Enhance tender recommendation caching and page refresh logic

- Introduced a new `RecommendedTendersPageCacheRefresher` interface to manage the asynchronous refresh of recommendation pages in Redis, improving cache management.
- Updated the `companyService` to support setting page cache languages and refreshing the recommended tenders page cache based on company IDs.
- Enhanced the `tenderService` to build and invalidate recommended tenders page caches, ensuring timely updates and efficient retrieval of cached recommendations.
- Added configuration options for recommendation page cache languages in the `AISummarizerConfig`, allowing for flexible language support.
- Implemented unit tests for the new caching logic and page refresh functionality, ensuring robust validation of the recommendation caching process.

This update significantly improves the efficiency and responsiveness of the tender recommendation service by integrating enhanced caching mechanisms and page refresh capabilities.

internal/company/page_cache_refresher.go

@@ -0,0 +1,7 @@
+package company
+
+// RecommendedTendersPageCacheRefresher pre-builds resolved recommendation pages in Redis.
+// Implemented by the tender service on the web API; optional on the worker.
+type RecommendedTendersPageCacheRefresher interface {
+	ScheduleRefreshRecommendedTendersPageCache(companyID string)
+}

internal/company/recommendation.go

@@ -464,7 +464,11 @@ func (s *companyService) cacheAIRecommendations(ctx context.Context, companyID s
 			"company_id": companyID,
 			"error":      err.Error(),
 		})
+		return
 	}
+
+	s.invalidateRecommendedTendersPageCache(ctx, companyID)
+	s.scheduleRecommendedTendersPageCacheRefresh(companyID)
 }
 
 func (s *companyService) recommendationCacheExpiration() time.Duration {
@@ -485,6 +489,7 @@ func (s *companyService) invalidateAIRecommendationCache(ctx context.Context, co
 			"error":      err.Error(),
 		})
 	}
+	s.invalidateRecommendedTendersPageCache(ctx, companyID)
 }
 
 func (s *companyService) buildOnboardingDocuments(fileIDs []string) (string, error) {

internal/company/recommendation_page_cache.go

@@ -0,0 +1,71 @@
+package company
+
+import (
+	"context"
+	"strings"
+)
+
+const recommendedTendersPageCacheKeyPrefix = "ai:recommendations:page:"
+
+func recommendedTendersPageCacheKey(companyID, language string) string {
+	return recommendedTendersPageCacheKeyPrefix +
+		strings.TrimSpace(companyID) + ":" +
+		strings.ToLower(strings.TrimSpace(language))
+}
+
+func (s *companyService) invalidateRecommendedTendersPageCache(ctx context.Context, companyID string) {
+	if s.redisClient == nil {
+		return
+	}
+
+	for _, language := range s.pageCacheLanguages {
+		lang := strings.ToLower(strings.TrimSpace(language))
+		if lang == "" {
+			continue
+		}
+		_ = s.redisClient.Del(ctx, recommendedTendersPageCacheKey(companyID, lang))
+	}
+}
+
+func (s *companyService) scheduleRecommendedTendersPageCacheRefresh(companyID string) {
+	if s.pageCacheRefresher == nil {
+		return
+	}
+	s.pageCacheRefresher.ScheduleRefreshRecommendedTendersPageCache(companyID)
+}
+
+// SetRecommendedTendersPageCacheRefresher wires async page-cache rebuilds from the tender service.
+func (s *companyService) SetRecommendedTendersPageCacheRefresher(refresher RecommendedTendersPageCacheRefresher) {
+	s.pageCacheRefresher = refresher
+}
+
+// SetPageCacheLanguages configures which language variants are invalidated in Redis.
+func (s *companyService) SetPageCacheLanguages(languages []string) {
+	s.pageCacheLanguages = normalizePageCacheLanguages("", languages)
+}
+
+func normalizePageCacheLanguages(defaultLanguage string, languages []string) []string {
+	seen := make(map[string]struct{})
+	out := make([]string, 0, len(languages)+1)
+
+	add := func(lang string) {
+		lang = strings.ToLower(strings.TrimSpace(lang))
+		if lang == "" {
+			return
+		}
+		if _, ok := seen[lang]; ok {
+			return
+		}
+		seen[lang] = struct{}{}
+		out = append(out, lang)
+	}
+
+	add(defaultLanguage)
+	for _, lang := range languages {
+		add(lang)
+	}
+	if len(out) == 0 {
+		out = append(out, "en")
+	}
+	return out
+}

