Lecture on Microservices - Overview and Best Practices <!-- Example Notes for a Lecture on Microservices Overview --> ## Introduction to Microservices - Trending technology for today's industries to create/deploy applications - Gives complete insight to get started with Microservices ## Agenda - Introduction to Microservices - Definition, benefits, differences from other architectures - Microservices with Docker and Spring Boot - Comparing microservices with service-oriented architectures - Microservices vs APIs - Design patterns in microservices - Tools to use with microservices - Securing microservices - Top interview questions on microservices ## Monolithic vs. Microservices ### Monolithic Architecture - Entire software composed in a single piece, designed to be self-contained - Interconnected and interdependent components - Hard to scale, maintain, and update ### Issues with Monolithic Architecture - Complex Applications: Hard to understand, modify; development slows, code quality declines - Slow Development: Larger codebase slows down IDEs, makes development slower - Blocked Continuous Deployment: Need to redeploy entire app to update one component - Unscalable: High memory/CPU consumption, components scaled together - Unreliable: One module bug can bring down entire app - Inflexible: Difficult to adopt new frameworks/technologies ## Introduction to Microservices - Architectural style structuring applications as collections of small autonomous services modeled around business domains - Each service is a self-contained process; large apps broken down, each focusing on a single business capability ### Microservices Architecture - Small, independent, loosely coupled services - Each service is its own code base, managed by a small dev team, deployable independently - Services responsible for their own data - Communication through APIs ### Key Features - Small focused services: Easier to manage and develop - Loosely coupled: Development and deployment quicker and easier - Language neutral: Services can use different technologies - Bounded context: Each service's implementation details hidden from others ## Microservices vs. Monolithic Architectures - Independent development: Teams can build, test, deploy services individually - Independent deployment: Less risky, manage bug fixes/features without redeploying entire app - Fault isolation: Failures in one service won’t bring down the entire app - Scalability: Scale services independently ## Companies Using Microservices - Amazon, Netflix, SoundCloud, Twitter, Uber, PayPal ## Hands-on with Spring Boot and Microservices ### Environment Setup - Tools: Eclipse IDE, Maven, Spring Boot - Projects: Doctor, Diagnosis, Patient microservices - Configuration: Setup different packages, dependencies, ports - Commands: run as spring boot app, localhost to access services ### Compare Monolithic vs Microservices Application Example - Example of e-commerce website - Monolithic tightly coupled, difficult to manage - Microservices: Customer, Product, Cart services independently manageable ## Microservices with Spring Boot and Docker - Building a top sports brand application - Services: Eureka Server, Item catalog service, Edge service - Eureka service: Registry of services - Item catalog service: Provides sports brands - Edge service: Filters top sports brands ### Commands and Tools - Docker: docker pull, docker run, docker ps - Docker Hub: Repository for Docker images - Docker Compose: Configure and run multi-container Docker applications ## Final Thoughts on Microservices - Benefits: Speed, scalability, team autonomy - Challenges: Complexity, debugging, configuration management - Microservices require appropriate tools, patterns, security measures to be implemented correctly