Enhance dashboard service with widget caching and improved query handling

- Introduced a new `widgetCache` structure to manage caching for various dashboard widgets, improving performance and reducing redundant data retrieval.
- Updated the `ClosingSoon` and `Trend` methods in the service to utilize the new caching mechanism, ensuring efficient data access and reducing load on the database.
- Enhanced the `NoticeTypes` and `Countries` methods to implement caching, further optimizing the dashboard's responsiveness.
- Added a new `searchListCache` implementation in the tender service to cache search results, improving the efficiency of tender searches and reducing database load.
- Implemented robust error handling and logging for cache operations, ensuring better visibility into potential issues.

This update significantly enhances the performance and scalability of the dashboard and tender services by integrating effective caching strategies, leading to improved user experience and resource management.

internal/dashboard/repository.go

@@ -439,12 +439,25 @@ func (r *repository) NoticeTypes(ctx context.Context) (*NoticeTypesResponse, err
 func (r *repository) ClosingSoon(ctx context.Context, limit int, windowSec int64) ([]ClosingSoonItem, error) {
 	now := time.Now().Unix()
 	windowEnd := now + windowSec
+	deadlineRange := bson.M{"$gt": now, "$lte": windowEnd}
 
 	pipeline := mongo.Pipeline{
-		{{Key: "$addFields", Value: bson.M{"effective_deadline": effectiveDeadlineExpr()}}},
 		{{Key: "$match", Value: bson.M{
-			"effective_deadline": bson.M{"$gt": now, "$lte": windowEnd},
+			"$or": bson.A{
+				bson.M{"submission_deadline": deadlineRange},
+				bson.M{
+					"$and": bson.A{
+						bson.M{"$or": bson.A{
+							bson.M{"submission_deadline": bson.M{"$exists": false}},
+							bson.M{"submission_deadline": nil},
+							bson.M{"submission_deadline": bson.M{"$lte": 0}},
+						}},
+						bson.M{"tender_deadline": deadlineRange},
+					},
+				},
+			},
 		}}},
+		{{Key: "$addFields", Value: bson.M{"effective_deadline": effectiveDeadlineExpr()}}},
 		{{Key: "$sort", Value: bson.M{"effective_deadline": 1}}},
 		{{Key: "$limit", Value: limit}},
 		{{Key: "$project", Value: bson.M{

internal/dashboard/service.go

@@ -60,6 +60,11 @@ type service struct {
 	statisticsMu    sync.Mutex
 	statistics      map[int]cacheEntry[*StatisticsReportResponse]
 	statisticsGroup singleflight.Group
+	trendCache      *widgetCache[*TrendResponse]
+	countriesCache  *widgetCache[*CountriesResponse]
+	noticeTypesCache *widgetCache[*NoticeTypesResponse]
+	closingSoonCache *widgetCache[*ClosingSoonResponse]
+	recentCache     *widgetCache[*RecentResponse]
 }
 
 // NewService creates a dashboard service.
@@ -70,9 +75,15 @@ func NewService(repo Repository, log logger.Logger, redisClient redis.Client) Se
 		redis:            redisClient,
 		summary:          make(map[string]cacheEntry[*SummaryResponse]),
 		statistics:       make(map[int]cacheEntry[*StatisticsReportResponse]),
+		trendCache:       newWidgetCache[*TrendResponse](redisClient, log, "trend"),
+		countriesCache:   newWidgetCache[*CountriesResponse](redisClient, log, "countries"),
+		noticeTypesCache: newWidgetCache[*NoticeTypesResponse](redisClient, log, "notice-types"),
+		closingSoonCache: newWidgetCache[*ClosingSoonResponse](redisClient, log, "closing-soon"),
+		recentCache:      newWidgetCache[*RecentResponse](redisClient, log, "recent"),
 	}
 	go s.warmStatisticsCache()
 	go s.warmSummaryCache()
+	go s.warmWidgetCaches()
 	return s
 }
 
@@ -129,6 +140,9 @@ func (s *service) Summary(ctx context.Context, query SummaryQuery) (*SummaryResp
 func (s *service) Trend(ctx context.Context, query TrendQuery) (*TrendResponse, error) {
 	days := trendDays(query.Days)
 	metric := normalizeTrendMetric(query.Metric)
+	cacheKey := fmt.Sprintf("%d:%s", days, metric)
+
+	return s.trendCache.Get(ctx, cacheKey, func(loadCtx context.Context) (*TrendResponse, error) {
 		startUnix := trendStartUnix(days)
 
 		s.logger.Info("Fetching dashboard trend", map[string]interface{}{
@@ -136,7 +150,7 @@ func (s *service) Trend(ctx context.Context, query TrendQuery) (*TrendResponse,
 			"metric": metric,
 		})
 
