add user-id transformer for logs results cache (#7581)

**What this PR does / why we need it**:
Adding transformer to results cache same as metrics cache done in PR
#7542

pkg/querier/queryrange/log_result_cache.go

@@ -50,7 +50,8 @@ func NewLogResultCacheMetrics(registerer prometheus.Registerer) *LogResultCacheM
 // Log hits are difficult to handle because of the limit query parameter and the size of the response.
 // In the future it could be extended to cache non-empty query results.
 // see https://docs.google.com/document/d/1_mACOpxdWZ5K0cIedaja5gzMbv-m0lUVazqZd2O4mEU/edit
-func NewLogResultCache(logger log.Logger, limits Limits, cache cache.Cache, shouldCache queryrangebase.ShouldCacheFn, metrics *LogResultCacheMetrics) queryrangebase.Middleware {
+func NewLogResultCache(logger log.Logger, limits Limits, cache cache.Cache, shouldCache queryrangebase.ShouldCacheFn,
+	transformer UserIDTransformer, metrics *LogResultCacheMetrics) queryrangebase.Middleware {
 	if metrics == nil {
 		metrics = NewLogResultCacheMetrics(nil)
 	}
@@ -61,6 +62,7 @@ func NewLogResultCache(logger log.Logger, limits Limits, cache cache.Cache, shou
 			cache:       cache,
 			logger:      logger,
 			shouldCache: shouldCache,
+			transformer: transformer,
 			metrics:     metrics,
 		}
 	})
@@ -71,6 +73,7 @@ type logResultCache struct {
 	limits      Limits
 	cache       cache.Cache
 	shouldCache queryrangebase.ShouldCacheFn
+	transformer UserIDTransformer
 
 	metrics *LogResultCacheMetrics
 	logger  log.Logger
@@ -105,7 +108,17 @@ func (l *logResultCache) Do(ctx context.Context, req queryrangebase.Request) (qu
 	// The first subquery might not be aligned.
 	alignedStart := time.Unix(0, lokiReq.GetStartTs().UnixNano()-(lokiReq.GetStartTs().UnixNano()%interval.Nanoseconds()))
 	// generate the cache key based on query, tenant and start time.
-	cacheKey := fmt.Sprintf("log:%s:%s:%d:%d", tenant.JoinTenantIDs(tenantIDs), req.GetQuery(), interval.Nanoseconds(), alignedStart.UnixNano()/(interval.Nanoseconds()))
+
+	transformedTenantIDs := tenantIDs
+	if l.transformer != nil {
+		transformedTenantIDs = make([]string, 0, len(tenantIDs))
+
+		for _, tenantID := range tenantIDs {
+			transformedTenantIDs = append(transformedTenantIDs, l.transformer(ctx, tenantID))
+		}
+	}
+
+	cacheKey := fmt.Sprintf("log:%s:%s:%d:%d", tenant.JoinTenantIDs(transformedTenantIDs), req.GetQuery(), interval.Nanoseconds(), alignedStart.UnixNano()/(interval.Nanoseconds()))
 
 	_, buff, _, err := l.cache.Fetch(ctx, []string{cache.HashKey(cacheKey)})
 	if err != nil {

pkg/querier/queryrange/log_result_cache_test.go

@@ -29,6 +29,7 @@ func Test_LogResultCacheSameRange(t *testing.T) {
 			cache.NewMockCache(),
 			nil,
 			nil,
+			nil,
 		)
 	)
 
@@ -69,6 +70,7 @@ func Test_LogResultCacheSameRangeNonEmpty(t *testing.T) {
 			cache.NewMockCache(),
 			nil,
 			nil,
+			nil,
 		)
 	)
 
@@ -115,6 +117,7 @@ func Test_LogResultCacheSmallerRange(t *testing.T) {
 			cache.NewMockCache(),
 			nil,
 			nil,
+			nil,
 		)
 	)
 
@@ -161,6 +164,7 @@ func Test_LogResultCacheDifferentRange(t *testing.T) {
 			cache.NewMockCache(),
 			nil,
 			nil,
+			nil,
 		)
 	)
 
@@ -230,6 +234,7 @@ func Test_LogResultCacheDifferentRangeNonEmpty(t *testing.T) {
 			cache.NewMockCache(),
 			nil,
 			nil,
+			nil,
 		)
 	)
 
@@ -308,6 +313,7 @@ func Test_LogResultCacheDifferentRangeNonEmptyAndEmpty(t *testing.T) {
 			cache.NewMockCache(),
 			nil,
 			nil,
+			nil,
 		)
 	)
 

pkg/querier/queryrange/roundtrip.go

@@ -269,6 +269,7 @@ func NewLogFilterTripperware(
 			func(r queryrangebase.Request) bool {
 				return !r.GetCachingOptions().Disabled
 			},
+			cfg.Transformer,
 			metrics.LogResultCacheMetrics,
 		)
 		queryRangeMiddleware = append(