# Add-on Definitions

Every add-on has to provide meta information such as add-on type, id or name.

Background information: The meta information of all add-ons is accessible through the org.openhab.core.addon.AddonInfoRegistry service.

Although add-on definitions are usually specified in a declarative way (as described in this section), they can also be provided as org.openhab.core.addon.AddonInfo. Any AddonInfo must be registered as service at the OSGi service registry. The full Java API for addon definitions can be found in the Java package org.openhab.core.addon.

For the declarative way, you add your add-on information in form of an addon.xml file to the bundle's folder /src/main/resources/OH-INF/addon/. If the add-on consists of more than one bundle, only one addon.xml is allowed (in the main-bundle).

# XML Structure for Add-on Definitions

<?xml version="1.0" encoding="UTF-8"?>
<addon:addon id="addonID"
    xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"
    xmlns:addon="https://openhab.org/schemas/addon/v1.0.0"
    xsi:schemaLocation="https://openhab.org/schemas/addon/v1.0.0
        https://openhab.org/schemas/addon-1.0.0.xsd">

  <type>String</type>
  <name>String</name>
  <description>String</description>

  <service-id>String</service-id>

  <config-description>
    ...
  </config-description>
  OR
  <config-description-ref uri="{addon|thing-type|channel-type|any_other}:addonID:..." />

  <discovery-methods>
    ...
  </discovery-methods>

</addon:addon>
Property Description
addon.id (opens new window) An identifier for the add-on mandatory
type Either automation, binding, misc, persistence, transform, ui or voice mandatory
name A human-readable name for the add-on mandatory
description A human-readable description for the add-on optional
connection none for add-ons that have no interactions with external systems at all, local for add-ons that only interact locally without internet access, hybrid for add-ons that interact locally without internet access, but can optionally use a cloud connection for extended functionality (such as discovery), cloud for add-ons that require a cloud connection optional
countries List of two-letter ISO country codes (ISO 3166-1 alpha-2) that are supported (all countries if empty). Must be in lowercase optional
service-id The ID (service.pid or component.name (opens new window)) of the main binding service, which can be configured through OSGi configuration admin service. Should only be used in combination with a config description definition optional
config-description The configuration description for the binding within the ConfigDescriptionRegistry (cf. Configuration Description) optional
config-description-ref The reference to a configuration description for the binding within the ConfigDescriptionRegistry optional
config-description-ref.uri The URI of the configuration description for the binding within the ConfigDescriptionRegistry mandatory
discovery-methods A set of xml elements that describe how the system can scan the network to discover present devices optional

The full XML schema for add-on definitions is specified in the Add-on XSD (opens new window) file.

Hints:

  • The attribute uri in the section config-description is optional, it should not be specified in add-on definition files because it's an embedded configuration. If the uri is not specified, the configuration description is registered as type:addonID, otherwise the given uri is used.
  • If a configuration description is already specified somewhere else and the add-on wants to (re-)use it, a config-description-ref should be used instead.
  • Normally the service id must not be defined, because it is implicitly set to "type.<addonId>". An add-on can register an OSGi service which implements the ManagedService interface and define the service.pid as e.g."binding.hue" to receive the configuration.

# Discovery Methods

The system can scan the network for present devices to determine if it should suggest to install specific addons during setup. Optionally, if you want the system to scan the user's network for your addon then you need to include additional discovery-method fields.

XML Element Name Description Instances
discovery-methods Wrapper for discovery-method elements (see below). Zero or one instances per file.
discovery-method Complex XML element describing an addon discovery method. Zero or more instances per file.
service-type The type of discovery service (see table below). Mandatory one per discovery-method.
discovery-parameters Wrapper for discovery-parameter elements (see below). Zero or one instances per discovery-method.
discovery-parameter A parameter name and value used for settings of the add-on finder process. Zero or more instances per discovery-parameters.
name A settings parameter name. Mandatory one instance per discovery-parameter.
value A settings parameter value. Mandatory one instance per discovery-parameter.
match-properties Wrapper for match-property elements (see below). Zero or one instances per discovery-method.
match-property A property name and regular expression used for matching discovery findings. Zero or more instances per match-properties.
name A property name to search for. Mandatory one instance per match-property.
regex A regular expression (or plain string) that needs to match the property name. Mandatory one instance per match-property.
Service Type Description
ip Service to discover add-ons by scanning for devices via a UDP 'ping' broadcast on the LAN.
mdns Service to discover add-ons by scanning for devices using the mDNS discovery service.
processs Service to discover add-ons by checking processes running on the PC.
upnp Service to discover add-ons by scanning for devices using the UPnP discovery service.
usb Service to discover add-ons by scanning for USB devices attached to the PC.

Notes:

  • A discovery-method may contain multiple match-property entries, and in such a case all entries must match i.e. it a logical AND function is applied.
  • If you want to apply a logical OR function you can define a second separate discovery-method containing the respective match-property entry.
  • Different add-on discovery finders may need different discovery-parameters. Check the JavaDoc of the respective 'org.openhab.core.config.discovery.addon.*' finder class on GitHub. Or see the mdns example below.
  • The match-property has different allowed values for its name element depending on the discovery service-type, as shown in the table below.
Service Type Allowed match-property name values
ip "response".
mdns Frequently used properties are "name", and "application". But mDNS permits any property name depending on the service concerned.
process "command", "commandLine".
upnp "deviceType", "manufacturer", "manufacturerURI", "modelName", "modelNumber", "modelDescription", "modelURI", "serialNumber", "friendlyName".
usb "product", "manufacturer", "chipId", "remote".

# Example

The following code gives an example for an add-on definition used in bindings.

<?xml version="1.0" encoding="UTF-8"?>
<addon:addon id="bindingID"
    xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"
    xmlns:addon="https://openhab.org/schemas/addon/v1.0.0"
    xsi:schemaLocation="https://openhab.org/schemas/addon/v1.0.0
        https://openhab.org/schemas/addon-1.0.0.xsd">

  <type>binding</type>
  <name>hue Binding</name>
  <description>The hue Binding integrates the Philips hue system. It allows to control hue bulbs.</description>

  <connection>local</connection>

  <discovery-methods>
    <discovery-method>
      <serviceType>mdns</serviceType>
      <discovery-parameters>
        <discovery-parameter>
          <name>mdnsServiceType</name>
          <value>_hue._tcp.local.</value>
        </discovery-parameter>
      </discovery-parameters>
    </discovery-method>
    <discovery-method>
      <service-type>upnp</service-type>
      </match-properties>
        <match-property>
          <name>modelName</name>
          <regex>Philips hue bridge</regex>
        </match-property>
      </match-properties>
    </discovery-method>
  </discovery-methods>

</addon:addon>