마이크로서비스 아키텍처란? - 서비스는 어떻게 나누고 어떻게 통신하는가 | MSA 입문 Day 03

"I separated the services, so why did it become more complex?" Incorrectly implemented MSA is worse than a monolith. Today, we will properly learn everything from the core principles of MSA to service separation criteria and communication methods. 📌 What You Will Learn in This Course ✅ 4 Key Characteristics of Microservices Independent deployment, independent databases for each service, network communication, and a business function-centric organization Components that make up an MSA system: Client → API Gateway → Services → Kafka → DB ✅ How are services separated? - Separation by Business Domain vs. Separation by Technology Layer (What You Should Never Do) Conway's Law & Bounded Context The Two-Pizza Team Rule — The Appropriate Size of a Service ✅ Inter-Service Communication Methods Synchronous Communication (REST API, gRPC) — Immediate Response, but Risk of Fault Propagation Asynchronous Communication (Kafka) — Loose Coupling and Consequential Consistency REST Calls vs. Kafka Event Publishing in Code ✅ The Real Benefits and Costs of MSA Benefits: Independent Deployment, Scalability by Service, Fault Isolation, Technology Diversity Costs: Distributed Transactions, Operational Complexity, Testing Difficulties Most Common Mistakes: Distributed Monoliths, Nanoservices, Implementing Without Infrastructure --- 🗂️ Lecture Series: Mastering Microservices Architecture (20-Day Course) Day 01: What Are Microservices? Day 02: What Is Monolithic Architecture? Day 03: What Is Microservices Architecture? ← Current Video Day 04: Domain-Driven Design (DDD) Basics (Next Video) --- 📌 Timestamps 00:00 Intro 01:10 4 Key Characteristics of MSA 03:10 MSA Architecture Structure 04:50 MSA System Components (Client → DB) 06:10 Service Separation Criteria — Business Domain 08:00 Appropriate Service Sizing 09:30 Comparison of Incorrect Separation vs. Correct Separation 11:00 Synchronous Communication: REST & gRPC 12:50 Asynchronous Communication: Kafka & Consequential Consistency 14:20 REST vs. Kafka in Code 15:30 The Real Benefits of MSA 17:00 Complexity Brought by MSA 18:20 Practical Comparison of Monolith vs. MSA 19:30 Steps for Successful MSA Adoption 21:00 Common Mistakes (Beware of Distributed Monoliths!) 22:30 Summary of Today's Lecture & Day 04 Preview --- #Microservices #MSA #ServiceSeparation #Kafka #RESTAPI #BackendDevelopment #SoftwareArchitecture #DDD #SpringBoot #Developer