add redis cache to competitions

internal/competition/server/server.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/jmoiron/sqlx"
 	_ "github.com/lib/pq"
+	"github.com/redis/go-redis/v9"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/reflection"
 )
@@ -26,8 +27,9 @@ const (
 
 type Server struct {
 	grpcServer *grpc.Server
-	config     *config.Config
-	db         *sqlx.DB
+	config      *config.Config
+	db          *sqlx.DB
+	redisClient *redis.Client
 }
 
 func New(cfg *config.Config) *Server {
@@ -43,6 +45,12 @@ func (s *Server) Start() error {
 	}
 	s.db = db
 
+	s.redisClient = redis.NewClient(&redis.Options{
+		Addr:     s.config.RedisAddr,
+		Password: s.config.RedisPassword,
+		DB:       s.config.RedisDB,
+	})
+
 	if err := s.registerGRPCServices(); err != nil {
 		return fmt.Errorf("failed to register gRPC services: %w", err)
 	}
@@ -63,7 +71,7 @@ func (s *Server) Start() error {
 }
 
 func (s *Server) registerGRPCServices() error {
-	compRepo := postgres.NewCompetitionRepository(s.db)
+	compRepo := postgres.NewCompetitionRepository(s.db, s.redisClient, s.config.CacheEnabled)
 	compService := service.NewCompetitionService(compRepo)
 	compHandler := grpcHandlers.NewCompetitionHandler(compService)
 
@@ -89,5 +97,11 @@ func (s *Server) Stop() {
 		}
 	}
 
+	if s.redisClient != nil {
+		if err := s.redisClient.Close(); err != nil {
+			log.Printf("failed to close redis client: %v", err)
+		}
+	}
+
 	log.Println("competition server stopped")
 }