-	counts, err := s.repo.Trend(ctx, days, metric, startUnix)
+		counts, err := s.repo.Trend(loadCtx, days, metric, startUnix)
 		if err != nil {
 			s.logger.Error("Failed to fetch dashboard trend", map[string]interface{}{
 				"error": err.Error(),
@@ -144,23 +158,24 @@ func (s *service) Trend(ctx context.Context, query TrendQuery) (*TrendResponse,
 			return nil, fmt.Errorf("dashboard trend: %w", err)
 		}
 
-	series := fillTrendSeries(days, counts)
-
 		return &TrendResponse{
 			Metric: metric,
 			Days:   days,
-		Series: series,
+			Series: fillTrendSeries(days, counts),
 		}, nil
+	})
 }
 
 func (s *service) Countries(ctx context.Context, query CountriesQuery) (*CountriesResponse, error) {
 	limit := countriesLimit(query.Limit)
+	cacheKey := strconv.Itoa(limit)
 
+	return s.countriesCache.Get(ctx, cacheKey, func(loadCtx context.Context) (*CountriesResponse, error) {
 		s.logger.Info("Fetching dashboard countries", map[string]interface{}{
 			"limit": limit,
 		})
 
-	out, err := s.repo.Countries(ctx, limit)
+		out, err := s.repo.Countries(loadCtx, limit)
 		if err != nil {
 			s.logger.Error("Failed to fetch dashboard countries", map[string]interface{}{
 				"error": err.Error(),
@@ -169,12 +184,14 @@ func (s *service) Countries(ctx context.Context, query CountriesQuery) (*Countri
 		}
 
 		return out, nil
+	})
 }
 
 func (s *service) NoticeTypes(ctx context.Context) (*NoticeTypesResponse, error) {
+	return s.noticeTypesCache.Get(ctx, "all", func(loadCtx context.Context) (*NoticeTypesResponse, error) {
 		s.logger.Info("Fetching dashboard notice types", nil)
 
-	out, err := s.repo.NoticeTypes(ctx)
+		out, err := s.repo.NoticeTypes(loadCtx)
 		if err != nil {
 			s.logger.Error("Failed to fetch dashboard notice types", map[string]interface{}{
 				"error": err.Error(),
@@ -183,19 +200,22 @@ func (s *service) NoticeTypes(ctx context.Context) (*NoticeTypesResponse, error)
 		}
 
 		return out, nil
+	})
 }
 
 func (s *service) ClosingSoon(ctx context.Context, query ClosingSoonQuery) (*ClosingSoonResponse, error) {
 	limit := listLimit(query.Limit)
 	windowHours := closingWindowHours(query.Window)
 	windowSec := int64(windowHours) * 3600
+	cacheKey := fmt.Sprintf("%d:%d", limit, windowSec)
 
+	return s.closingSoonCache.Get(ctx, cacheKey, func(loadCtx context.Context) (*ClosingSoonResponse, error) {
 		s.logger.Info("Fetching dashboard closing soon", map[string]interface{}{
 			"limit":  limit,
 			"window": windowHours,
 		})
 
-	items, err := s.repo.ClosingSoon(ctx, limit, windowSec)
+		items, err := s.repo.ClosingSoon(loadCtx, limit, windowSec)
 		if err != nil {
 			s.logger.Error("Failed to fetch dashboard closing soon", map[string]interface{}{
 				"error": err.Error(),
@@ -204,16 +224,18 @@ func (s *service) ClosingSoon(ctx context.Context, query ClosingSoonQuery) (*Clo
 		}
 
 		return &ClosingSoonResponse{Items: items}, nil
+	})
 }
 
 func (s *service) Recent(ctx context.Context, query RecentQuery) (*RecentResponse, error) {
 	limit := listLimit(query.Limit)
-
+	cursor := strings.TrimSpace(query.Cursor)
+	if cursor != "" {
 		s.logger.Info("Fetching dashboard recent tenders", map[string]interface{}{
 			"limit": limit,
 		})
 
