index.js

'use strict';
console.log('Loading function');

let doc = require('dynamodb-doc');
let dynamo = new doc.DynamoDB();

function date_desc(a, b) {
    let aa = new Date(a.date);
    let bb = new Date(b.date);
    if (aa < bb) return -1;
    if (aa > bb) return 1;
    return 0;
}
exports.handler = (event, context, callback) => {
    dynamo.scan({"TableName": "kinesis_sensor_datas"}, (err, data) => {
        if (err) {
            callback(err,data);
        } else {
            let watt1 = data.Items.filter((d)=>{return d.type === "watt"});
            let temp1 = data.Items.filter((d)=>{return d.type === "temperature"});
            let humi1 = data.Items.filter((d)=>{return d.type === "humidity"});
            let watt = watt1.sort(date_desc).map((d)=>{return d.value}); 
            let temp = temp1.sort(date_desc).map((d)=>{return d.value});
            let humi = humi1.sort(date_desc).map((d)=>{return d.value});
            callback(err,{device: data.Items[0].device, watt: watt, temperature: temp, humidity: humi});
        }
    });
};