Apa iku process object lan apa bisa ditindakake?

Question

Accepted Answer

**`process`** yaiku global object sing menehi informasi lan kontrol marang **current Node.js process**. Iku interface mu menyang environment, command-line arguments, I/O streams, lifecycle, lan signals.

## Maca environment variables

```js
process.env.NODE_ENV;        // "production" | "development"
process.env.DATABASE_URL;    // configuration & secrets injected by the environment
const port = process.env.PORT || 3000;
```

`process.env` yaiku cara standar kanggo maca configuration lan secrets (diatur ing luar code) — pusat saka twelve-factor config.

## Command-line arguments

```js
// node script.js --name=Ann
process.argv; // ["node", "/path/script.js", "--name=Ann"]
const args = process.argv.slice(2); // skip the first two
```

## Standard I/O streams

```js
process.stdout.write("output
");   // console.log writes here
process.stderr.write("error
");    // console.error writes here
process.stdin.on("data", (chunk) => { /* read input */ });
```

## Process lifecycle & exit

```js
process.exit(0);   // exit with success code (1 = error)
process.exitCode = 1; // preferred: set code, let the process finish naturally
process.pid;       // the process id
process.cwd();     // current working directory
process.uptime();  // seconds the process has run
```

## Handling signals & uncaught errors (for graceful shutdown / safety nets)

```js
process.on("SIGTERM", () => { /* clean up, then exit — e.g. on container stop */ });
process.on("SIGINT", () => { /* Ctrl+C */ });
process.on("uncaughtException", (err) => { log(err); process.exit(1); });
process.on("unhandledRejection", (reason) => { log(reason); });
```

Listening for `SIGTERM`/`SIGINT` yaiku carane implementasi **graceful shutdown** (finish in-flight requests, close DB connections sadurunge keluar), lan uncaught-error handlers yaiku last-resort safety nets.

## Liyane useful members

```js
process.memoryUsage(); // heap stats (leak detection)
process.nextTick(cb);  // schedule a callback before the next event-loop phase
process.platform;      // "linux" | "darwin" | "win32"
```

## Kepunahen karenan penting

`process` yaiku sambungan program mu menyang runtime environment-ne.

Kowe nggunakake iku terus-terusan: maca config/secrets liwat `process.env`, nangani CLI args, lan — penting banget kanggo production — nanggep signals kanggo graceful shutdown lan last-resort error handlers.

Mangerteni iku penting banget kanggo nggawe Node applications sing bisa dikonfigurasi, kuwat, lan siap kanggo production.