SiteWhere Persistence

Overview

The SiteWhere persistence provider allows openHAB data to be forwarded to a SiteWhere server instance running locally or in the cloud. Selected events from an openHAB instance can be stored in SiteWhere under a virtual device with hardware id specified in the persistence provider implementation. Events are delivered via the SiteWhere agent which uses the MQTT protocol. The SiteWhere administrative application may be used to view data for the virtual device. It can also be used to issue commands to items in openHAB based on the SiteWhere command framework. See this tutorial for a step-by-step walkthrough.

Configuring SiteWhere

Both SiteWhere and openHAB by default run on port 8080, so the port will need to be changed if both are running on the same machine. To change the port for SiteWhere, open the conf/server.xml file and look for the following:

<Connector port="8080" protocol="HTTP/1.1"
    connectionTimeout="20000"
    redirectPort="8443" />

Change the port to another value such as 9090.

No configuration is necessary for SiteWhere to listen for events on the MQTT transport if using the default tenant configuration. The SiteWhere agent used by the persistence plugin is configured to send MQTT messages on the topic where SiteWhere is listening.

Configuring openHAB

The default values configured in the openHAB SiteWhere persistence plugin will work with no changes if using the default SiteWhere tenant configuration. The default values are shown below:

############################ SiteWhere Persistence Service #############################
#
# Unique hardware id of device that will receive events.
# sitewhere:defaultHardwareId=123-OPENHAB-777908324
#
# Device specification token used if device is not already registered.
# sitewhere:specificationToken=5a95f3f2-96f0-47f9-b98d-f5c081d01948
#
# MQTT broker hostname SiteWhere is listening to. 
# sitewhere:mqttHost=localhost
#
# MQTT broker port SiteWhere is listening to. 
# sitewhere:mqttPort=1883

The following configuration values may be specified to change the default behavior:

• defaultHardwareId - provides an association between the openHAB instance and a SiteWhere device. Once connected, if no device exists in SiteWhere with the given hardware id, a new openHAB virtual device will be registered under that id. All data sent from the openHAB instance will be recorded under the virtual device. If more than one openHAB instance is connecting to SiteWhere, different hardware ids should be used for each instance. SiteWhere can scale to support thousands or even millions of openHAB instances running concurrently.
• specificationToken - indicates the device specification to be used if a new device needs to be registered with SiteWhere (if the hardware id does not exist). The default value corresponds to the openHAB Virtual Device specification included with the SiteWhere sample data. This specification includes the device commands used to trigger events on the openHAB bus from SiteWhere.
• mqttHost - the host name for the MQTT broker SiteWhere is listening to.
• mqttPort - the port number for the MQTT broker SiteWhere is listening to.