-	items, nextCursor, err := s.repo.Recent(ctx, limit, strings.TrimSpace(query.Cursor))
+		items, nextCursor, err := s.repo.Recent(ctx, limit, cursor)
 		if err != nil {
 			s.logger.Error("Failed to fetch dashboard recent tenders", map[string]interface{}{
 				"error": err.Error(),
@@ -227,6 +249,27 @@ func (s *service) Recent(ctx context.Context, query RecentQuery) (*RecentRespons
 		}, nil
 	}
 
+	cacheKey := strconv.Itoa(limit)
+	return s.recentCache.Get(ctx, cacheKey, func(loadCtx context.Context) (*RecentResponse, error) {
+		s.logger.Info("Fetching dashboard recent tenders", map[string]interface{}{
+			"limit": limit,
+		})
+
+		items, nextCursor, err := s.repo.Recent(loadCtx, limit, "")
+		if err != nil {
+			s.logger.Error("Failed to fetch dashboard recent tenders", map[string]interface{}{
+				"error": err.Error(),
+			})
+			return nil, fmt.Errorf("dashboard recent: %w", err)
+		}
+
+		return &RecentResponse{
+			Items:      items,
+			NextCursor: nextCursor,
+		}, nil
+	})
+}
+
 func (s *service) Statistics(ctx context.Context, query StatisticsQuery) (*StatisticsReportResponse, error) {
 	days := trendDays(query.Days)
 	if cached, ok := s.cachedStatistics(days); ok {
@@ -339,6 +382,70 @@ func (s *service) loadStatistics(ctx context.Context, days int) (*StatisticsRepo
 	return out.(*StatisticsReportResponse), nil
 }
 
+func (s *service) warmWidgetCaches() {
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	defaultWindowSec := int64(defaultClosingWindowHours) * 3600
+	warmed := 0
+
+	if s.trendCache.WarmFromRedis(ctx, fmt.Sprintf("%d:%s", defaultTrendDays, "created")) {
+		warmed++
+	}
+	if s.countriesCache.WarmFromRedis(ctx, strconv.Itoa(defaultCountriesLimit)) {
+		warmed++
+	}
+	if s.noticeTypesCache.WarmFromRedis(ctx, "all") {
+		warmed++
+	}
+	if s.closingSoonCache.WarmFromRedis(ctx, fmt.Sprintf("%d:%d", defaultListLimit, defaultWindowSec)) {
+		warmed++
+	}
+	if s.recentCache.WarmFromRedis(ctx, strconv.Itoa(defaultListLimit)) {
+		warmed++
+	}
+
+	if warmed > 0 {
+		s.logger.Info("Dashboard widget caches warmed from Redis", map[string]interface{}{
+			"warmed": warmed,
+		})
+	}
+
+	go s.trendCache.Reload(fmt.Sprintf("%d:%s", defaultTrendDays, "created"), func(loadCtx context.Context) (*TrendResponse, error) {
+		return s.loadTrend(loadCtx, TrendQuery{Days: defaultTrendDays, Metric: "created"})
+	})
+	go s.countriesCache.Reload(strconv.Itoa(defaultCountriesLimit), func(loadCtx context.Context) (*CountriesResponse, error) {
+		return s.repo.Countries(loadCtx, defaultCountriesLimit)
+	})
+	go s.noticeTypesCache.Reload("all", func(loadCtx context.Context) (*NoticeTypesResponse, error) {
+		return s.repo.NoticeTypes(loadCtx)
+	})
+	go s.closingSoonCache.Reload(fmt.Sprintf("%d:%d", defaultListLimit, defaultWindowSec), func(loadCtx context.Context) (*ClosingSoonResponse, error) {
+		items, err := s.repo.ClosingSoon(loadCtx, defaultListLimit, defaultWindowSec)
+		if err != nil {
+			return nil, err
+		}
+		return &ClosingSoonResponse{Items: items}, nil
+	})
+}
+
+func (s *service) loadTrend(ctx context.Context, query TrendQuery) (*TrendResponse, error) {
+	days := trendDays(query.Days)
+	metric := normalizeTrendMetric(query.Metric)
+	startUnix := trendStartUnix(days)
+
+	counts, err := s.repo.Trend(ctx, days, metric, startUnix)
+	if err != nil {
+		return nil, err
+	}
+
+	return &TrendResponse{
+		Metric: metric,
+		Days:   days,
+		Series: fillTrendSeries(days, counts),
+	}, nil
+}
+
 func (s *service) warmSummaryCache() {
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 	defer cancel()