internal/company/service.go

@@ -60,8 +60,10 @@ type companyService struct {
 	fileStore              filestore.FileStoreService
 	aiRecommendationClient AIRecommendationClient
 	aiPipelineStatusClient AIPipelineStatusClient
+	pageCacheRefresher     RecommendedTendersPageCacheRefresher
 	redisClient            redis.Client
 	recommendationCacheTTL time.Duration
+	pageCacheLanguages     []string
 	logger                 logger.Logger
 }
 

internal/tender/recommendation_page_cache.go

@@ -0,0 +1,423 @@
+package tender
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+	"go.mongodb.org/mongo-driver/v2/bson"
+	"golang.org/x/sync/errgroup"
+
+	"tm/internal/company"
+	"tm/pkg/response"
+)
+
+const (
+	recommendedTendersPageCacheKeyPrefix = "ai:recommendations:page:"
+	recommendationPageCacheReadTimeout   = 3 * time.Second
+	recommendationPageCacheBuildTimeout  = 5 * time.Minute
+	recommendationPageCacheConcurrency   = 8
+)
+
+type cachedRecommendedTendersPage struct {
+	BuiltAt   int64            `json:"built_at"`
+	CompanyID string           `json:"company_id"`
+	Language  string           `json:"language"`
+	Items     []TenderResponse `json:"items"`
+}
+
+func recommendedTendersPageCacheKey(companyID, language string) string {
+	return recommendedTendersPageCacheKeyPrefix +
+		strings.TrimSpace(companyID) + ":" +
+		strings.ToLower(strings.TrimSpace(language))
+}
+
+// ScheduleRefreshRecommendedTendersPageCache rebuilds resolved recommendation pages asynchronously.
+func (s *tenderService) ScheduleRefreshRecommendedTendersPageCache(companyID string) {
+	companyID = strings.TrimSpace(companyID)
+	if companyID == "" || s.redisClient == nil {
+		return
+	}
+
+	go func() {
+		ctx, cancel := context.WithTimeout(context.Background(), recommendationPageCacheBuildTimeout)
+		defer cancel()
+
+		for _, language := range s.pageCacheLanguages {
+			lang := strings.ToLower(strings.TrimSpace(language))
+			if lang == "" {
+				continue
+			}
+			if err := s.buildRecommendedTendersPageCache(ctx, companyID, lang); err != nil {
+				s.logger.Warn("Failed to refresh recommended tenders page cache", map[string]interface{}{
+					"company_id": companyID,
+					"language":   lang,
+					"error":      err.Error(),
+				})
+			}
+		}
+	}()
+}
+
+func (s *tenderService) buildRecommendedTendersPageCache(ctx context.Context, companyID, language string) error {
+	recommendations, err := s.companyService.GetAIRecommendations(ctx, companyID)
+	if err != nil {
+		return err
+	}
+	if len(recommendations) == 0 {
+		s.deleteRecommendedTendersPageCache(ctx, companyID, language)
+		return nil
+	}
+
+	items, err := s.buildAllRankedRecommendations(ctx, recommendations)
+	if err != nil {
+		return err
+	}
+	if len(items) == 0 {
+		s.deleteRecommendedTendersPageCache(ctx, companyID, language)
+		return nil
+	}
+
+	responses := s.buildRecommendedTenderResponsesParallel(ctx, items, language)
+	page := cachedRecommendedTendersPage{
+		BuiltAt:   time.Now().Unix(),
+		CompanyID: companyID,
+		Language:  language,
+		Items:     responses,
+	}
+
+	encoded, err := json.Marshal(page)
+	if err != nil {
