Context, Handler, Router, and Middleware

[FumingPower3925]

Summary

Core application-level abstractions: request context, handler types, router with pattern matching, and middleware chain.

Context

• Zero-copy contract:
  • Body() returns volatile slice (only valid during handler execution)
  • BodyBytes() returns a copy (safe to store/pass around)
• Methods: Method(), Path(), Param(name), Query(name), Header(name), SetHeader(), Status(), JSON(), String(), Bytes(), Stream()
• Port from old_celeris/pkg/celeris/context.go

Handler

type Handler interface {
    Handle(ctx *Context)
}
type HandlerFunc func(ctx *Context)

Router

• Static routes: /users, /health
• Parameter routes: /users/:id, /posts/:id/comments/:cid
• Wildcard routes: /static/*filepath
• Route groups: server.Group("/api/v1")
• Method-specific: GET(), POST(), PUT(), DELETE(), PATCH(), HEAD(), OPTIONS()
• Port from old_celeris/pkg/celeris/router.go

Middleware

• Chain execution: middleware1 → middleware2 → handler → middleware2 → middleware1
• ctx.Next() to continue chain, ctx.Abort() to stop
• Built-in middleware:
  • Logger — request logging with duration
  • Recovery — panic recovery with stack trace
  • CORS — configurable cross-origin headers
  • RequestID — UUID per request via X-Request-ID
  • Compress — gzip/deflate response compression
  • RateLimit — token bucket per-IP rate limiting
  • Health — /health endpoint
  • Timeout — per-request timeout with context cancellation
• Port from old_celeris/pkg/celeris/middleware.go

stdlib Bridge

// Adapt wraps an http.Handler for use with Celeris
func Adapt(h http.Handler) HandlerFunc

Tests

• Context: all getter/setter methods
• Context: zero-copy contract (Body() volatile, BodyBytes() safe)
• Router: static, param, wildcard patterns
• Router: route groups with prefix
• Router: method routing
• Middleware: execution order (pre-handler, post-handler)
• Middleware: Abort() stops chain
• Each built-in middleware individually
• Adapt() bridge with http.Handler

SDD Reference

Sections 11.4, 11.5

Dependencies

Depends on #3, #4

[FumingPower3925]

Implemented: 34+ Context methods, radix trie router with :param/*catchAll, pre-composed middleware chains, bridge adapter. Built-in middleware moved to goceleris/middlewares by design.