docs(10_Wiki): Topic_Business/General/Graphic/Programming을 Topics/ 하위로 이동

최상위 10_Wiki/Topic_*였던 4개 카테고리 폴더를 10_Wiki/Topics/Topic_* 로 재배치.
콘텐츠 변경 없음(순수 폴더 이동) — Topics/ 하위 나머지 폴더는 이미 지난 커밋에서
전부 정리된 상태(잔존 항목은 에이전트 운영 상태 및 사용자가 보존을 요청한
업데이트0615/무제 3.canvas 뿐).

10_Wiki/Topics/Topic_Programming/Programming & Language/스트림Stream.md

@@ -0,0 +1,142 @@
+---
+id: wiki-2026-0508-스트림-stream
+title: 스트림(Stream)
+category: 10_Wiki/Topics
+status: verified
+canonical_id: self
+aliases: [stream, streaming]
+duplicate_of: none
+source_trust_level: A
+confidence_score: 0.95
+verification_status: applied
+tags: [stream, async, io]
+raw_sources: []
+last_reinforced: 2026-05-10
+github_commit: pending
+tech_stack:
+  language: typescript
+  framework: nodejs
+---
+
+# 스트림(Stream)
+
+## 매 한 줄
+> **"매 데이터를 chunk 단위로 점진 전달한다"**. 매 entire payload 를 buffer 에 fully load 하지 않고, 매 사용 가능한 시점마다 chunk 를 yield → 매 memory footprint 감소 + first-byte latency 개선. 매 modern web (Server-Sent Events · LLM token streaming · HTTP/2 push) 의 backbone.
+
+## 매 핵심
+
+### 매 Stream 의 종류
+- **Readable**: pull-based source (file read, HTTP response).
+- **Writable**: push-based sink (file write, response.write).
+- **Duplex**: read + write (TCP socket).
+- **Transform**: read → mutate → write (gzip, JSON.parse).
+
+### 매 동작 모델
+- **Chunk + backpressure**: consumer slow → producer pause (highWaterMark).
+- **Object mode**: chunk 가 raw bytes 가 아닌 object.
+- **Pipe**: source.pipe(transform).pipe(sink) chain.
+
+### 매 응용
+1. LLM token streaming (Claude · GPT-5 의 SSE response).
+2. Large file upload/download (Multipart, S3 multipart).
+3. Real-time analytics (Kafka consumer).
+
+## 💻 패턴
+
+### Web Streams API (cross-platform)
+```typescript
+const response = await fetch("/api/llm");
+const reader = response.body!.pipeThrough(new TextDecoderStream()).getReader();
+while (true) {
+  const { value, done } = await reader.read();
+  if (done) break;
+  process.stdout.write(value);
+}
+```
+
+### Async iteration over Node stream
+```typescript
+import { createReadStream } from "node:fs";
+const stream = createReadStream("big.log", { encoding: "utf-8" });
+for await (const chunk of stream) {
+  console.log(`got ${chunk.length} chars`);
+}
+```
+
+### Transform stream — gzip on the fly
+```typescript
+import { pipeline } from "node:stream/promises";
+import { createReadStream, createWriteStream } from "node:fs";
+import { createGzip } from "node:zlib";
+await pipeline(createReadStream("input.txt"), createGzip(), createWriteStream("output.gz"));
+```
+
+### Server-Sent Events (LLM token stream)
+```typescript
+// Hono / Bun
+import { streamSSE } from "hono/streaming";
+app.get("/chat", c => streamSSE(c, async stream => {
+  for await (const tok of llm.generate(prompt)) {
+    await stream.writeSSE({ data: tok });
+  }
+}));
+```
+
+### ReadableStream from generator
+```typescript
+function makeStream<T>(gen: AsyncGenerator<T>) {
+  return new ReadableStream<T>({
+    async pull(controller) {
+      const { value, done } = await gen.next();
+      done ? controller.close() : controller.enqueue(value);
+    }
+  });
+}
+```
+
+### Backpressure handling
+```typescript
+const writable = createWriteStream("out.bin");
+function writeChunk(buf: Buffer) {
+  if (!writable.write(buf)) {
+    return new Promise<void>(res => writable.once("drain", res));
+  }
+  return Promise.resolve();
+}
+```
+
+## 매 결정 기준
+| 상황 | Approach |
+|---|---|
+| Browser fetch streaming | Web Streams API (`response.body`) |
+| Node.js file/network | `node:stream` + async iter |
+| LLM token stream | SSE or chunked transfer |
+| Massive object pipeline | object mode + Transform |
+| Cross-runtime (Bun/Deno) | Web Streams (standard) |
+
+**기본값**: Web Streams API + async iteration.
+
+## 🔗 Graph
+- 부모: [[Nodejs 성능 최적화 및 디버깅]]
+- Adjacent: [[API 응답 및 에러 핸들링 아키텍처]]
+- 응용: [[Server Architecture]]
+
+## 🤖 LLM 활용
+**언제**: streaming chat UI · large file async processing · backpressure debug.
+**언제 X**: small payload (<1MB) — buffering 이 simpler.
+
+## ❌ 안티패턴
+- **Concat all chunks before yielding**: stream 의 의미 무효화.
+- **Ignore backpressure**: producer 가 consumer 추월 → memory blow up.
+- **No error propagation in pipe**: 한 stage error 가 silent.
+- **Sync transform on huge object**: event loop block.
+
+## 🧪 검증 / 중복
+- Verified (Node.js docs · WHATWG Streams Standard).
+- 신뢰도 A.
+
+## 🕓 Changelog
+| 날짜 | 변경 |
+|---|---|
+| 2026-05-08 | Phase 1 |
+| 2026-05-10 | Manual cleanup — Stream API 패턴 정리 |