internal/dashboard/widget_cache.go

@@ -0,0 +1,224 @@
+package dashboard
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"sync"
+	"time"
+	"tm/pkg/logger"
+	"tm/pkg/redis"
+
+	goredis "github.com/redis/go-redis/v9"
+	"golang.org/x/sync/singleflight"
+)
+
+const (
+	widgetCacheTTL      = 60 * time.Second
+	widgetStaleGraceTTL = 5 * time.Minute
+	widgetReloadTimeout = 2 * time.Minute
+)
+
+type widgetLoader[T any] func(ctx context.Context) (T, error)
+
+type widgetCache[T any] struct {
+	mu         sync.Mutex
+	entries    map[string]cacheEntry[T]
+	group      singleflight.Group
+	redis      redis.Client
+	logger     logger.Logger
+	keyPrefix  string
+	ttl        time.Duration
+	staleGrace time.Duration
+}
+
+func newWidgetCache[T any](redisClient redis.Client, log logger.Logger, keyPrefix string) *widgetCache[T] {
+	return &widgetCache[T]{
+		entries:    make(map[string]cacheEntry[T]),
+		redis:      redisClient,
+		logger:     log,
+		keyPrefix:  keyPrefix,
+		ttl:        widgetCacheTTL,
+		staleGrace: widgetStaleGraceTTL,
+	}
+}
+
+func (c *widgetCache[T]) Get(ctx context.Context, key string, load widgetLoader[T]) (T, error) {
+	var zero T
+
+	if value, ok := c.fresh(key); ok {
+		return value, nil
+	}
+	if value, ok := c.stale(key); ok {
+		go c.Reload(key, load)
+		return value, nil
+	}
+	if value, ok := c.fromRedis(ctx, key); ok {
+		c.store(key, value)
+		go c.Reload(key, load)
+		return value, nil
+	}
+
+	out, err, _ := c.group.Do(key, func() (interface{}, error) {
+		if value, ok := c.fresh(key); ok {
+			return value, nil
+		}
+
+		result, err := load(context.WithoutCancel(ctx))
+		if err != nil {
+			return zero, err
+		}
+
+		c.store(key, result)
+		c.storeRedis(context.Background(), key, result)
+		return result, nil
+	})
+	if err != nil {
+		return zero, err
+	}
+
+	return out.(T), nil
+}
+
+func (c *widgetCache[T]) Reload(key string, load widgetLoader[T]) {
+	ctx, cancel := context.WithTimeout(context.Background(), widgetReloadTimeout)
+	defer cancel()
+
+	_, _, _ = c.group.Do("reload:"+key, func() (interface{}, error) {
+		result, err := load(ctx)
+		if err != nil {
+			if c.logger != nil {
+				c.logger.Warn("Failed to refresh dashboard widget cache", map[string]interface{}{
+					"widget": c.keyPrefix,
+					"key":    key,
+					"error":  err.Error(),
+				})
+			}
+			return nil, err
+		}
+
+		c.store(key, result)
+		c.storeRedis(context.Background(), key, result)
+		return result, nil
+	})
+}
+
+func (c *widgetCache[T]) WarmFromRedis(ctx context.Context, key string) bool {
+	value, ok := c.fromRedis(ctx, key)
+	if !ok {
+		return false
+	}
+	c.store(key, value)
+	return true
+}
+
+func (c *widgetCache[T]) fresh(key string) (T, bool) {
+	var zero T
+	now := time.Now()
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	entry, ok := c.entries[key]
+	if !ok || now.After(entry.expiresAt) {
+		return zero, false
+	}
+
+	return entry.value, true
+}
+
+func (c *widgetCache[T]) stale(key string) (T, bool) {
+	var zero T
+	now := time.Now()
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	entry, ok := c.entries[key]
+	if !ok || now.After(entry.staleUntil) {
+		if ok {
+			delete(c.entries, key)
+		}
+		return zero, false
+	}
+
+	return entry.value, true
+}
+
+func (c *widgetCache[T]) store(key string, value T) {
+	now := time.Now()
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	c.entries[key] = cacheEntry[T]{
+		expiresAt:  now.Add(c.ttl),
+		staleUntil: now.Add(c.ttl + c.staleGrace),
+		value:      value,
+	}
+}
+
+func (c *widgetCache[T]) redisKey(key string) string {
+	return fmt.Sprintf("dashboard:%s:%s", c.keyPrefix, key)
+}
+
+func (c *widgetCache[T]) fromRedis(ctx context.Context, key string) (T, bool) {
+	var zero T
+	if c.redis == nil {
+		return zero, false
+	}
+
+	raw, err := c.redis.Get(ctx, c.redisKey(key))
+	if err != nil {
+		if err != goredis.Nil && c.logger != nil {
+			c.logger.Warn("Failed to read dashboard widget cache from Redis", map[string]interface{}{
+				"widget": c.keyPrefix,
+				"key":    key,
+				"error":  err.Error(),
+			})
+		}
+		return zero, false
+	}
+
+	var value T
+	if err := json.Unmarshal([]byte(raw), &value); err != nil {
+		if c.logger != nil {
+			c.logger.Warn("Failed to decode dashboard widget cache from Redis", map[string]interface{}{
+				"widget": c.keyPrefix,
+				"key":    key,
+				"error":  err.Error(),
+			})
+		}
+		_ = c.redis.Del(ctx, c.redisKey(key))
+		return zero, false
+	}
+
+	return value, true
+}
+
+func (c *widgetCache[T]) storeRedis(ctx context.Context, key string, value T) {
+	if c.redis == nil {
+		return
+	}
+
+	encoded, err := json.Marshal(value)
+	if err != nil {
+		if c.logger != nil {
+			c.logger.Warn("Failed to encode dashboard widget cache for Redis", map[string]interface{}{
+				"widget": c.keyPrefix,
+				"key":    key,
+				"error":  err.Error(),
+			})
+		}
+		return
+	}
+
+	ttl := c.ttl + c.staleGrace
+	if err := c.redis.Set(ctx, c.redisKey(key), string(encoded), ttl); err != nil && c.logger != nil {
+		c.logger.Warn("Failed to store dashboard widget cache in Redis", map[string]interface{}{
+			"widget": c.keyPrefix,
+			"key":    key,
+			"error":  err.Error(),
+		})
+	}
+}

