AWS Lambda 时区

Question

I've been searching for a while and can't find a definitive answer on that or any oficial documentation from AWS.

I have a Lambda function on which I need to get the current date according to my timezone, but I'm unsure on which premisses I may rely to do that, and as this is a critical app, I can't simply rely on a single test or empirical result.

I would expect that lambda functions follow the timezone of the AWS region that they are hosted in OR a unique timezone for any GMT 0, but couldn't confirm it anywhere.

Could anyone please clarify how this works and if possible also point to any official documentation about that? Also, any special concerns related to daylight saving time?

My Lambda function is written on NodeJS and what I've been doing locally (on my machine) to retrieve the current date time is using new Date() .

Answer 1

Lambda time using the date object will return a date in UTC unix time (as described here ).

To get a time in a specific timezone you can use moment-timezone .

Using Javascript Date().now():

var moment = require("moment-timezone");
moment(Date().now()).tz("America/Los_Angeles").format("DD-MM-YYYY");

or using new Date():

var moment = require("moment-timezone");
var date = new Date();
moment(date.getTime()).tz("America/Los_Angeles").format("DD-MM-YYYY");

You can change the format to whatever you require, see more formats here

Regarding daylight savings time, it is possible to detect it using isDST() method as shown here

Answer 2

To avoid using an external library, you can use toLocaleString() which relies on Intl.DateTimeFormat() . You can pass it a locale and an option object that supports a " timezone " and other formating parameters.

 var today = new Date(); //UTC in lambda var localeDate = today.toLocaleString('fr-FR', { timeZone: 'Europe/Paris'}); // to get the full date string var localeHour = today.toLocaleString('fr-FR', { timeZone: 'Europe/Paris',hour: 'numeric' }); //to get just the hour console.log(localeDate); console.log(localeHour);

Answer 3

If @bbas answer didn't work for you in nodejs14.x, try this out as mentioned in :

 let date = new Date(); // UTC in lambda. let dateString = new Intl.DateTimeFormat('en-US', { timeZone: 'Asia/Kolkata', year: 'numeric', month: '2-digit', day: '2-digit'}).format(date); console.log(dateString); // prints out date in mm/dd/yyyy in 'Asia/Kolkata' timezone