Introduction

Eclipse Ditto™ is an open source framework for creating and managing digital twins in the IoT. Verhaeg.IoT.Ditto is a small class library that wraps the Ditto websocket and REST interface and makes this usable in other projects. You can find more information on https://www.marioverhaeg.nl/tag/ditto/

Usage

DittoManager

Start the DittoManager using:

DittoManager.Start(uri, username, password);

DittoManager.Instance().Write(obj) accepts objects of the type "NewThing", part of the Ditto-API-2.cs file. The object is taken from the queue and updated to Ditto.

Example:

NewThing t = new NewThing();
t.Definition = "Verhaeg.IoT.Energy:forecast:1.0.0";

// Create attributes
Attributes ats = new Attributes();
ats.AdditionalProperties.Add("name", "Verhaeg.IoT.Energy.Forecast:x");

DittoManager.Instance().Write(t);

(note that the "name" attribute should meet the specifications of a ThingId: https://www.eclipse.org/ditto/protocol-specification-things.html)

DittoWebSockerManager

The DittoWebSocketManager connects to the Ditto websocket and subscribes to the events based on the ns parameter. The formatting of the ns parameter is described on the Ditto website: https://www.eclipse.org/ditto/httpapi-protocol-bindings-websocket.html

The example below will subscribe to all events:

START-SEND-EVENTS

The example below will subscribe to selected events of a specific thingId:

START-SEND-EVENTS?filter=like(thingId,\"Verhaeg.IoT.Host:Chromecast\")

You inherit the DittoWebSockerManager in another class to capture its events. Example:

public class Host : DittoWebSocketManager
{
  public Host() : base("START-SEND-EVENTS?filter=like(thingId,\"Verhaeg.IoT.Host:Chromecast\")", "Ditto_Chromecast")
  {
    
  }
  public override void SendToManager(string str)
  {
    // str contains the Ditto event
  }
}