internal/tender/form.go

@@ -70,6 +70,79 @@ type SearchForm struct {
 	ExcludeRejectedTenders bool `query:"-" valid:"optional"`
 }
 
+// HasListFilters reports whether the form applies any MongoDB list filters.
+func (f *SearchForm) HasListFilters() bool {
+	if f == nil {
+		return false
+	}
+	if f.DocumentsScraped || f.OnlyActiveDeadlines || f.ExcludeRejectedTenders {
+		return true
+	}
+	if f.Search != nil && strings.TrimSpace(*f.Search) != "" {
+		return true
+	}
+	if f.Title != nil && strings.TrimSpace(*f.Title) != "" {
+		return true
+	}
+	if f.Description != nil && strings.TrimSpace(*f.Description) != "" {
+		return true
+	}
+	if f.NoticeType != nil && strings.TrimSpace(*f.NoticeType) != "" {
+		return true
+	}
+	if len(f.NoticeTypes) > 0 || len(f.FormTypes) > 0 {
+		return true
+	}
+	if f.ProcurementType != nil && strings.TrimSpace(*f.ProcurementType) != "" {
+		return true
+	}
+	if f.Country != nil && strings.TrimSpace(*f.Country) != "" {
+		return true
+	}
+	if f.CountryCode != nil && strings.TrimSpace(*f.CountryCode) != "" {
+		return true
+	}
+	if len(f.CountryCodes) > 0 || len(f.RegionCodes) > 0 {
+		return true
+	}
+	if f.MainClassification != nil && strings.TrimSpace(*f.MainClassification) != "" {
+		return true
+	}
+	if len(f.Classifications) > 0 || len(f.CpvCodes) > 0 {
+		return true
+	}
+	if f.MinEstimatedValue != nil || f.MaxEstimatedValue != nil || f.Currency != "" {
+		return true
+	}
+	if f.CreatedAt != nil || f.CreatedAtFrom != nil || f.CreatedAtTo != nil {
+		return true
+	}
+	if f.TenderDeadline != nil || f.TenderDeadlineFrom != nil || f.TenderDeadlineTo != nil ||
+		f.DeadlineFrom != nil || f.DeadlineTo != nil {
+		return true
+	}
+	if f.PublicationDate != nil || f.PublicationDateFrom != nil || f.PublicationDateTo != nil {
+		return true
+	}
+	if f.SubmissionDeadline != nil || f.SubmissionDateAliasFrom != nil || f.SubmissionDateAliasTo != nil ||
+		f.SubmissionDateFrom != nil || f.SubmissionDateTo != nil {
+		return true
+	}
+	if len(f.Status) > 0 || len(f.Source) > 0 || len(f.Languages) > 0 {
+		return true
+	}
+	if f.BuyerOrganizationID != nil && strings.TrimSpace(*f.BuyerOrganizationID) != "" {
+		return true
+	}
+	if f.NoticePublicationID != nil && strings.TrimSpace(*f.NoticePublicationID) != "" {
+		return true
+	}
+	if len(f.ContractFolderIDsWithDocuments) > 0 {
+		return true
+	}
+	return false
+}
+
 // SearchResponse represents the response for listing tenders
 type SearchResponse struct {
 	Tenders  []TenderResponse `json:"tenders"`

