My Meteo Alert

// index.js
// author : adrien chan
//

'use strict';

// load modules : aws and dynamodb
var AWS = require("aws-sdk");
var dynamodb = new AWS.DynamoDB({apiVersion: '2012-08-10'});

console.log('Loading function');

exports.handler = (event, context, callback) => {

 // init current sign from event params or event config
    var currentSign;
    if (event.params !== undefined && event.params.querystring !== undefined) {
       currentSign = event.params.querystring.astrosign;
    }
    else
    if (event.astrosign !== undefined && event.astroSign !== '') {
        //console.log('astrosign noparam:'+event.astrosign);
        currentSign = event.astrosign;
    }

// guid dynamic    
function generateQuickGuid() {
    return Math.random().toString(36).substring(2, 15) +
        Math.random().toString(36).substring(2, 15);
}    

// onScan processes all records of table and generates horoscopes in json format
  function onScan(err, data) {
    if (err) {
        context.done(null, flash);
    } else {
        var horoscopes = [];
        data.Items.forEach(function(horoscope) {
            horoscopes.push({ uid: generateQuickGuid(), updateDate: now, titleText: horoscope.ThemeId.S +" Astro Meteo", mainText: horoscope.Content.S});
        });
        context.done(null, horoscopes);
    }
  }

  // init some variables
    var now = new Date().toISOString();
      var title = "my daily astro meteo ";
      var content ='astrology info extraction processing. Please retry after 10 mn.';
      var flash = { uid: generateQuickGuid(), updateDate: now, titleText: title, mainText:content};

// if no currentsign defined then call onScan for all records of table	  
if (currentSign === undefined || currentSign === '') {
  dynamodb.scan({ TableName: 'FlashBriefing' }, onScan);
}
else {
// get single record for currentSign
var params = { 
    TableName: "FlashBriefing",
    Key: {
        "ThemeId": {
          "S": currentSign
      },
    }
};

// then generates json data for currentSign
dynamodb.getItem(params, function(err, data) {
    if (err) {
        console.log(JSON.stringify(err, null, 2));
        context.done(null,flash);
    }
    else {
        console.log(JSON.stringify(data, null, 2));
        flash = { uid: generateQuickGuid(), updateDate: now, titleText: data.Item.ThemeId.S +" Astro Meteo", mainText:data.Item.ThemeId.S + " : "+data.Item.Content.S};
        context.done(null,flash);
    }
});    
}

};