Publish MQTT message with JSON payload

Setup, Configuration and Use Items & Sitemaps
2

I found an workaround through a rule:

Items:

Switch button
String locationRequest "[%s]" {mqtt=">[rabbit:owntracks/peter/phone/cmd:command:*:default]"}

Sitemaps:

Switch item=button label="Update" mappings=[ON="Now"]

Rules:

rule "mqtt publish"
when
    Item button received command
then
    locationRequest.sendCommand("{\"_type\":\"cmd\",\"action\":\"reportLocation\"}")
end

Hope it helps

Peter