an entity, grains encapsulate the state and behavior of an application entity, as shown in Figure 4.1. Once a grain is activated, it will have a physical existence and an activated grain is called an activation. Activations are like objects in the object-oriented programming model. Activations can represent the digital twin of a real-world entity.

Figure 4.1 – Orleans grain

The preceding figure represents the hotel grain that we...