openhab-docs/_addons_transformations/jinja

id	label	title	type	description	logo	install
jinja	Jinja	Jinja - Transformation Services	transform	Transforms a value using a Jinja template.	images/addons/jinja.svg	auto

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Jinja Transformation Service

Transforms a value using a Jinja template.

The main purpose of this transformer is use in Home Assistant discovery. Therefore, not all features of the Home Assistant templating engine are supported. See also: Processing incoming data.

Available variables

Variable	Description
value	The incoming value.
value_json	The incoming value parsed as JSON.

Examples

Basic Examples

Incoming data

Given the value

{"Time":"2019-01-05T22:45:12","AM2301":{"Temperature":4.7,"Humidity":93.7},"TempUnit":"C"}

the template

{{ value_json['AM2301'].Temperature }}

extracts the string 4.7.

Outgoing data

The JINJA transformation can be used to publish simple JSON strings through, for example, the HTTP binding’s commandTransformation parameter.

Say we have a String Item which holds the following value:

This is my string

Adding the following into the commandTransformation parameter of your HTTP Thing channel

JINJA:{"msgtype":"m.text", "body":"{{value}}"}

will send the following string out of openHAB:

{"msgtype":"m.text", "body":"This is my string"}

{{value}} will be replaced by whatever the value of your Item is.

Note that if using .things files you must escape quotation marks, for example:

commandTransformation = "JINJA:{\"msgtype\":\"m.text\", \"body\":\"{{value}}\"}"

Further Reading

• Wikipedia on Jinja.
• Home Assistant discovery.
• Home Assistant templating.