Spring Boot & Microservices: Free Skill Evaluation

Why Spring? Spring Framework Architecture Spring Boot Spring Boot 4 Project Structure IoC Dependency Injection Constructor Injection Beans Bean Scope Bean Lifecycle Component Scanning @Configuration @Bean Conditional Beans Concepts application.properties YAML Profiles Environment Variables ConfigurationProperties Secret Separation DispatcherServlet Controllers Request Mapping RequestBody RequestParam PathVariable ResponseEntity Validation Filters Interceptors REST Principles Resource Design HTTP Semantics Status Codes DTO Design Input Validation Error Responses Global Exception Handling Pagination Sorting Filtering Search API Versioning Idempotent APIs OpenAPI Swagger PostgreSQL Data Modeling JPA Fundamentals Entity Repository Entity Relationships Lazy Loading Eager Loading Cascades Orphan Removal Persistence Context Dirty Checking JPQL Native Queries N+1 Query Problem Fetch Join Entity Graph Concepts Batch Fetching Projection Database Indexing Query Plans @Transactional ACID Transaction Boundaries Propagation Isolation Rollback Optimistic Locking Pessimistic Locking Lost Update Deadlocks Authentication Authorization Spring Security Architecture SecurityFilterChain Password Encoding Roles Authorities Method Security JWT Structure Access Tokens Refresh Tokens Expiration Token Validation Signing Keys Rotation Concepts Revocation OAuth2 Fundamentals Resource Server OAuth Client OpenID Connect Authorization Code PKCE Client Credentials Scopes Identity Provider Concepts Broken Access Control Object-Level Authorization SQL Injection CSRF CORS Rate Limiting Secrets Sensitive Logging Security Headers Why Start Modular? What Is a Microservice? Monolith vs Microservices When Microservices Make Sense When They Do Not Service Autonomy Independent Deployment Database per Service Loose Coupling Bounded Context Domain Boundaries Business Capability Decomposition DDD Boundaries Data Ownership Shared Database Anti-Pattern Service-to-Service REST RestClient HTTP Interface Clients WebClient Awareness gRPC Support Timeout Retry Exponential Backoff Jitter Connection Pooling Partial Failure Circuit Breaker Bulkhead Rate Limiter Time Limiter Resilience4j Concepts Spring Cloud Circuit Breaker Gateway Pattern Spring Cloud Gateway Routing Request Filters Response Filters Correlation IDs Configuration Per Environment Spring Cloud Config Git-backed Configuration Concepts Kubernetes ConfigMaps Kubernetes Secrets External Secrets Concepts Service Discovery Concepts Client-Side Discovery Server-Side Discovery Kubernetes-Native Discovery Events Commands vs Events Event Producer Event Consumer Event Contract Event Schema Evolution Eventual Consistency Kafka Architecture Broker Topic Partition Producer Consumer Consumer Group Offset Message Keys Ordering Replication Concepts Serialization Delivery Semantics KafkaTemplate @KafkaListener Consumer Configuration Producer Configuration Acknowledgements Error Handling Dead-Letter Topics Retry Topic Design Ordering vs Retry Tradeoff Duplicate Requests Duplicate Events Idempotency Key Idempotent Consumer Unique Constraints Processed Event Registry Why @Transactional Doesn't Span Microservices Two-Phase Commit Concepts Saga Choreography Orchestration Compensation Dual Write Problem Transactional Outbox Inbox Pattern Deduplication CDC-based Outbox Concepts Cache Fundamentals Cache-Aside TTL Eviction Cache Invalidation Cache Stampede Distributed Lock Concepts Redis-backed Session Concepts Async Workflows Scheduled Jobs Job State Idempotency Logs Metrics Traces Structured Logging Spring Boot Actuator Micrometer Concepts Prometheus Concepts Grafana Concepts OpenTelemetry Distributed Tracing Liveness Readiness Startup Health Dependency Health Testing Pyramid JUnit Mockito Spring Boot Tests MockMvc Repository Tests Integration Tests Testcontainers Kafka Integration Tests Security Tests API Contracts Consumer-Driven Contracts Spring Cloud Contract Concepts Breaking Changes Microservice Test Strategy P50 / P95 / P99 Throughput CPU Memory Database Network Thread Pools Connection Pools Indexes Slow Queries Explain Plan Connection Pool Exhaustion N+1 Batch Operations Keyset Pagination Concepts Heap Garbage Collection Thread Dumps Heap Dumps CPU Profiling Memory Leak Investigation Images Containers Dockerfile Multi-Stage Build Networking Volumes Docker Compose Kubernetes Architecture Pods Deployments Services ConfigMaps Liveness Probes Readiness Probes Requests / Limits Horizontal Scaling Rolling Updates Ingress / Gateway Concepts Kubernetes Service Discovery IAM EC2 S3 RDS Load Balancing Auto Scaling CloudWatch Secrets Management Container Deployment EKS Awareness Managed Kafka Awareness Continuous Integration Continuous Delivery GitHub Actions Jenkins Concepts Artifact Repository Environment Promotion Rolling Blue/Green Canary Feature Flags Zero Trust Concepts Service Identity mTLS Concepts Token Propagation Service-to-Service Authorization Least Privilege Why Rate Limit? Token Bucket Fixed Window Sliding Window Concepts Gateway-Level Rate Limiting CAP Theorem Consistency Availability Partition Tolerance Strong Consistency Quorum Concepts Clock / Time Challenges Duplicate Messages Backpressure Microservices Anti-Patterns Microservice System Design Design E-Commerce Microservices Design Payment Platform Design Booking Platform Production Incident Engineering