What is sntp?
The sntp npm package is a simple Network Time Protocol (NTP) client for Node.js. It allows you to synchronize your system time with NTP servers, ensuring accurate timekeeping for your applications.
What are sntp's main functionalities?
Time Synchronization
This feature allows you to request the current time from an NTP server. The code sample demonstrates how to use the sntp package to get the current time from 'pool.ntp.org' and log it to the console.
const Sntp = require('sntp');
// Request the current time from an NTP server
Sntp.time({ host: 'pool.ntp.org', port: 123 }, (err, time) => {
if (err) {
console.error('Failed to get time:', err);
return;
}
console.log('Current time:', new Date(time.now));
});
Custom NTP Server
This feature allows you to specify a custom NTP server to synchronize time with. The code sample shows how to get the current time from 'time.google.com' and log it to the console.
const Sntp = require('sntp');
// Request the current time from a custom NTP server
Sntp.time({ host: 'time.google.com', port: 123 }, (err, time) => {
if (err) {
console.error('Failed to get time:', err);
return;
}
console.log('Current time from custom server:', new Date(time.now));
});
Time Offset
This feature allows you to calculate the time offset between your system time and the NTP server time. The code sample demonstrates how to get the time offset from 'pool.ntp.org' and log it to the console.
const Sntp = require('sntp');
// Request the current time and calculate the offset
Sntp.time({ host: 'pool.ntp.org', port: 123 }, (err, time) => {
if (err) {
console.error('Failed to get time:', err);
return;
}
console.log('Time offset:', time.t);
});
Other packages similar to sntp
ntp-client
The ntp-client package is another NTP client for Node.js. It provides similar functionality to sntp, allowing you to synchronize your system time with NTP servers. However, ntp-client offers a simpler API and is easier to use for basic time synchronization tasks.
ntp-time
The ntp-time package is a Node.js module for retrieving the current time from NTP servers. It offers similar functionality to sntp, with a focus on providing accurate timekeeping for applications. It is a good choice if you need a reliable NTP client with minimal configuration.
sntp
An SNTP v4 client (RFC4330) for node. Simpy connects to the NTP or SNTP server requested and returns the server time
along with the roundtrip duration and clock offset. To adjust the local time to the NTP time, add the returned t
offset
to the local time.
![Build Status](https://secure.travis-ci.org/hueniverse/sntp.png)
Usage
var Sntp = require('sntp');
var options = {
host: 'nist1-sj.ustiming.org',
port: 123,
resolveReference: true,
timeout: 1000
};
Sntp.time(options, function (err, time) {
if (err) {
console.log('Failed: ' + err.message);
process.exit(1);
}
console.log('Local clock is off by: ' + time.t + ' milliseconds');
process.exit(0);
});
If an application needs to maintain continuous time synchronization, the module provides a stateful method for
querying the current offset only when the last one is too old (defaults to daily).
Sntp.offset(function (err, offset) {
console.log(offset);
Sntp.offset(function (err, offset) {
console.log(offset);
});
});
To set a background offset refresh, start the interval and use the provided now() method. If for any reason the
client fails to obtain an up-to-date offset, the current system clock is used.
var before = Sntp.now();
Sntp.start(function () {
var now = Sntp.now();
Sntp.stop();
});