Menene Buffers a cikin Node.js?

Question

Accepted Answer

**Buffer** shi ne hanyar Node na watsawa da **ainihin bayanan binar** — jerin kusan bure da aka ajiye a wajen heap V8. Domin zanen JavaScript ne don rubutu (Unicode), Buffers akwai don aiki da binar: abun fayil, fakitin hanyar sadarwa, hotuna, boye-boye, da kuma.

## Me yasa Buffers akwai

```text
JavaScript strings → text (UTF-16). Can't cleanly represent arbitrary bytes.
Buffers → raw bytes (0–255 each). For binary data that isn't text.
```

Lokacin da ka karanta fayil ko ka karba bayanan hanyar sadarwa, suna zo azaman bytes — Buffer — wanda za ka iya cire zuwa string idan shi ne rubutu, ko kuma aiki da shi azaman binar idan ba shi ba.

## Ƙirewa da amfani da Buffers

```js
const buf = Buffer.from("Hello");          // from a string → bytes
const buf2 = Buffer.from([72, 105]);       // from byte values → "Hi"
const buf3 = Buffer.alloc(10);             // 10 zero-filled bytes

buf.length;          // 5 (bytes, not characters)
buf.toString("utf8"); // "Hello" — decode back to text
buf.toString("hex");  // "48656c6c6f"
buf.toString("base64"); // "SGVsbG8="
buf[0];              // 72 — access individual bytes
```

## Inda Buffers ke bayyana

```js
// file reads without an encoding return a Buffer
const data = await fs.promises.readFile("image.png"); // Buffer (binary)
const text = await fs.promises.readFile("file.txt", "utf8"); // string (decoded)

// streams emit Buffer chunks
req.on("data", (chunk) => { /* chunk is a Buffer */ });

// crypto, compression, network protocols all work with Buffers
crypto.randomBytes(16); // a Buffer of 16 random bytes
```

Idan ka karanta fayil *ba* a saba ishara da encoding, ka ji Buffer; saba `"utf8"` kuma Node ya cirewa zuwa string don ka.

## Wani maimaitawa: bytes vs haruffa

```js
Buffer.from("café").length; // 5 (é is 2 bytes in UTF-8) — NOT 4 characters
```

Tsarin Buffer yana cikin **bytes**, wanda zai iya bambanta daga adadin haruffa don rubutun bari-byte (non-ASCII) — aiki yayin yanke bayanan binar.

## Me yasa ya mahalaci

Buffers shi ne hanyar da Node ta shiga gaida duka **bayanan binar**, wanda ba zai iya kada tafi ba a aiki na saburewa: karanta fayilai mara rubutu, sarrafa rafuffuka, hanyoyin sadarwa, bboye-boye, haukar hotunan/fayil, da damje.

Wahayi cewa I/O yake aiki da na gaida a bytes (Buffers) — da kuma yadda za a canza tsakanin Buffers da zanen da encoding daidai — yana da mahimmanci koda sa'ad da ka je waje ga rubutun tabbaci, kuma yake damje ga rafuffuka, tsarin fayil, da crypto.