Yadda za ka aiwatar sauri kashe moto?

Question

Accepted Answer

**Sauri kashe moto** yana nufin tsayar da server cikin tsafta lokacin da ya samu siginar kamatawa — kammala bubuwan da ke tafiya, rufe haɗin gida (DB, da sauransu), da fitar da albarkatun — kaɗai maimaikon kutse shi kai tsaye da sace bubuwan da ke aiki. Yana da mahimmanci don sarrafa lokacin juya babu da aminci.

## Me ya sa kashe moto mai gaggawa zai zama matsala

```text
Without graceful shutdown, when the process is killed (deploy, scale-down, crash):
  ✗ In-flight requests are dropped → users get errors
  ✗ DB transactions left incomplete
  ✗ Connections not closed cleanly → leaks/locks
```

A lokacin sarrafa lokacin juya da aikin kai tsaye, ana tsayar da aiki sau da sau — yin shi da tsafta shi ne abin da ya sa sarrafa lokacin juya ta kasance kamar do.

## Aiwatarwa

```js
import http from "http";
const server = http.createServer(app);
server.listen(3000);

async function shutdown(signal) {
  console.log(`${signal} received — shutting down gracefully`);

// 1. Stop accepting NEW connections; finish existing ones
  server.close(async () => {
    // 2. This callback runs once all active requests have completed
    await db.end();            // close database pool
    await redis.quit();        // close other connections
    console.log("clean shutdown complete");
    process.exit(0);           // exit successfully
  });

// 3. Safety net: force-exit if cleanup hangs too long
  setTimeout(() => {
    console.error("forced shutdown — cleanup timed out");
    process.exit(1);
  }, 10_000).unref();
}

// Listen for termination signals
process.on("SIGTERM", () => shutdown("SIGTERM")); // sent by orchestrators (k8s, Docker)
process.on("SIGINT", () => shutdown("SIGINT"));   // Ctrl+C in dev
```

Tsarin: kama sigina → `server.close()` (tsaya haɗin gida sabuwa, bugi da aka samu) → rufe DB/Redis/albarkatun da sauransu → fita. **Tsaf-taban tsaka-tsakin lokaci** girgije-fita in wani abu ya yi tsafe, don haɗin gida da ke tsafe ba zai iya dakatar da kashe moto har abada ba.

## Sigina

```text
SIGTERM → the standard "please terminate" signal from orchestrators on deploy/scale-down
SIGINT  → Ctrl+C (development)
SIGKILL → cannot be caught (force kill) — graceful shutdown can't help here
```

## A muhimman gidajen ajiya

```text
Kubernetes/Docker send SIGTERM, wait a grace period (e.g. 30s), THEN SIGKILL.
Your app must finish within that window → keep the shutdown timeout shorter.
Readiness probes should mark the pod unready so the load balancer stops sending traffic.
```

## Me ya sa yana da mahimmanci

Sauri kashe moto shi ne abin da ya ba da ikon **sarrafa lokacin juya babu** da aiki mai aminci a cikin yanayin zamani (musamman ajiya/tsarawa), inda aka tsayar da aiki sau-sau da sake dawo.

Ba tare da shi ba, kowane sarrafa lokacin juya ko kashe gida yai watsewar bubuwan da ke aiki da kuma da sanin samun kawo.

Aiwatar tsarin kama sigina → tsaya karba → bugi → rufe albarkatun → fita (tare da ginin tsafi na tsaka-tsakin lokaci) shine alama na jiya-suke shirya Node aiki da kuma mahimmanci amma barcin karewa amma muhimmancin aiki.