implement payroll generator v0.9

service/data-hub/business-engine/cmd/api/main.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"business-engine/internal/config"
+	"log/slog"
+	"os"
+)
+
+func main() {
+	handler := slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
+		Level: slog.LevelDebug,
+	})
+
+	logger := slog.New(handler)
+	slog.SetDefault(logger)
+
+	cfg, err := config.Load()
+	if err != nil {
+		logger.Error("failed to load configuration", "error", err)
+		os.Exit(1)
+	}
+
+	server, err := NewServer(cfg, logger)
+	if err != nil {
+		logger.Error("failed to create server", "error", err)
+		os.Exit(1)
+	}
+
+	server.Start()
+}

service/data-hub/business-engine/cmd/api/server.go

@@ -0,0 +1,89 @@
+package main
+
+import (
+	"business-engine/internal/config"
+	"business-engine/internal/database"
+	"business-engine/internal/payroll"
+	"context"
+	"log/slog"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+// Server contains all dependencies of the application
+type Server struct {
+	config *config.Config
+	logger *slog.Logger
+	db     *pgxpool.Pool
+	router *http.ServeMux
+}
+
+// NewServer constructs a new server
+func NewServer(cfg *config.Config, logger *slog.Logger) (*Server, error) {
+	dbpool, err := pgxpool.New(context.Background(), cfg.DatabaseURL)
+	if err != nil {
+		logger.Error("failed to connect to database", "error", err)
+		os.Exit(1)
+	}
+
+	server := &Server{
+		config: cfg,
+		logger: logger,
+		db:     dbpool,
+		router: http.NewServeMux(),
+	}
+
+	server.setupRoutes()
+
+	return server, nil
+}
+
+// setupRoutes initializes all routes and handlers
+func (s *Server) setupRoutes() {
+	employeeRepo := database.New(s.db)
+	employeeService := payroll.NewService(employeeRepo, s.logger)
+	employeeHandler := payroll.NewEmployeeHandler(*employeeService, s.logger)
+
+	s.router.HandleFunc("GET /health", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte("OK"))
+	})
+
+	s.router.HandleFunc("GET /api/v1/employees", employeeHandler.ListEmployees)
+
+	s.router.HandleFunc("GET /api/v1/payroll", employeeHandler.RunPayroll)
+}
+
+func (s *Server) Start() {
+	httpServer := &http.Server{
+		Addr:    ":" + s.config.Port,
+		Handler: s.router,
+	}
+
+	go func() {
+		s.logger.Info("server starting", "port", s.config.Port)
+		if err := httpServer.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			s.logger.Error("server failed to start", "error", err)
+			os.Exit(1)
+		}
+	}()
+
+	stop := make(chan os.Signal, 1)
+	signal.Notify(stop, os.Interrupt, syscall.SIGTERM)
+	<-stop
+
+	s.logger.Info("shutting down server gracefully")
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := httpServer.Shutdown(ctx); err != nil {
+		s.logger.Error("server shutdown failed", "error", err)
+	} else {
+		s.logger.Info("server stopped")
+	}
+}