Use when building web services. Keywords: web server, HTTP, REST API, GraphQL, WebSocket, axum, actix, warp, rocket, tower, hyper, reqwest, middleware, router, handler, extractor, state management, authentication, authorization, JWT, session, cookie, CORS, rate limiting, web 开发, HTTP 服务, API 设计, 中间件

Web Domain Layer 3: Domain Constraints Domain Constraints → Design Implications Domain Rule Design Constraint Rust Implication Stateless HTTP No request local globals State in extractors Concurrency Handle many connections Async, Send + Sync Latency SLA Fast response Efficient ownership Security Input validation Type safe extractors Observability Request tracing tracing + tower layers Critical Constraints Async by Default State Management Request Lifecycle Trace Down ↓ From constraints to design (Layer 2): Framework Comparison Framework Style Best For axum Functional, tower Modern APIs actix web Actor based High performance warp Filter composition Composable APIs rocket Macro driven Rapid development Key Crates Purpose Crate HTTP server axum, actix web HTTP client reqwest JSON serde json Auth/JWT jsonwebtoken Session tower sessions Database sqlx, diesel Middleware tower Design Patterns Pattern Purpose Implementation Extractors Request parsing State(db) , Json(payload) Error response Unified errors impl IntoResponse Middleware Cross cutting Tower layers Shared state App config Arc<AppState Code Pattern: Axum Handler Common Mistakes Mistake Domain Violation Fix Blocking in handler Latency spike spawn blocking Rc in state Not Send + Sync Use Arc No validation Security risk Type safe extractors No error response Bad UX IntoResponse impl Trace to Layer 1 Constraint Layer 2 Pattern Layer 1 Implementation Async handlers Async/await tokio runtime Thread safe state Shared state Arc<T , Arc<RwLock<T Request lifecycle Extractors Ownership via From<Request Middleware Tower layers Trait based composition Related Skills When See Async patterns m07 concurrency State management m02 resource Error handling m06 error handling Middleware design m12 lifecycle

domain-web