DataController.groovy

    @RequestMapping(value = "/data.json", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
    @ResponseBody
    JSONObject home() {
        def data = ["hum_temp": "Temperatura (\u00b0C)", "hum_hum": "Wilgotno\u015b\u0107 (%)", "bar_pres_rel": "Ci\u015bnienie (hPa)", "lux": "Jasno\u015b\u0107 (lx)", "vbat": "Nap. baterii (V)", "vreg": "Nap. sensor\u00f3w (V)"]
        def sensors = [:]
        def readings = [:]

        ['Balkon', 'Salon', 'Biuro', 'Łazienka', 'Sypialnia', 'Piwnica'].eachWithIndex { String room, int idx ->
            sensors << [(idx): ["label": room, "data": ["hum_temp", "hum_hum", "lux", "vbat", "vreg"]]]
            readings << [(idx): ["id"          : randomId, "stamp": timeStamp, "sensor_id": idx, "seq": randomId, "status": 0,
                                 "flags"       : randomId, "bar_temp": randomTemp, "bar_pres_abs": randomBarPress,
                                 "bar_pres_rel": randomBarPress, "lux": randomLux, "hum_temp": randomTemp,
                                 "hum_hum"     : randomHumHum, "vbat": randomVBat, "vreg": randomVReg]]
        }

        ["sensors": sensors, "readings": readings, "data": data]
    }