Added -querier.max-query-lookback and fixed -querier.max-query-into-f…

…uture (grafana#3452)

* Added querier max-query-lookback and fixed max-query-into-future

Signed-off-by: Marco Pracucci <marco@pracucci.com>

* Updated PR number

Signed-off-by: Marco Pracucci <marco@pracucci.com>

* Fixed tests

Signed-off-by: Marco Pracucci <marco@pracucci.com>

* Removed dead code

Signed-off-by: Marco Pracucci <marco@pracucci.com>

* Added warning for the deprecated flag

Signed-off-by: Marco Pracucci <marco@pracucci.com>

* Addressed review comments

Signed-off-by: Marco Pracucci <marco@pracucci.com>

chunk_store.go

@@ -8,6 +8,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/log/level"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
@@ -18,6 +19,7 @@ import (
 	"github.com/cortexproject/cortex/pkg/chunk/cache"
 	"github.com/cortexproject/cortex/pkg/util"
 	"github.com/cortexproject/cortex/pkg/util/extract"
+	"github.com/cortexproject/cortex/pkg/util/flagext"
 	"github.com/cortexproject/cortex/pkg/util/spanlogger"
 	"github.com/cortexproject/cortex/pkg/util/validation"
 )
@@ -74,11 +76,16 @@ func (cfg *StoreConfig) RegisterFlags(f *flag.FlagSet) {
 	cfg.WriteDedupeCacheConfig.RegisterFlagsWithPrefix("store.index-cache-write.", "Cache config for index entry writing. ", f)
 
 	f.Var(&cfg.CacheLookupsOlderThan, "store.cache-lookups-older-than", "Cache index entries older than this period. 0 to disable.")
-	f.Var(&cfg.MaxLookBackPeriod, "store.max-look-back-period", "Limit how long back data can be queried")
+	f.Var(&cfg.MaxLookBackPeriod, "store.max-look-back-period", "Deprecated: use -querier.max-query-lookback instead. Limit how long back data can be queried. This setting applies to chunks storage only.") // To be removed in Cortex 1.8.
 }
 
 // Validate validates the store config.
-func (cfg *StoreConfig) Validate() error {
+func (cfg *StoreConfig) Validate(logger log.Logger) error {
+	if cfg.MaxLookBackPeriod > 0 {
+		flagext.DeprecatedFlagsUsed.Inc()
+		level.Warn(logger).Log("msg", "running with DEPRECATED flag -store.max-look-back-period, use -querier.max-query-lookback instead.")
+	}
+
 	if err := cfg.ChunkCacheConfig.Validate(); err != nil {
 		return err
 	}