go-web-apis

# Go Web APIs Skill

Build production-ready REST APIs with Go's net/http and popular frameworks.

## Overview

Complete guide for building secure, performant web APIs including routing, middleware, authentication, and best practices.

## Parameters

| Parameter | Type | Required | Default | Description |
|-----------|------|----------|---------|-------------|
| framework | string | no | "stdlib" | Framework: "stdlib", "gin", "echo", "chi" |
| auth_type | string | no | "jwt" | Auth method: "jwt", "api-key", "oauth" |
| include_openapi | bool | no | false | Generate OpenAPI spec |

## Core Topics

### HTTP Handler Pattern
```go
type Server struct {
    db     *sql.DB
    logger *slog.Logger
}

func (s *Server) handleGetUser() http.HandlerFunc {
    return func(w http.ResponseWriter, r *http.Request) {
        id := chi.URLParam(r, "id")

        user, err := s.db.GetUser(r.Context(), id)
        if err != nil {
            if errors.Is(err, sql.ErrNoRows) {
                http.Error(w, "user not found", http.StatusNotFound)
                return
            }
            s.logger.Error("get user", "error", err)
            http.Error(w, "internal error", http.StatusInternalServerError)
            return
        }

        w.Header().Set("Content-Type", "application/json")
        json.NewEncoder(w).Encode(user)
    }
}
```

### Middleware
```go
func LoggingMiddleware(logger *slog.Logger) func(http.Handler) http.Handler {
    return func(next http.Handler) http.Handler {
        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
            start := time.Now()
            ww := &responseWriter{ResponseWriter: w, status: 200}

            defer func() {
                logger.Info("request",
                    "method", r.Method,
                    "path", r.URL.Path,
                    "status", ww.status,
                    "duration", time.Since(start),
                )
            }()

            next.ServeHTTP(ww, r)
        })
    }
}