simplify packages under tsdb

tsdb/engine/tsm1/encoding.go

@@ -444,11 +444,7 @@ func DecodeFloatBlock(block []byte, a *[]FloatValue) ([]FloatValue, error) {
 		}
 
 		// Did float decoding have an error?
-		err = vdec.Error()
-		if err != nil {
-			return err
-		}
-		return nil
+		return vdec.Error()
 	}(*a)
 
 	timeDecoderPool.Put(tdec)
@@ -575,11 +571,7 @@ func DecodeBooleanBlock(block []byte, a *[]BooleanValue) ([]BooleanValue, error)
 			return err
 		}
 		// Did boolean decoding have an error?
-		err = vdec.Error()
-		if err != nil {
-			return err
-		}
-		return nil
+		return vdec.Error()
 	}(*a)
 
 	timeDecoderPool.Put(tdec)
@@ -698,11 +690,7 @@ func DecodeIntegerBlock(block []byte, a *[]IntegerValue) ([]IntegerValue, error)
 			return err
 		}
 		// Did int64 decoding have an error?
-		err = vdec.Error()
-		if err != nil {
-			return err
-		}
-		return nil
+		return vdec.Error()
 	}(*a)
 
 	timeDecoderPool.Put(tdec)
@@ -821,11 +809,7 @@ func DecodeUnsignedBlock(block []byte, a *[]UnsignedValue) ([]UnsignedValue, err
 			return err
 		}
 		// Did int64 decoding have an error?
-		err = vdec.Error()
-		if err != nil {
-			return err
-		}
-		return nil
+		return vdec.Error()
 	}(*a)
 
 	timeDecoderPool.Put(tdec)
@@ -947,11 +931,7 @@ func DecodeStringBlock(block []byte, a *[]StringValue) ([]StringValue, error) {
 			return err
 		}
 		// Did string decoding have an error?
-		err = vdec.Error()
-		if err != nil {
-			return err
-		}
-		return nil
+		return vdec.Error()
 	}(*a)
 
 	timeDecoderPool.Put(tdec)

tsdb/engine/tsm1/engine.go

@@ -868,8 +868,7 @@ func (e *Engine) filterFileToBackup(r *TSMReader, fi os.FileInfo, shardRelativeP
 	defer w.Close()
 
 	// implicit else: here we iterate over the blocks and only keep the ones we really want.
-	var bi *BlockIterator
-	bi = r.BlockIterator()
+	bi := r.BlockIterator()
 
 	for bi.Next() {
 		// not concerned with typ or checksum since we are just blindly writing back, with no decoding
@@ -1298,10 +1297,7 @@ func (e *Engine) deleteSeriesRange(seriesKeys [][]byte, min, max int64) error {
 			}
 		}
 
-		if err := batch.Commit(); err != nil {
-			return err
-		}
-		return nil
+		return batch.Commit()
 	}); err != nil {
 		return err
 	}

tsdb/engine/tsm1/file_store_key_iterator.go

@@ -84,7 +84,7 @@ RETRY:
 		}
 	}
 
-	if merging && bytes.Compare(m.key, key) == 0 {
+	if merging && bytes.Equal(m.key, key) {
 		// same as previous key, keep iterating
 		goto RETRY
 	}

tsdb/engine/tsm1/reader.go

@@ -1451,11 +1451,7 @@ func (m *mmapAccessor) rename(path string) error {
 	}
 
 	m.b, err = mmap(m.f, 0, int(stat.Size()))
-	if err != nil {
-		return err
-	}
-
-	return nil
+	return err
 }
 
 func (m *mmapAccessor) read(key []byte, timestamp int64) ([]Value, error) {

tsdb/engine/tsm1/tombstone.go

@@ -693,8 +693,6 @@ func (t *Tombstoner) writeTombstone(dst io.Writer, ts Tombstone) error {
 	}
 
