Add Tombstones() method to Block.

Also add Seek() to TombstoneReader

Signed-off-by: Goutham Veeramachaneni <cs14btech11014@iith.ac.in>

block.go

@@ -41,6 +41,9 @@ type DiskBlock interface {
 	// Chunks returns a ChunkReader over the block's data.
 	Chunks() ChunkReader
 
+	// Tombstones returns a TombstoneReader over the block's deleted data.
+	Tombstones() TombstoneReader
+
 	// Delete deletes data from the block.
 	Delete(mint, maxt int64, ms ...labels.Matcher) error
 
@@ -241,6 +244,10 @@ type persistedBlock struct {
 
 	chunkr *chunkReader
 	indexr *indexReader
+
+	// For tombstones.
+	stones     []uint32
+	tombstones map[uint32][]trange
 }
 
 func newPersistedBlock(dir string) (*persistedBlock, error) {
@@ -258,11 +265,23 @@ func newPersistedBlock(dir string) (*persistedBlock, error) {
 		return nil, err
 	}
 
+	tr, err := readTombstoneFile(dir)
+	if err != nil {
+		return nil, err
+	}
+	ts := make(map[uint32][]trange)
+	for tr.Next() {
+		s := tr.At()
+		ts[s.ref] = s.ranges
+	}
+
 	pb := &persistedBlock{
 		dir:    dir,
 		meta:   *meta,
 		chunkr: cr,
 		indexr: ir,
+
+		tombstones: ts,
 	}
 	return pb, nil
 }
@@ -292,7 +311,10 @@ func (pb *persistedBlock) Querier(mint, maxt int64) Querier {
 func (pb *persistedBlock) Dir() string         { return pb.dir }
 func (pb *persistedBlock) Index() IndexReader  { return pb.indexr }
 func (pb *persistedBlock) Chunks() ChunkReader { return pb.chunkr }
-func (pb *persistedBlock) Meta() BlockMeta     { return pb.meta }
+func (pb *persistedBlock) Tombstones() TombstoneReader {
+	return newMapTombstoneReader(pb.tombstones)
+}
+func (pb *persistedBlock) Meta() BlockMeta { return pb.meta }
 
 func (pb *persistedBlock) Delete(mint, maxt int64, ms ...labels.Matcher) error {
 	pr := newPostingsReader(pb.indexr)
@@ -348,6 +370,7 @@ type stone struct {
 // TombstoneReader is the iterator over tombstones.
 type TombstoneReader interface {
 	Next() bool
+	Seek(ref uint32) bool
 	At() stone
 	Err() error
 }
@@ -402,6 +425,16 @@ func (t *tombstoneReader) Next() bool {
 	return t.idx < t.len
 }
 
+func (t *tombstoneReader) Seek(ref uint32) bool {
+	bytIdx := t.idx * 12
+
+	t.idx += sort.Search(t.len-t.idx, func(i int) bool {
+		return binary.BigEndian.Uint32(t.b[bytIdx+i*12:]) >= ref
+	})
+
+	return t.idx < t.len
+}
+
 func (t *tombstoneReader) At() stone {
 	bytIdx := t.idx * (4 + 8)
 	dat := t.stones[bytIdx : bytIdx+12]
@@ -443,6 +476,7 @@ type mapTombstoneReader struct {
 	stones map[uint32][]trange
 }
 
+// TODO(gouthamve): Take pre-sorted refs.
 func newMapTombstoneReader(ts map[uint32][]trange) *mapTombstoneReader {
 	refs := make([]uint32, 0, len(ts))
 	for k := range ts {
@@ -463,6 +497,25 @@ func (t *mapTombstoneReader) Next() bool {
 	return false
 }
 
