A function node for Node-RED that assembles data from WoTKit to create an HTTP request.

Node-RED Function as API controller.

// Return an error if data is empty.
if (msg.payload.length === 0){
    msg.payload = {"error":"no data found"};
    return msg;
}

// Get the values as an array
var values = []
var sensors = []
msg.payload.map(function(element){
    values.push(element.value)
    if (sensors.indexOf(element.sensor_name) == -1 && element.sensor_name !== null)
        sensors.push(element.sensor_name)
});

// Compute the average
var average = values.reduce(function(previous, current, index, array) {
  return previous + current;
}) / values.length;

// Assemble response and return
msg.payload = {'average_value': average, 'sensors_parsed':sensors, 'data_points' : values.length }
return msg;