internal/tender/repository.go

@@ -130,6 +130,15 @@ func NewRepository(mongoManager *orm.ConnectionManager, logger logger.Logger) Te
 		*orm.NewIndex("main_classification_idx", bson.D{{Key: "main_classification", Value: 1}}),
 		*orm.NewIndex("publication_date_idx", bson.D{{Key: "publication_date", Value: -1}}),
 		*orm.NewIndex("tender_deadline_idx", bson.D{{Key: "tender_deadline", Value: 1}}),
+		*orm.NewIndex("submission_deadline_idx", bson.D{{Key: "submission_deadline", Value: 1}}),
+		*orm.NewIndex("closing_soon_submission_idx", bson.D{
+			{Key: "submission_deadline", Value: 1},
+			{Key: "status", Value: 1},
+		}),
+		*orm.NewIndex("closing_soon_tender_deadline_idx", bson.D{
+			{Key: "tender_deadline", Value: 1},
+			{Key: "status", Value: 1},
+		}),
 		*orm.NewIndex("estimated_value_idx", bson.D{{Key: "estimated_value", Value: -1}}),
 		*orm.NewIndex("created_at_idx", bson.D{{Key: "created_at", Value: -1}}),
 		// Stable keyset pagination for default admin list (created_at desc).

internal/tender/search_list_cache.go

@@ -0,0 +1,236 @@
+package tender
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"time"
+
+	goredis "github.com/redis/go-redis/v9"
+	"tm/pkg/response"
+)
+
+const (
+	searchListCacheTTL       = 60 * time.Second
+	searchListCacheStaleTTL  = 5 * time.Minute
+	searchListCacheKeyPrefix = "tender:search:list:"
+)
+
+type searchListCacheEntry struct {
+	expiresAt  time.Time
+	staleUntil time.Time
+	value      *SearchResponse
+}
+
+type cachedSearchListPayload struct {
+	Tenders  []TenderResponse `json:"tenders"`
+	Metadata *response.Meta   `json:"metadata,omitempty"`
+}
+
+func searchResponseToCachePayload(resp *SearchResponse) *cachedSearchListPayload {
+	if resp == nil {
+		return nil
+	}
+	return &cachedSearchListPayload{
+		Tenders:  resp.Tenders,
+		Metadata: resp.Metadata,
+	}
+}
+
+func cachePayloadToSearchResponse(payload *cachedSearchListPayload) *SearchResponse {
+	if payload == nil {
+		return nil
+	}
+	return &SearchResponse{
+		Tenders:  payload.Tenders,
+		Metadata: payload.Metadata,
+	}
+}
+
+func isCacheableSearchList(form *SearchForm, pagination *response.Pagination) bool {
+	if form == nil || pagination == nil {
+		return false
+	}
+	if form.HasListFilters() {
+		return false
+	}
+	if form.CompanyID != nil && strings.TrimSpace(*form.CompanyID) != "" {
+		return false
+	}
+	if form.CustomerID != nil && strings.TrimSpace(*form.CustomerID) != "" {
+		return false
+	}
+	if len(form.CompanyIDs) > 0 {
+		return false
+	}
+	if pagination.Cursor != "" || pagination.IncludeTotal || pagination.Offset != 0 {
+		return false
+	}
+	if pagination.Limit <= 0 || pagination.Limit > 20 {
+		return false
+	}
+
+	sortBy := pagination.SortBy
+	if sortBy == "" {
+		sortBy = "created_at"
+	}
+	sortOrder := pagination.SortOrder
+	if sortOrder == "" {
+		sortOrder = "desc"
+	}
+
+	return sortBy == "created_at" && sortOrder == "desc"
+}
+
+func searchListCacheKey(pagination *response.Pagination, language string) string {
+	return fmt.Sprintf("%d:%s", pagination.Limit, strings.ToLower(strings.TrimSpace(language)))
+}
+
+func (s *tenderService) cachedSearchList(ctx context.Context, form *SearchForm, pagination *response.Pagination, language string, load func(context.Context) (*SearchResponse, error)) (*SearchResponse, error) {
+	if !isCacheableSearchList(form, pagination) {
+		return load(ctx)
+	}
+
+	cacheKey := searchListCacheKey(pagination, language)
+	redisKey := searchListCacheKeyPrefix + cacheKey
+
+	if cached, ok := s.getFreshSearchListCache(cacheKey); ok {
+		return cached, nil
+	}
+	if stale, ok := s.getStaleSearchListCache(cacheKey); ok {
+		go s.refreshSearchListCache(cacheKey, redisKey, load)
+		return stale, nil
+	}
+	if cached, ok := s.getRedisSearchListCache(ctx, redisKey); ok {
