Components

• Creating a component
• The elements of a Vertigo component

• Java
• Python
• Javascript

Networks are made up of any number of components which are simply Vert.x verticles or modules that are connected together according to the network configuration. Each component is a “black box” that receives input on named input ports and sends output to named output ports. By their nature, components do not know from where they received messages or to where they’re sending messages.

Creating a component

To create a Java component, extend the base ComponentVerticle class.

public class MyComponent extends ComponentVerticle {
  @Override
  public void start() {
  
  }
}

The ComponentVerticle base class is simply a special extension of the Vert.x Verticle that synchronizes with other components in the network at startup and provides Vertigo specific APIs. Once the component has completed startup it will call the start() method just like any other verticle.

The elements of a Vertigo component

The ComponentVerticle base class provides the following additional protected fields:

• vertigo - a Vertigo instance
• cluster - the Vertigo Cluster to which the component belongs
• input - the component’s InputCollector, an interface to input ports
• output- the component’s OutputCollector, an interface to output ports
• logger - the component’s PortLogger, a special logger that logs messages to output ports

The most important of these variables is the input and output objects on which messages are received and sent respectively. In Vertigo, messages flow in only one direction, so messages can only be received on input ports and sent to output ports.