Node-RED function node to combine SensorTag messages into single payload.

node-red-sensortag.js

// This function node combines all of the async values
// reported by the sensor tag node into a single
// payload. The flow will only continue when all values
// have been received.

var payload = context.get('payload') || { data: {} };

// Number of total attributes to report.
// When we collect all attributes from the
// sensor tag, the flow will continue.
// If you change what is read in the sensor tag config,
// this number will also have to change.
var NUM_ATTRIBUTES = 13;

switch(msg.topic) {
    case 'sensorTag/temperature':
        payload.data.temperatureObject = msg.payload.object;
        payload.data.temperatureAmbient = msg.payload.ambient;
        break;
    case 'sensorTag/humidity':
        payload.data.humidity = msg.payload.humidity;
        break;
    case 'sensorTag/pressure':
        payload.data.pressure = msg.payload.pressure;
        break;
    case 'sensorTag/accelerometer':
        payload.data.accelerometerX = msg.payload.x;
        payload.data.accelerometerY = msg.payload.y;
        payload.data.accelerometerZ = msg.payload.z;
        break;
    case 'sensorTag/gyroscope':
        payload.data.gyroscopeX = msg.payload.x;
        payload.data.gyroscopeY = msg.payload.y;
        payload.data.gyroscopeZ = msg.payload.z;
        break;
    case 'sensorTag/magnetometer':
        payload.data.magnetometerX = msg.payload.x;
        payload.data.magnetometerY = msg.payload.y;
        payload.data.magnetometerZ = msg.payload.z;
        break;
}

context.set('payload', payload);

// We've got all values. Return the new payload and
// clear the payload stored in context.
if(Object.keys(payload.data).length === NUM_ATTRIBUTES) {
    context.set('payload', null);
    msg.payload = payload;
    return msg;
}

return null;