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).
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+---
+id: wiki-2026-0508-publish-subscribe-model
+title: Publish-Subscribe Model
+category: 10_Wiki/Topics
+status: verified
+canonical_id: self
+aliases: [Pub-Sub, Pub/Sub, Topic-Based Messaging]
+duplicate_of: none
+source_trust_level: A
+confidence_score: 0.95
+verification_status: applied
+tags: [messaging, eda, distributed-systems, pattern]
+raw_sources: []
+last_reinforced: 2026-05-10
+github_commit: pending
+tech_stack:
+  language: python
+  framework: kafka-redis-nats
+---
+
+# Publish-Subscribe Model
+
+## 매 한 줄
+> **"매 publisher 매 subscribers 매 모름 — 매 topic / channel 매 통해 매 decoupled broadcast"**. 1987 ISIS Toolkit 매 origin, 매 today Kafka / Redis Pub/Sub / NATS / Google Pub/Sub / AWS SNS 매 ubiquitous backbone.
+
+## 매 핵심
+
+### 매 model variants
+- **Topic-based**: 매 logical channel name (e.g. `orders.created`).
+- **Content-based**: 매 message attributes 매 filter — 매 RabbitMQ headers exchange.
+- **Type-based**: 매 message class hierarchy.
+- **Hybrid**: 매 topic + filter (NATS subject wildcards `orders.*.created`).
+
+### 매 delivery semantics
+- **At-most-once**: fire-and-forget (Redis Pub/Sub).
+- **At-least-once**: ack required (Kafka, SQS).
+- **Exactly-once**: 매 idempotent + transactional (Kafka EOS, Pulsar).
+
+### 매 응용
+1. Event-driven microservices (orders → fulfillment, billing, notifications).
+2. Real-time dashboards (Grafana Live, websocket fanout).
+3. CDC (Debezium → Kafka → consumers).
+4. IoT telemetry (MQTT — pub-sub variant).
+
+## 💻 패턴
+
+### In-process pub-sub (Python)
+```python
+from collections import defaultdict
+from typing import Callable
+
+class Bus:
+    def __init__(self):
+        self.subs: dict[str, list[Callable]] = defaultdict(list)
+    def subscribe(self, topic, fn): self.subs[topic].append(fn)
+    def publish(self, topic, msg):
+        for fn in self.subs[topic]:
+            fn(msg)
+
+bus = Bus()
+bus.subscribe("user.created", lambda u: print(f"welcome {u}"))
+bus.publish("user.created", "alice")
+```
+
+### Redis Pub/Sub
+```python
+import redis, json
+r = redis.Redis()
+
+# Publisher
+r.publish("orders.created", json.dumps({"id": 42, "total": 99}))
+
+# Subscriber
+ps = r.pubsub()
+ps.subscribe("orders.*")
+for msg in ps.listen():
+    if msg["type"] == "pmessage":
+        handle(json.loads(msg["data"]))
+```
+
+### Kafka producer/consumer (Python)
+```python
+from confluent_kafka import Producer, Consumer
+
+p = Producer({"bootstrap.servers": "localhost:9092"})
+p.produce("orders", key="42", value=b'{"total":99}')
+p.flush()
+
+c = Consumer({
+    "bootstrap.servers": "localhost:9092",
+    "group.id": "fulfillment",
+    "auto.offset.reset": "earliest",
+})
+c.subscribe(["orders"])
+while True:
+    msg = c.poll(1.0)
+    if msg and not msg.error():
+        process(msg.value())
+        c.commit(msg)
+```
+
+### NATS with subject wildcards
+```python
+import nats, asyncio
+
+async def main():
+    nc = await nats.connect("nats://localhost:4222")
+    async def cb(msg): print(msg.subject, msg.data)
+    await nc.subscribe("orders.*.created", cb=cb)
+    await nc.publish("orders.US.created", b'{"id":42}')
+    await asyncio.sleep(1)
+
+asyncio.run(main())
+```
+
+### Google Cloud Pub/Sub
+```python
+from google.cloud import pubsub_v1
+
+publisher = pubsub_v1.PublisherClient()
+topic = publisher.topic_path("proj", "orders")
+publisher.publish(topic, b'{"id":42}', region="us-east1")
+
+sub = pubsub_v1.SubscriberClient()
+sub_path = sub.subscription_path("proj", "fulfillment-sub")
+def cb(msg): handle(msg.data); msg.ack()
+sub.subscribe(sub_path, callback=cb).result()
+```
+
+### AsyncAPI schema (governance, 2026)
+```yaml
+asyncapi: 3.0.0
+channels:
+  ordersCreated:
+    address: orders.created
+    messages:
+      OrderCreated:
+        payload:
+          type: object
+          properties:
+            id: {type: integer}
+            total: {type: number}
+```
+
+## 매 결정 기준
+| 상황 | Approach |
+|---|---|
+| 매 in-process | Bus / EventEmitter |
+| 매 ephemeral, low-latency | Redis Pub/Sub / NATS |
+| 매 durable, replay 필요 | Kafka / Pulsar |
+| 매 cloud-native, managed | Google Pub/Sub / AWS SNS+SQS |
+| 매 IoT / mobile | MQTT |
+| 매 fan-in-out, transform | Kafka Streams / Pulsar Functions |
+
+**기본값**: 매 production EDA — Kafka. 매 simple/ephemeral — NATS.
+
+## 🔗 Graph
+- 부모: [[Event-Driven Architecture]]
+- 변형: [[Observer Pattern]] · [[Event Bus]]
+- 응용: [[Event Sourcing]] · [[CQRS]] · [[CDC]]
+- Adjacent: [[Kafka]] · [[NATS]] · [[Redis]] · [[MQTT]]
+
+## 🤖 LLM 활용
+**언제**: 매 schema design (AsyncAPI generation), 매 consumer code scaffolding, 매 dead-letter analysis.
+**언제 X**: 매 broker selection 매 trust 의 X — workload metrics 직접 측정.
+
+## ❌ 안티패턴
+- **Sync pub-sub**: 매 publisher block on slow subscriber — 매 async / queue 사용.
+- **No schema**: 매 consumer breakage — Avro/Protobuf + registry 필수.
+- **Topic explosion**: 매 user-per-topic — 매 millions of topics, broker 죽음. 매 partition / filter 사용.
+- **Duplicate semantics**: 매 at-least-once 인데 매 idempotency 없음 — duplicate processing.
+
+## 🧪 검증 / 중복
+- Verified (Eugster et al. — "The Many Faces of Publish/Subscribe" 2003; Kafka docs).
+- 신뢰도 A.
+
+## 🕓 Changelog
+| 날짜 | 변경 |
+|---|---|
+| 2026-05-08 | Phase 1 |
+| 2026-05-10 | Manual cleanup — full pub-sub pattern entry |