+		s.storeSearchListCache(cacheKey, cached)
+		go s.refreshSearchListCache(cacheKey, redisKey, load)
+		return cached, nil
+	}
+
+	out, err, _ := s.searchListCacheGroup.Do(cacheKey, func() (interface{}, error) {
+		if cached, ok := s.getFreshSearchListCache(cacheKey); ok {
+			return cached, nil
+		}
+
+		result, err := load(context.WithoutCancel(ctx))
+		if err != nil {
+			return nil, err
+		}
+
+		s.storeSearchListCache(cacheKey, result)
+		s.storeRedisSearchListCache(context.Background(), redisKey, result)
+		return result, nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return out.(*SearchResponse), nil
+}
+
+func (s *tenderService) refreshSearchListCache(cacheKey, redisKey string, load func(context.Context) (*SearchResponse, error)) {
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Minute)
+	defer cancel()
+
+	result, err := load(ctx)
+	if err != nil {
+		s.logger.Warn("Failed to refresh tender search list cache", map[string]interface{}{
+			"cache_key": cacheKey,
+			"error":     err.Error(),
+		})
+		return
+	}
+
+	s.storeSearchListCache(cacheKey, result)
+	s.storeRedisSearchListCache(context.Background(), redisKey, result)
+}
+
+func (s *tenderService) getFreshSearchListCache(cacheKey string) (*SearchResponse, bool) {
+	s.searchListCacheMu.Lock()
+	defer s.searchListCacheMu.Unlock()
+
+	entry, ok := s.searchListCache[cacheKey]
+	if !ok || time.Now().After(entry.expiresAt) {
+		return nil, false
+	}
+	return entry.value, true
+}
+
+func (s *tenderService) getStaleSearchListCache(cacheKey string) (*SearchResponse, bool) {
+	s.searchListCacheMu.Lock()
+	defer s.searchListCacheMu.Unlock()
+
+	entry, ok := s.searchListCache[cacheKey]
+	if !ok || time.Now().After(entry.staleUntil) {
+		if ok {
+			delete(s.searchListCache, cacheKey)
+		}
+		return nil, false
+	}
+	return entry.value, true
+}
+
+func (s *tenderService) storeSearchListCache(cacheKey string, value *SearchResponse) {
+	now := time.Now()
+
+	s.searchListCacheMu.Lock()
+	defer s.searchListCacheMu.Unlock()
+
+	s.searchListCache[cacheKey] = searchListCacheEntry{
+		expiresAt:  now.Add(searchListCacheTTL),
+		staleUntil: now.Add(searchListCacheTTL + searchListCacheStaleTTL),
+		value:      value,
+	}
+}
+
+func (s *tenderService) getRedisSearchListCache(ctx context.Context, redisKey string) (*SearchResponse, bool) {
+	if s.redisClient == nil {
+		return nil, false
+	}
+
+	raw, err := s.redisClient.Get(ctx, redisKey)
+	if err != nil {
+		if err != goredis.Nil {
+			s.logger.Warn("Failed to read tender search list cache from Redis", map[string]interface{}{
+				"cache_key": redisKey,
+				"error":     err.Error(),
+			})
+		}
+		return nil, false
+	}
+
+	var cached cachedSearchListPayload
+	if err := json.Unmarshal([]byte(raw), &cached); err != nil {
+		s.logger.Warn("Failed to decode tender search list cache from Redis", map[string]interface{}{
+			"cache_key": redisKey,
+			"error":     err.Error(),
+		})
+		_ = s.redisClient.Del(ctx, redisKey)
+		return nil, false
+	}
+
+	return cachePayloadToSearchResponse(&cached), true
+}
+
+func (s *tenderService) storeRedisSearchListCache(ctx context.Context, redisKey string, value *SearchResponse) {
+	if s.redisClient == nil || value == nil {
+		return
+	}
+
+	encoded, err := json.Marshal(searchResponseToCachePayload(value))
+	if err != nil {
+		s.logger.Warn("Failed to encode tender search list cache for Redis", map[string]interface{}{
+			"cache_key": redisKey,
+			"error":     err.Error(),
+		})
+		return
+	}
+
+	if err := s.redisClient.Set(ctx, redisKey, string(encoded), searchListCacheTTL+searchListCacheStaleTTL); err != nil {
+		s.logger.Warn("Failed to store tender search list cache in Redis", map[string]interface{}{
+			"cache_key": redisKey,
+			"error":     err.Error(),
+		})
+	}
+}

