59 lines
1.4 KiB
TypeScript
59 lines
1.4 KiB
TypeScript
|
import { MILLISECONDS_IN_SECOND } from "utils/constants";
|
||
|
|
|
||
|
|
type NTPResponse = {
|
||
|
|
backoff: number;
|
||
|
|
now: number;
|
||
|
|
optout?: boolean;
|
||
|
|
};
|
||
|
|
|
||
|
|
const DEFAULT_BACKOFF_SECONDS = 300;
|
||
|
|
const HOUR_IN_SECONDS = 3600;
|
||
|
|
const NTP_SERVER = "https://use.ntpjs.org/v1/time.json";
|
||
|
|
|
||
|
|
const NtpReqOptions = {
|
||
|
|
cache: "no-cache",
|
||
|
|
credentials: "omit",
|
||
|
|
keepalive: false,
|
||
|
|
mode: "cors",
|
||
|
|
priority: "high",
|
||
|
|
referrerPolicy: "no-referrer",
|
||
|
|
// eslint-disable-next-line unicorn/no-null
|
||
|
|
window: null,
|
||
|
|
} as RequestInit;
|
||
|
|
|
||
|
|
const getNtpResponse = async (): Promise<NTPResponse> => {
|
||
|
|
const ntpResponse = await fetch(NTP_SERVER, NtpReqOptions);
|
||
|
|
const ntpJsonResponse = (await ntpResponse.json()) as NTPResponse;
|
||
|
|
|
||
|
|
return ntpJsonResponse || {};
|
||
|
|
};
|
||
|
|
|
||
|
|
let msAheadBy: number;
|
||
|
|
|
||
|
|
const pollNtpTime = async (): Promise<void> => {
|
||
|
|
const requestStartTime = Date.now();
|
||
|
|
const {
|
||
|
|
backoff = DEFAULT_BACKOFF_SECONDS,
|
||
|
|
now = 0,
|
||
|
|
optout = false,
|
||
|
|
} = await getNtpResponse();
|
||
|
|
|
||
|
|
if (now) {
|
||
|
|
msAheadBy = requestStartTime - Math.ceil(now * MILLISECONDS_IN_SECOND);
|
||
|
|
}
|
||
|
|
|
||
|
|
setTimeout(
|
||
|
|
pollNtpTime,
|
||
|
|
(optout ? HOUR_IN_SECONDS : backoff) * MILLISECONDS_IN_SECOND
|
||
|
|
);
|
||
|
|
};
|
||
|
|
|
||
|
|
export const getNtpAdjustedTime = (): Date => {
|
||
|
|
if (typeof msAheadBy !== "number") {
|
||
|
|
msAheadBy = 0;
|
||
|
|
pollNtpTime();
|
||
|
|
}
|
||
|
|
|
||
|
|
return new Date(Date.now() - msAheadBy);
|
||
|
|
};
|