first commit

cmd/ipecho/main.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"log/slog"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"ipecho/internal/buildinfo"
+	"ipecho/internal/clientip"
+	"ipecho/internal/config"
+	"ipecho/internal/httpapi"
+)
+
+func main() {
+	cfg, err := config.Load()
+	if err != nil {
+		logger := slog.New(slog.NewTextHandler(os.Stderr, nil))
+		logger.Error("invalid configuration", "error", err)
+		os.Exit(1)
+	}
+
+	logger := newLogger(cfg)
+	server := &http.Server{
+		Addr: cfg.Addr,
+		Handler: httpapi.NewWithLogger(clientip.Resolver{
+			TrustProxyHeaders: cfg.TrustProxyHeaders,
+			TrustedProxies:    cfg.TrustedProxyCIDRs,
+		}, logger),
+		ReadHeaderTimeout: cfg.ReadHeaderTimeout,
+		ReadTimeout:       cfg.ReadTimeout,
+		WriteTimeout:      cfg.WriteTimeout,
+		IdleTimeout:       cfg.IdleTimeout,
+		MaxHeaderBytes:    cfg.MaxHeaderBytes,
+	}
+
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
+	defer stop()
+
+	serverErrors := make(chan error, 1)
+	go func() {
+		logger.Info("server started",
+			"addr", cfg.Addr,
+			"trust_proxy_headers", cfg.TrustProxyHeaders,
+			"trusted_proxy_cidrs", cfg.TrustedProxyCIDRs,
+			"version", buildinfo.Version,
+			"commit", buildinfo.Commit,
+			"date", buildinfo.Date,
+		)
+		serverErrors <- server.ListenAndServe()
+	}()
+
+	select {
+	case <-ctx.Done():
+		logger.Info("server stopping")
+	case err := <-serverErrors:
+		if !errors.Is(err, http.ErrServerClosed) {
+			logger.Error("server stopped unexpectedly", "error", err)
+			os.Exit(1)
+		}
+
+		return
+	}
+
+	shutdownCtx, cancel := context.WithTimeout(context.Background(), cfg.ShutdownTimeout)
+	defer cancel()
+
+	if err := server.Shutdown(shutdownCtx); err != nil {
+		logger.Error("server shutdown failed", "error", err)
+		os.Exit(1)
+	}
+}
+
+func newLogger(cfg config.Config) *slog.Logger {
+	options := &slog.HandlerOptions{
+		Level: cfg.LogLevel,
+	}
+
+	if cfg.LogFormat == "json" {
+		return slog.New(slog.NewJSONHandler(os.Stdout, options))
+	}
+
+	return slog.New(slog.NewTextHandler(os.Stdout, options))
+}