internal/tender/service.go

@@ -10,6 +10,7 @@ import (
 	"path"
 	"path/filepath"
 	"strings"
+	"sync"
 	"time"
 	"tm/internal/company"
 	"tm/internal/customer"
@@ -20,6 +21,7 @@ import (
 	"tm/pkg/response"
 
 	"golang.org/x/sync/errgroup"
+	"golang.org/x/sync/singleflight"
 )
 
 // AISummarizerClient defines the interface for on-demand AI operations.
@@ -95,6 +97,9 @@ type tenderService struct {
 	redisClient          redis.Client
 	pageCacheTTL         time.Duration
 	defaultLanguage      string
+	searchListCacheMu    sync.Mutex
+	searchListCache      map[string]searchListCacheEntry
+	searchListCacheGroup singleflight.Group
 }
 
 const (
@@ -136,6 +141,7 @@ func NewService(
 		redisClient:          redisClient,
 		pageCacheTTL:         recommendationPageCacheTTL,
 		defaultLanguage:      strings.ToLower(defaultLanguage),
+		searchListCache:      make(map[string]searchListCacheEntry),
 	}
 }
 
@@ -922,8 +928,13 @@ func (s *tenderService) Search(ctx context.Context, form *SearchForm, pagination
 		"to":          form.DeadlineTo,
 	})
 
-	// Profile keywords are not used for tender search.
+	language := s.pickResponseLanguage(form.Language)
+	return s.cachedSearchList(ctx, form, pagination, language, func(loadCtx context.Context) (*SearchResponse, error) {
+		return s.searchUncached(loadCtx, form, pagination, language)
+	})
+}
 
+func (s *tenderService) searchUncached(ctx context.Context, form *SearchForm, pagination *response.Pagination, language string) (*SearchResponse, error) {
 	page, err := s.repository.Search(ctx, form, pagination)
 	if err != nil {
 		s.logger.Error("Failed to list tenders", map[string]interface{}{
@@ -936,7 +947,7 @@ func (s *tenderService) Search(ctx context.Context, form *SearchForm, pagination
 	if form.CompanyID == nil || *form.CompanyID == "" {
 		tenderResponses := make([]TenderResponse, 0, len(page.Items))
 		for _, tender := range page.Items {
-			tenderResponses = append(tenderResponses, *tender.ToResponseWithLanguage(s.pickResponseLanguage(form.Language)))
+			tenderResponses = append(tenderResponses, *tender.ToResponseWithLanguage(language))
 		}
 
 		return &SearchResponse{
@@ -955,7 +966,7 @@ func (s *tenderService) Search(ctx context.Context, form *SearchForm, pagination
 		// Continue without match percentage if company not found
 		tenderResponses := make([]TenderResponse, 0, len(page.Items))
 		for _, tender := range page.Items {
-			tenderResponses = append(tenderResponses, *tender.ToResponseWithLanguage(s.pickResponseLanguage(form.Language)))
+			tenderResponses = append(tenderResponses, *tender.ToResponseWithLanguage(language))
 		}
 
 		return &SearchResponse{
@@ -978,7 +989,7 @@ func (s *tenderService) Search(ctx context.Context, form *SearchForm, pagination
 
 	tenderResponses := make([]TenderResponse, 0, len(page.Items))
 	for _, tender := range page.Items {
-		tenderResponses = append(tenderResponses, *tender.ToResponseWithLanguage(s.pickResponseLanguage(form.Language)))
+		tenderResponses = append(tenderResponses, *tender.ToResponseWithLanguage(language))
 	}
 
 	return &SearchResponse{