Files
patchmon.net/backend/src/utils/timezone.js
2025-11-07 22:04:27 +00:00

108 lines
2.9 KiB
JavaScript

/**
* Timezone utility functions for consistent timestamp handling
*
* This module provides timezone-aware timestamp functions that use
* the TZ environment variable for consistent timezone handling across
* the application. If TZ is not set, defaults to UTC.
*/
/**
* Get the configured timezone from environment variable
* Defaults to UTC if not set
* @returns {string} Timezone string (e.g., 'UTC', 'America/New_York', 'Europe/London')
*/
function get_timezone() {
return process.env.TZ || process.env.TIMEZONE || "UTC";
}
/**
* Get current date/time in the configured timezone
* Returns a Date object that represents the current time in the configured timezone
* @returns {Date} Current date/time
*/
function get_current_time() {
const tz = get_timezone();
// If UTC, use Date.now() which is always UTC
if (tz === "UTC" || tz === "Etc/UTC") {
return new Date();
}
// For other timezones, we need to create a date string with timezone info
// and parse it. This ensures the date represents the correct time in that timezone.
// For database storage, we always store UTC timestamps
// The timezone is primarily used for display purposes
return new Date();
}
/**
* Get current timestamp in milliseconds (UTC)
* This is always UTC for database storage consistency
* @returns {number} Current timestamp in milliseconds
*/
function get_current_timestamp() {
return Date.now();
}
/**
* Format a date to ISO string in the configured timezone
* @param {Date} date - Date to format (defaults to now)
* @returns {string} ISO formatted date string
*/
function format_date_iso(date = null) {
const d = date || get_current_time();
return d.toISOString();
}
/**
* Parse a date string and return a Date object
* Handles various date formats and timezone conversions
* @param {string} date_string - Date string to parse
* @param {Date} fallback - Fallback date if parsing fails (defaults to now)
* @returns {Date} Parsed date or fallback
*/
function parse_date(date_string, fallback = null) {
if (!date_string) {
return fallback || get_current_time();
}
try {
const date = new Date(date_string);
if (Number.isNaN(date.getTime())) {
return fallback || get_current_time();
}
return date;
} catch (_error) {
return fallback || get_current_time();
}
}
/**
* Convert a date to the configured timezone for display
* @param {Date} date - Date to convert
* @returns {string} Formatted date string in configured timezone
*/
function format_date_for_display(date) {
const tz = get_timezone();
const formatter = new Intl.DateTimeFormat("en-US", {
timeZone: tz,
year: "numeric",
month: "2-digit",
day: "2-digit",
hour: "2-digit",
minute: "2-digit",
second: "2-digit",
hour12: false,
});
return formatter.format(date);
}
module.exports = {
get_timezone,
get_current_time,
get_current_timestamp,
format_date_iso,
parse_date,
format_date_for_display,
};