compass-bot/utils/misc.mjs
2023-11-02 08:29:19 +08:00

60 lines
1.5 KiB
JavaScript

import fs from 'node:fs/promises';
// Reads JSON data from file, returns null if file not found or has other errors.
export async function readJsonFile(path) {
try {
const data = await fs.readFile(path, 'utf8');
return JSON.parse(data);
} catch (error) {
return null;
}
}
// Write JSON data into a file.
export function writeJsonFile(path, data) {
const json_string = JSON.stringify(data);
return fs.writeFile(path, json_string, 'utf8');
}
// Parse format "profile@host:port", port can be undefined.
export function parseLogin(url) {
const [profile_host, port] = url.split(':');
const [profile, host] = profile_host.split('@');
return [profile, host, port ? parseInt(port) : undefined];
}
// Returns a promise, wait unitl the EventEmitter emits certian event next time.
export function waitEvent(em, event) {
return new Promise((resolve, _reject) => {
em.once(event, resolve);
});
}
export function asyncSleep(t) {
return new Promise((resolve, _reject) => {
setTimeout(resolve, t);
});
}
export function asyncTimeout(t) {
return new Promise((_resolve, reject) => {
setTimeout(reject, t);
});
}
export function promiseTimeout(p, t) {
return Promise.race([p, asyncTimeout(t)]);
}
export function yieldTask() {
return new Promise((resolve, _reject) => {
queueMicrotask(resolve);
});
}
// Checks wheather an object is iterable.
export function isIterable(obj) {
if (obj == null) { return false; }
return typeof obj[Symbol.iterator] == 'function';
}