+		return fmt.Errorf("encode recommended tenders page cache: %w", err)
+	}
+
+	writeCtx, cancel := context.WithTimeout(ctx, recommendationPageCacheReadTimeout)
+	defer cancel()
+
+	if err := s.redisClient.Set(writeCtx, recommendedTendersPageCacheKey(companyID, language), string(encoded), s.pageCacheTTL); err != nil {
+		return fmt.Errorf("store recommended tenders page cache: %w", err)
+	}
+
+	s.logger.Info("Recommended tenders page cache built", map[string]interface{}{
+		"company_id": companyID,
+		"language":   language,
+		"count":      len(responses),
+	})
+	return nil
+}
+
+func (s *tenderService) getRecommendedTendersPageCache(ctx context.Context, companyID, language string) ([]TenderResponse, bool) {
+	if s.redisClient == nil {
+		return nil, false
+	}
+
+	readCtx, cancel := context.WithTimeout(ctx, recommendationPageCacheReadTimeout)
+	defer cancel()
+
+	raw, err := s.redisClient.Get(readCtx, recommendedTendersPageCacheKey(companyID, language))
+	if err != nil {
+		if err != redis.Nil {
+			s.logger.Warn("Failed to read recommended tenders page cache", map[string]interface{}{
+				"company_id": companyID,
+				"language":   language,
+				"error":      err.Error(),
+			})
+		}
+		return nil, false
+	}
+
+	var page cachedRecommendedTendersPage
+	if err := json.Unmarshal([]byte(raw), &page); err != nil {
+		s.logger.Warn("Failed to decode recommended tenders page cache", map[string]interface{}{
+			"company_id": companyID,
+			"language":   language,
+			"error":      err.Error(),
+		})
+		s.deleteRecommendedTendersPageCache(ctx, companyID, language)
+		return nil, false
+	}
+	if len(page.Items) == 0 {
+		return nil, false
+	}
+
+	return page.Items, true
+}
+
+func (s *tenderService) deleteRecommendedTendersPageCache(ctx context.Context, companyID, language string) {
+	if s.redisClient == nil {
+		return
+	}
+	_ = s.redisClient.Del(ctx, recommendedTendersPageCacheKey(companyID, language))
+}
+
+func (s *tenderService) buildAllRankedRecommendations(
+	ctx context.Context,
+	recommendations []company.RecommendedTenderResponse,
+) ([]rankedRecommendedTender, error) {
+	seenTenderIDs := make(map[string]struct{}, len(recommendations))
+	out := make([]rankedRecommendedTender, 0, len(recommendations))
+
+	for start := 0; start < len(recommendations); start += recommendationResolveBatchSize {
+		end := start + recommendationResolveBatchSize
+		if end > len(recommendations) {
+			end = len(recommendations)
+		}
+
+		tenderByRef, err := s.resolveRecommendedTenders(ctx, recommendations[start:end])
+		if err != nil {
+			return nil, err
+		}
+
+		for _, rec := range recommendations[start:end] {
+			tenderRef := strings.TrimSpace(rec.TenderID)
+			tender, ok := tenderByRef[tenderRef]
+			if !ok {
+				continue
+			}
+			if markResolvedRecommendedTenderSeen(seenTenderIDs, tender, tenderRef) {
+				continue
+			}
+
+			out = append(out, rankedRecommendedTender{
+				tender:    tender,
+				rank:      rec.Rank,
+				analysis:  rec.Analysis,
+				tenderRef: tenderRef,
+			})
+		}
+	}
+
+	return out, nil
+}
+
+func (s *tenderService) buildRecommendedTenderResponsesParallel(
+	ctx context.Context,
+	items []rankedRecommendedTender,