 	binary.BigEndian.PutUint64(t.tmp[:], uint64(ts.Max))
-	if _, err := dst.Write(t.tmp[:]); err != nil {
-		return err
-	}
-	return nil
+	_, err := dst.Write(t.tmp[:])
+	return err
 }

tsdb/index/tsi1/index_test.go

@@ -363,10 +363,7 @@ func (idx *Index) Reopen() error {
 	partitionN := idx.Index.PartitionN // Remember how many partitions to use.
 	idx.Index = tsi1.NewIndex(idx.SeriesFile.SeriesFile, tsi1.WithPath(idx.Index.Path()))
 	idx.Index.PartitionN = partitionN
-	if err := idx.Open(); err != nil {
-		return err
-	}
-	return nil
+	return idx.Open()
 }
 
 // Run executes a subtest for each of several different states:

tsdb/index/tsi1/measurement_block.go

@@ -525,11 +525,7 @@ func (mw *MeasurementBlockWriter) WriteTo(w io.Writer) (n int64, err error) {
 	// Write trailer.
 	nn, err := t.WriteTo(w)
 	n += nn
-	if err != nil {
-		return n, err
-	}
-
-	return n, nil
+	return n, err
 }
 
 // writeMeasurementTo encodes a single measurement entry into w.
@@ -577,11 +573,8 @@ func (mw *MeasurementBlockWriter) writeMeasurementTo(w io.Writer, name []byte, m
 		return err
 	}
 	nn, err := mw.buf.WriteTo(w)
-	if *n += nn; err != nil {
-		return err
-	}
-
-	return nil
+	*n += nn
+	return err
 }
 
 // writeSketchTo writes an estimator.Sketch into w, updating the number of bytes

tsdb/index/tsi1/partition.go

@@ -613,10 +613,7 @@ func (i *Partition) DropSeries(seriesID uint64) error {
 	i.seriesIDSet.Remove(seriesID)
 
 	// Swap log file, if necessary.
-	if err := i.CheckLogFile(); err != nil {
-		return err
-	}
-	return nil
+	return i.CheckLogFile()
 }
 
 // MeasurementsSketches returns the two sketches for the index by merging all
@@ -1067,8 +1064,6 @@ func (i *Partition) compactLogFile(logFile *LogFile) {
 		logger.Error("cannot remove log file", zap.Error(err))
 		return
 	}
-
-	return
 }
 
 // unionStringSets returns the union of two sets

tsdb/index/tsi1/tag_block.go

@@ -644,11 +644,7 @@ func (enc *TagBlockEncoder) Close() error {
 	// Write trailer.
 	nn, err := enc.trailer.WriteTo(enc.w)
 	enc.n += nn
-	if err != nil {
-		return err
-	}
-
-	return nil
+	return err
 }
 
 // ensureHeaderWritten writes a single byte to offset the rest of the block.

tsdb/shard.go

@@ -1477,10 +1477,7 @@ func NewMeasurementFieldSet(path string) (*MeasurementFieldSet, error) {
 
 	// If there is a load error, return the error and an empty set so
 	// it can be rebuild manually.
-	if err := fs.load(); err != nil {
-		return fs, err
-	}
-	return fs, nil
+	return fs, fs.load()
 }
 
 // Fields returns fields for a measurement by name.

tsdb/store.go

@@ -727,10 +727,7 @@ func (s *Store) DeleteMeasurement(database, name string) error {
 		limit.Take()
 		defer limit.Release()
 
-		if err := sh.DeleteMeasurement([]byte(name)); err != nil {
-			return err
-		}
-		return nil
+		return sh.DeleteMeasurement([]byte(name))
 	})
 }
 
@@ -1008,7 +1005,7 @@ func (s *Store) DeleteSeries(database string, sources []influxql.Source, conditi
 	a, err := s.ExpandSources(sources)
 	if err != nil {
 		return err
-	} else if sources != nil && len(sources) != 0 && len(a) == 0 {
+	} else if len(sources) > 0 && len(a) == 0 {
 		return nil
 	}
 	sources = a