feat: uptime monitor

src/app.js

@@ -52,11 +52,13 @@ const mongo = mongoose.createConnection(String(process.env.MONGO_URL), {
 
 // Fork processes
 const hackernewsFork = fork(pathTo(import.meta.url, "./hackernews.js"), { detached: true });
+const uptimeFork = fork(pathTo(import.meta.url, "./uptime.js", { detached: true }));
 
 async function terminate(caller) {
  const t = Date.now();
  bot.stop(caller);
  hackernewsFork.kill();
+ uptimeFork.kill();
  await mongo.close();
  await Sentry.flush();
  terminal.info(`${caller}: ${Date.now() - t}ms`);

src/uptime.js

@@ -0,0 +1,51 @@
+import dotenv from "dotenv";
+import got from "got";
+import * as Sentry from "@sentry/node";
+import { pathTo } from "#utils/path.js";
+
+dotenv.config({ path: pathTo(import.meta.url, "../.env") });
+
+const UPTIME_MONITOR_URL = process.env.UPTIME_MONITOR_URL;
+
+function sleep(ms) {
+ return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
+async function run(url) {
+ const searchParams = new URLSearchParams();
+ searchParams.set("msg", "OK");
+ searchParams.set("ping", "0");
+ searchParams.set("status", "up");
+
+ await got.post(url + "?" + searchParams.toString());
+}
+
+for (;;) {
+ // Don't start the uptime service if the monitor url is empty.
+ if (!UPTIME_MONITOR_URL) {
+ break;
+ }
+
+ let done = false;
+
+ // eslint-disable-next-line no-await-in-loop
+ await run(UPTIME_MONITOR_URL)
+ .catch((error) => {
+ Sentry.captureException(error);
+ })
+ .finally(() => {
+ done = true;
+ });
+
+ while (!done) {
+ // wait
+ await sleep(1000);
+ }
+
+ // How long do we need to sleep
+ const now = new Date();
+ const nextTime = new Date(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate(), now.getUTCHours(), now.getUTCMinutes() + 1, now.getUTCSeconds(), 0);
+
+ // eslint-disable-next-line no-await-in-loop
+ await sleep(nextTime.getTime() - now.getTime());
+}