+	language string,
+) []TenderResponse {
+	if len(items) == 0 {
+		return nil
+	}
+
+	out := make([]TenderResponse, len(items))
+	if len(items) == 1 {
+		out[0] = s.buildRecommendedTenderResponse(
+			ctx, items[0].tender, items[0].rank, items[0].analysis, items[0].tenderRef, language,
+			newRecommendationTranslationCache(),
+		)
+		return out
+	}
+
+	translationCache := newRecommendationTranslationCache()
+	group, groupCtx := errgroup.WithContext(ctx)
+	group.SetLimit(recommendationPageCacheConcurrency)
+
+	for i := range items {
+		i := i
+		item := items[i]
+		group.Go(func() error {
+			out[i] = s.buildRecommendedTenderResponse(
+				groupCtx, item.tender, item.rank, item.analysis, item.tenderRef, language, translationCache,
+			)
+			return nil
+		})
+	}
+
+	if err := group.Wait(); err != nil {
+		s.logger.Warn("Parallel recommendation page cache build degraded to sequential", map[string]interface{}{
+			"error": err.Error(),
+			"count": len(items),
+		})
+		for i, item := range items {
+			out[i] = s.buildRecommendedTenderResponse(
+				ctx, item.tender, item.rank, item.analysis, item.tenderRef, language, translationCache,
+			)
+		}
+	}
+
+	return out
+}
+
+func (s *tenderService) recommendFromPageCache(
+	ctx context.Context,
+	companyID string,
+	companyIDs []string,
+	form *SearchForm,
+	pagination *response.Pagination,
+	lang string,
+) (*SearchResponse, bool) {
+	var cached []TenderResponse
+	if len(companyIDs) > 0 {
+		cached = s.mergeCachedRecommendationPages(ctx, companyIDs, lang)
+	} else {
+		items, ok := s.getRecommendedTendersPageCache(ctx, companyID, lang)
+		if !ok {
+			return nil, false
+		}
+		cached = items
+	}
+	if len(cached) == 0 {
+		return nil, false
+	}
+
+	excluded, excludedByCompany, err := s.loadRecommendationExclusions(ctx, form, companyID, companyIDs)
+	if err != nil {
+		return nil, false
+	}
+
+	now := time.Now().Unix()
+	filtered := filterCachedRecommendedTenders(cached, form, companyIDs, excluded, excludedByCompany, now)
+	total := int64(len(filtered))
+
+	start := pagination.Offset
+	if start > len(filtered) {
+		start = len(filtered)
+	}
+	end := start + pagination.Limit
+	if end > len(filtered) {
+		end = len(filtered)
+	}
+
+	return &SearchResponse{
+		Tenders:  append([]TenderResponse(nil), filtered[start:end]...),
+		Metadata: pagination.ListMeta(total, "", end < len(filtered), start),
+	}, true
+}
+
+func (s *tenderService) mergeCachedRecommendationPages(ctx context.Context, companyIDs []string, lang string) []TenderResponse {
+	normalized := normalizeRecommendationCompanyScope(companyIDs)
+	if len(normalized) == 0 {
+		return nil
+	}
+
+	lists := make([][]TenderResponse, 0, len(normalized))
+	for _, companyID := range normalized {
+		items, ok := s.getRecommendedTendersPageCache(ctx, companyID, lang)
+		if !ok || len(items) == 0 {
+			return nil
+		}
+		lists = append(lists, items)
+	}
+
+	merged := make([]TenderResponse, 0)
+	for _, list := range lists {
+		merged = append(merged, list...)
+	}
+	return dedupeCachedRecommendedTendersByID(merged)
+}
+
+func dedupeCachedRecommendedTendersByID(items []TenderResponse) []TenderResponse {
