Feat: Backend scaffolding and local dev stack

Backend/internal/bootstrap/bootstrap.go

@@ -0,0 +1,85 @@
+// Path: Backend/internal/bootstrap/bootstrap.go
+
+package bootstrap
+
+import (
+	"log/slog"
+	"os"
+	"strings"
+
+	"moku-backend/internal/buildinfo"
+	"moku-backend/internal/cache"
+	"moku-backend/internal/config"
+	"moku-backend/internal/database"
+)
+
+type App struct {
+	ServiceName string
+	Config      *config.Config
+	Logger      *slog.Logger
+	BuildInfo   buildinfo.Info
+	Database    *database.DB
+	Cache       *cache.Client
+}
+
+func New(serviceName string) (*App, error) {
+	cfg := config.Load()
+	logger := newLogger(cfg)
+
+	db, err := database.NewPostgres(cfg.PostgresURL)
+	if err != nil {
+		return nil, err
+	}
+
+	valkey, err := cache.NewValkey(cfg.ValkeyURL)
+	if err != nil {
+		db.Close()
+		return nil, err
+	}
+
+	return &App{
+		ServiceName: serviceName,
+		Config:      cfg,
+		Logger:      logger.With("service", serviceName),
+		BuildInfo:   buildinfo.Current(),
+		Database:    db,
+		Cache:       valkey,
+	}, nil
+}
+
+func (a *App) Close() error {
+	var closeErr error
+
+	if a.Cache != nil {
+		if err := a.Cache.Close(); err != nil {
+			closeErr = err
+		}
+	}
+
+	if a.Database != nil {
+		a.Database.Close()
+	}
+
+	return closeErr
+}
+
+func newLogger(cfg *config.Config) *slog.Logger {
+	level := slog.LevelInfo
+
+	switch strings.ToLower(cfg.LogLevel) {
+	case "debug":
+		level = slog.LevelDebug
+	case "warn":
+		level = slog.LevelWarn
+	case "error":
+		level = slog.LevelError
+	}
+
+	options := &slog.HandlerOptions{Level: level}
+
+	if cfg.IsDevelopment() {
+		return slog.New(slog.NewTextHandler(os.Stdout, options))
+	}
+
+	return slog.New(slog.NewJSONHandler(os.Stdout, options))
+}