+func (t *mapTombstoneReader) Seek(ref uint32) bool {
+	// If the current value satisfies, then return.
+	if t.cur >= ref {
+		return true
+	}
+
+	// Do binary search between current position and end.
+	i := sort.Search(len(t.refs), func(i int) bool {
+		return t.refs[i] >= ref
+	})
+	if i < len(t.refs) {
+		t.cur = t.refs[i]
+		t.refs = t.refs[i+1:]
+		return true
+	}
+	t.refs = nil
+	return false
+}
+
 func (t *mapTombstoneReader) At() stone {
 	return stone{ref: t.cur, ranges: t.stones[t.cur]}
 }
@@ -492,6 +545,25 @@ func (t *simpleTombstoneReader) Next() bool {
 	return false
 }
 
+func (t *simpleTombstoneReader) Seek(ref uint32) bool {
+	// If the current value satisfies, then return.
+	if t.cur >= ref {
+		return true
+	}
+
+	// Do binary search between current position and end.
+	i := sort.Search(len(t.refs), func(i int) bool {
+		return t.refs[i] >= ref
+	})
+	if i < len(t.refs) {
+		t.cur = t.refs[i]
+		t.refs = t.refs[i+1:]
+		return true
+	}
+	t.refs = nil
+	return false
+}
+
 func (t *simpleTombstoneReader) At() stone {
 	return stone{ref: t.cur, ranges: t.ranges}
 }
@@ -554,6 +626,17 @@ func (t *mergedTombstoneReader) Next() bool {
 	return true
 }
 
+func (t *mergedTombstoneReader) Seek(ref uint32) bool {
+	if t.cur.ref >= ref {
+		return true
+	}
+
+	t.aok = t.a.Seek(ref)
+	t.bok = t.b.Seek(ref)
+	t.initialized = true
+
+	return t.Next()
+}
 func (t *mergedTombstoneReader) At() stone {
 	return t.cur
 }

head.go

@@ -210,19 +210,24 @@ func (h *HeadBlock) Meta() BlockMeta {
 	return m
 }
 
-// Dir implements headBlock
+// Dir implements headBlock.
 func (h *HeadBlock) Dir() string { return h.dir }
 
-// Persisted implements headBlock
+// Persisted implements headBlock.
 func (h *HeadBlock) Persisted() bool { return false }
 
-// Index implements headBlock
+// Index implements headBlock.
 func (h *HeadBlock) Index() IndexReader { return &headIndexReader{h} }
 
-// Chunks implements headBlock
+// Chunks implements headBlock.
 func (h *HeadBlock) Chunks() ChunkReader { return &headChunkReader{h} }
 
-// Delete implements headBlock
+// Tombstones implements headBlock.
+func (h *HeadBlock) Tombstones() TombstoneReader {
+	return newMapTombstoneReader(h.tombstones)
+}
+
+// Delete implements headBlock.
 func (h *HeadBlock) Delete(mint int64, maxt int64, ms ...labels.Matcher) error {
 	h.mtx.RLock()
 
@@ -246,13 +251,7 @@ Outer:
 			}
 		}
 
-		rs, ok := h.tombstones[ref]
-		if !ok {
-			h.tombstones[ref] = []trange{{mint, maxt}}
-			continue
-		}
-
-		h.tombstones[ref] = addNewInterval(rs, trange{mint, maxt})
+		h.tombstones[ref] = addNewInterval(h.tombstones[ref], trange{mint, maxt})
 	}
 
 	if p.Err() != nil {
@@ -262,7 +261,7 @@ Outer:
 	return writeTombstoneFile(h.dir, newMapTombstoneReader(h.tombstones))
 }
 
-// Querier implements Queryable and headBlock
+// Querier implements Queryable and headBlock.
 func (h *HeadBlock) Querier(mint, maxt int64) Querier {
 	h.mtx.RLock()
 	defer h.mtx.RUnlock()

querier.go

@@ -126,8 +126,9 @@ func (q *querier) Close() error {
 
 // blockQuerier provides querying access to a single block database.
 type blockQuerier struct {
-	index  IndexReader
-	chunks ChunkReader
+	index      IndexReader
+	chunks     ChunkReader
+	tombstones TombstoneReader
 
 	postingsMapper func(Postings) Postings