+	seen := make(map[string]struct{}, len(items))
+	out := make([]TenderResponse, 0, len(items))
+	for _, item := range items {
+		key := strings.TrimSpace(item.ID)
+		if key == "" {
+			key = strings.TrimSpace(item.ProcedureRef)
+		}
+		if key == "" {
+			continue
+		}
+		if _, exists := seen[key]; exists {
+			continue
+		}
+		seen[key] = struct{}{}
+		out = append(out, item)
+	}
+	return out
+}
+
+func filterCachedRecommendedTenders(
+	items []TenderResponse,
+	form *SearchForm,
+	companyIDs []string,
+	excluded map[string]struct{},
+	excludedByCompany map[string]map[string]struct{},
+	now int64,
+) []TenderResponse {
+	if len(items) == 0 {
+		return nil
+	}
+
+	out := make([]TenderResponse, 0, len(items))
+	for _, item := range items {
+		tender := tenderFromRecommendationResponse(item)
+		tenderRef := strings.TrimSpace(item.ProcedureRef)
+
+		if len(companyIDs) > 0 {
+			if isRecommendedTenderExcludedForAllCompanies(tender, tenderRef, excludedByCompany, companyIDs) {
+				continue
+			}
+		} else if isRecommendedTenderExcluded(tender, tenderRef, excluded) {
+			continue
+		}
+		if form.OnlyActiveDeadlines && !tender.IsRecommendable(now) {
+			continue
+		}
+		if len(form.Status) > 0 && !statusAllowed(tender.Status, form.Status) {
+			continue
+		}
+
+		out = append(out, item)
+	}
+	return out
+}
+
+func tenderFromRecommendationResponse(item TenderResponse) Tender {
+	var tender Tender
+	if id, err := bson.ObjectIDFromHex(strings.TrimSpace(item.ID)); err == nil {
+		tender.ID = id
+	}
+	tender.ContractFolderID = item.ContractFolderID
+	tender.NoticePublicationID = item.NoticePublicationID
+	tender.RelatedNoticePublicationIDs = append([]string(nil), item.RelatedNoticePublicationIDs...)
+	tender.Status = item.Status
+	tender.PublicationDate = item.PublicationDate
+	tender.SubmissionDeadline = item.SubmissionDeadline
+	tender.TenderDeadline = item.TenderDeadline
+	return tender
+}
+
+func normalizePageCacheLanguages(defaultLanguage string, languages []string) []string {
+	seen := make(map[string]struct{})
+	out := make([]string, 0, len(languages)+1)
+
+	add := func(lang string) {
+		lang = strings.ToLower(strings.TrimSpace(lang))
+		if lang == "" {
+			return
+		}
+		if _, ok := seen[lang]; ok {
+			return
+		}
+		seen[lang] = struct{}{}
+		out = append(out, lang)
+	}
+
+	add(defaultLanguage)
+	for _, lang := range languages {
+		add(lang)
+	}
+	if len(out) == 0 {
+		out = append(out, "en")
+	}
+	return out
+}
+
+// ParsePageCacheLanguagesConfig splits a comma-separated language list for cache prewarm.
+func ParsePageCacheLanguagesConfig(raw string) []string {
+	if strings.TrimSpace(raw) == "" {
+		return normalizePageCacheLanguages("en", nil)
+	}
+	return normalizePageCacheLanguages("", strings.Split(raw, ","))
+}
+
+// RecommendedTendersPageCacheKeyPrefix is shared with company invalidation logic.
+const RecommendedTendersPageCacheKeyPrefix = recommendedTendersPageCacheKeyPrefix
+
+// RecommendedTendersPageCacheKey builds the Redis key for a cached recommendation page.
+func RecommendedTendersPageCacheKey(companyID, language string) string {
+	return recommendedTendersPageCacheKey(companyID, language)
+}

