Add project scaffolding with fx DI, SQLite migrations, and healthcheck

- go.mod with git.eeqj.de/sneak/chat module
- internal packages: globals, logger, config, db, healthcheck, middleware, handlers, server
- SQLite database with embedded migration system (schema_migrations tracking)
- Migration 001: schema_migrations table
- Migration 002: channels table
- Config with chat-specific vars (MAX_HISTORY, SESSION_TIMEOUT, MAX_MESSAGE_SIZE, MOTD, SERVER_NAME, FEDERATION_KEY)
- Healthcheck endpoint at /.well-known/healthcheck.json
- Makefile, .gitignore
- cmd/chatd/main.go entry point

internal/middleware/middleware.go

@@ -0,0 +1,131 @@
+package middleware
+
+import (
+	"log/slog"
+	"net"
+	"net/http"
+	"time"
+
+	"git.eeqj.de/sneak/chat/internal/config"
+	"git.eeqj.de/sneak/chat/internal/globals"
+	"git.eeqj.de/sneak/chat/internal/logger"
+	basicauth "github.com/99designs/basicauth-go"
+	"github.com/go-chi/chi/middleware"
+	"github.com/go-chi/cors"
+	metrics "github.com/slok/go-http-metrics/metrics/prometheus"
+	ghmm "github.com/slok/go-http-metrics/middleware"
+	"github.com/slok/go-http-metrics/middleware/std"
+	"github.com/spf13/viper"
+	"go.uber.org/fx"
+)
+
+type MiddlewareParams struct {
+	fx.In
+	Logger  *logger.Logger
+	Globals *globals.Globals
+	Config  *config.Config
+}
+
+type Middleware struct {
+	log    *slog.Logger
+	params *MiddlewareParams
+}
+
+func New(lc fx.Lifecycle, params MiddlewareParams) (*Middleware, error) {
+	s := new(Middleware)
+	s.params = &params
+	s.log = params.Logger.Get()
+	return s, nil
+}
+
+func ipFromHostPort(hp string) string {
+	h, _, err := net.SplitHostPort(hp)
+	if err != nil {
+		return ""
+	}
+	if len(h) > 0 && h[0] == '[' {
+		return h[1 : len(h)-1]
+	}
+	return h
+}
+
+type loggingResponseWriter struct {
+	http.ResponseWriter
+	statusCode int
+}
+
+func NewLoggingResponseWriter(w http.ResponseWriter) *loggingResponseWriter {
+	return &loggingResponseWriter{w, http.StatusOK}
+}
+
+func (lrw *loggingResponseWriter) WriteHeader(code int) {
+	lrw.statusCode = code
+	lrw.ResponseWriter.WriteHeader(code)
+}
+
+func (s *Middleware) Logging() 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()
+			lrw := NewLoggingResponseWriter(w)
+			ctx := r.Context()
+			defer func() {
+				latency := time.Since(start)
+				s.log.InfoContext(ctx, "request",
+					"request_start", start,
+					"method", r.Method,
+					"url", r.URL.String(),
+					"useragent", r.UserAgent(),
+					"request_id", ctx.Value(middleware.RequestIDKey).(string),
+					"referer", r.Referer(),
+					"proto", r.Proto,
+					"remoteIP", ipFromHostPort(r.RemoteAddr),
+					"status", lrw.statusCode,
+					"latency_ms", latency.Milliseconds(),
+				)
+			}()
+
+			next.ServeHTTP(lrw, r)
+		})
+	}
+}
+
+func (s *Middleware) CORS() func(http.Handler) http.Handler {
+	return cors.Handler(cors.Options{
+		AllowedOrigins:   []string{"*"},
+		AllowedMethods:   []string{"GET", "POST", "PUT", "DELETE", "OPTIONS"},
+		AllowedHeaders:   []string{"Accept", "Authorization", "Content-Type", "X-CSRF-Token"},
+		ExposedHeaders:   []string{"Link"},
+		AllowCredentials: false,
+		MaxAge:           300,
+	})
+}
+
+func (s *Middleware) Auth() func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			s.log.Info("AUTH: before request")
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+func (s *Middleware) Metrics() func(http.Handler) http.Handler {
+	mdlw := ghmm.New(ghmm.Config{
+		Recorder: metrics.NewRecorder(metrics.Config{}),
+	})
+	return func(next http.Handler) http.Handler {
+		return std.Handler("", mdlw, next)
+	}
+}
+
+func (s *Middleware) MetricsAuth() func(http.Handler) http.Handler {
+	return basicauth.New(
+		"metrics",
+		map[string][]string{
+			viper.GetString("METRICS_USERNAME"): {
+				viper.GetString("METRICS_PASSWORD"),
+			},
+		},
+	)
+}