feat: add FileStore.TimeRange

tsdb/engine.go

@@ -83,6 +83,8 @@ type Engine interface {
 	DiskSize() int64
 	IsIdle() (bool, string)
 	Free() error
+	// TimeRange will return the min/max time range of shard
+	TimeRange() (int64, int64)
 
 	io.WriterTo
 }

tsdb/engine/tsm1/engine.go

@@ -677,6 +677,11 @@ func (e *Engine) LastModified() time.Time {
 	return fsTime
 }
 
+// TimeRange returns the min and max time range for this shard
+func (e *Engine) TimeRange() (int64, int64) {
+	return e.FileStore.TimeRange()
+}
+
 // EngineStatistics maintains statistics for the engine.
 type EngineStatistics struct {
 	CacheCompactions        int64 // Counter of cache compactions that have ever run.

tsdb/engine/tsm1/file_store.go

@@ -1080,6 +1080,27 @@ func (f *FileStore) LastModified() time.Time {
 	return f.lastModified
 }
 
+// TimeRange returns the minimum and maximum times across all TSM files in the FileStore.
+// Returns (math.MaxInt64, math.MinInt64) if there are no files.
+func (f *FileStore) TimeRange() (min, max int64) {
+	f.mu.RLock()
+	defer f.mu.RUnlock()
+
+	min, max = math.MaxInt64, math.MinInt64
+
+	for _, file := range f.files {
+		fileMin, fileMax := file.TimeRange()
+		if fileMin < min {
+			min = fileMin
+		}
+		if fileMax > max {
+			max = fileMax
+		}
+	}
+
+	return min, max
+}
+
 // We need to determine the possible files that may be accessed by this query given
 // the time range.
 func (f *FileStore) cost(key []byte, min, max int64) query.IteratorCost {

tsdb/shard.go

@@ -474,6 +474,16 @@ func (s *Shard) LastModifiedWithErr() (time.Time, error) {
 	return engine.LastModified(), nil
 }
 
+func (s *Shard) TimeRange() (int64, int64, error) {
+	engine, err := s.Engine()
+	if err != nil {
+		return int64(0), int64(0), fmt.Errorf("failed getting shard %d time range: %w", s.id, err)
+	}
+
+	minT, maxT := engine.TimeRange()
+	return minT, maxT, nil
+}
+
 // Index returns a reference to the underlying index. It returns an error if
 // the index is nil.
 func (s *Shard) Index() (Index, error) {

tsdb/shard_internal_test.go

@@ -2,6 +2,7 @@ package tsdb
 
 import (
 	"fmt"
+	"math"
 	"os"
 	"path"
 	"path/filepath"
@@ -301,3 +302,32 @@ func (sh *TempShard) MustWritePointsString(s string) {
 		panic(err)
 	}
 }
+
+func TestShard_TimeRange(t *testing.T) {
+	for _, index := range RegisteredIndexes() {
+		t.Run(index, func(t *testing.T) {
+			sh := NewTempShard(index)
+			defer CloseShard(t, sh)
+
+			require.NoError(t, sh.Open())
+
+			min, max, err := sh.TimeRange()
+			require.NoError(t, err)
+			require.Equal(t, int64(math.MaxInt64), min)
+			require.Equal(t, int64(math.MinInt64), max)
+
+			sh.MustWritePointsString(`
+cpu value=100 1000000000
+cpu value=200 2000000000
+mem value=300 1500000000`)
+
+			// Force flush WAL to TSM files
+			require.NoError(t, sh.ScheduleFullCompaction())
+
+			min, max, err = sh.TimeRange()
+			require.NoError(t, err)
+			require.Equal(t, int64(1000000000000000000), min)
+			require.Equal(t, int64(2000000000000000000), max)
+		})
+	}
+}