internal/tender/recommendation_page_cache_test.go

@@ -0,0 +1,54 @@
+package tender
+
+import (
+	"testing"
+
+	"go.mongodb.org/mongo-driver/v2/bson"
+)
+
+func TestFilterCachedRecommendedTendersAppliesActiveAndRejectedFilters(t *testing.T) {
+	activeID, _ := bson.ObjectIDFromHex("507f1f77bcf86cd799439011")
+	expiredID, _ := bson.ObjectIDFromHex("507f1f77bcf86cd799439012")
+
+	items := []TenderResponse{
+		{
+			ID:                 activeID.Hex(),
+			Status:             TenderStatusActive,
+			PublicationDate:    1,
+			SubmissionDeadline: 9999999999,
+			ProcedureRef:       "PROC_folder-a/notice-a",
+			Rank:               1,
+		},
+		{
+			ID:              expiredID.Hex(),
+			Status:          TenderStatusExpired,
+			ProcedureRef:    "PROC_folder-b/notice-b",
+			Rank:            2,
+		},
+	}
+
+	form := &SearchForm{
+		OnlyActiveDeadlines:    true,
+		ExcludeRejectedTenders: true,
+		Status:                 []string{string(TenderStatusActive)},
+	}
+	excluded := map[string]struct{}{expiredID.Hex(): {}}
+
+	got := filterCachedRecommendedTenders(items, form, nil, excluded, nil, 100)
+	if len(got) != 1 {
+		t.Fatalf("len = %d, want 1", len(got))
+	}
+	if got[0].ID != activeID.Hex() {
+		t.Fatalf("got ID %q, want active tender", got[0].ID)
+	}
+}
+
+func TestParsePageCacheLanguagesConfig(t *testing.T) {
+	got := ParsePageCacheLanguagesConfig("en,fr, en")
+	if len(got) != 2 {
+		t.Fatalf("len = %d, want 2", len(got))
+	}
+	if got[0] != "en" || got[1] != "fr" {
+		t.Fatalf("got %v, want [en fr]", got)
+	}
+}

internal/tender/service.go

@@ -16,6 +16,7 @@ import (
 	"tm/pkg/ai_summarizer"
 	"tm/pkg/logger"
 	orm "tm/pkg/mongo"
+	"tm/pkg/redis"
 	"tm/pkg/response"
 
 	"golang.org/x/sync/errgroup"
@@ -89,6 +90,9 @@ type tenderService struct {
 	logger               logger.Logger
 	aiSummarizerClient   AISummarizerClient
 	aiSummarizerStorage  AISummarizerStorage
+	redisClient          redis.Client
+	pageCacheTTL         time.Duration
+	pageCacheLanguages   []string
 	defaultLanguage      string
 }
 
@@ -111,6 +115,9 @@ func NewService(
 	logger logger.Logger,
 	aiClient AISummarizerClient,
 	aiStorage AISummarizerStorage,
+	redisClient redis.Client,
+	recommendationPageCacheTTL time.Duration,
+	recommendationPageCacheLanguages []string,
 	defaultLanguage string,
 ) Service {
 	if strings.TrimSpace(defaultLanguage) == "" {
@@ -125,6 +132,9 @@ func NewService(
 		logger:               logger,
 		aiSummarizerClient:   aiClient,
 		aiSummarizerStorage:  aiStorage,
+		redisClient:          redisClient,
+		pageCacheTTL:         recommendationPageCacheTTL,
+		pageCacheLanguages:   normalizePageCacheLanguages(defaultLanguage, recommendationPageCacheLanguages),
 		defaultLanguage:      strings.ToLower(defaultLanguage),
 	}
 }
@@ -967,6 +977,11 @@ func (s *tenderService) Recommend(ctx context.Context, form *SearchForm, paginat
 		"company_ids": companyIDs,
 	})
 
+	lang := s.pickResponseLanguage(form.Language)
+	if result, ok := s.recommendFromPageCache(ctx, companyID, companyIDs, form, pagination, lang); ok {
+		return result, nil
+	}
+
 	var (
 		recommendations []company.RecommendedTenderResponse
 		err             error
@@ -983,6 +998,10 @@ func (s *tenderService) Recommend(ctx context.Context, form *SearchForm, paginat
 		return s.emptySearchResponse(pagination), nil
 	}
 
+	if len(companyIDs) == 0 && companyID != "" {
+		s.ScheduleRefreshRecommendedTendersPageCache(companyID)
+	}
+
 	excluded, excludedByCompany, err := s.loadRecommendationExclusions(ctx, form, companyID, companyIDs)
 	if err != nil {
 		if form.ExcludeRejectedTenders {
@@ -995,7 +1014,6 @@ func (s *tenderService) Recommend(ctx context.Context, form *SearchForm, paginat
 		return nil, err
 	}
 
-	lang := s.pickResponseLanguage(form.Language)
 	now := time.Now().Unix()
 	pageResult, err := s.buildRecommendationPage(
 		ctx,