Adding upstream version 2.5.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

index/upsidedown/store/metrics/store.go

@@ -0,0 +1,277 @@
+//  Copyright (c) 2015 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package metrics provides a bleve.store.KVStore implementation that
+// wraps another, real KVStore implementation, and uses go-metrics to
+// track runtime performance metrics.
+package metrics
+
+import (
+	"container/list"
+	"encoding/json"
+	"fmt"
+	"io"
+	"sync"
+	"time"
+
+	"github.com/blevesearch/bleve/v2/registry"
+	"github.com/blevesearch/bleve/v2/util"
+	"github.com/blevesearch/go-metrics"
+	store "github.com/blevesearch/upsidedown_store_api"
+)
+
+const Name = "metrics"
+
+type Store struct {
+	o store.KVStore
+
+	timerReaderGet            metrics.Timer
+	timerReaderMultiGet       metrics.Timer
+	timerReaderPrefixIterator metrics.Timer
+	timerReaderRangeIterator  metrics.Timer
+	timerWriterExecuteBatch   metrics.Timer
+	timerIteratorSeek         metrics.Timer
+	timerIteratorNext         metrics.Timer
+	timerBatchMerge           metrics.Timer
+
+	m      sync.Mutex // Protects the fields that follow.
+	errors *list.List // Capped list of StoreError's.
+
+	s *stats
+}
+
+func New(mo store.MergeOperator, config map[string]interface{}) (store.KVStore, error) {
+
+	name, ok := config["kvStoreName_actual"].(string)
+	if !ok || name == "" {
+		return nil, fmt.Errorf("metrics: missing kvStoreName_actual,"+
+			" config: %#v", config)
+	}
+
+	if name == Name {
+		return nil, fmt.Errorf("metrics: circular kvStoreName_actual")
+	}
+
+	ctr := registry.KVStoreConstructorByName(name)
+	if ctr == nil {
+		return nil, fmt.Errorf("metrics: no kv store constructor,"+
+			" kvStoreName_actual: %s", name)
+	}
+
+	kvs, err := ctr(mo, config)
+	if err != nil {
+		return nil, err
+	}
+
+	rv := &Store{
+		o: kvs,
+
+		timerReaderGet:            metrics.NewTimer(),
+		timerReaderMultiGet:       metrics.NewTimer(),
+		timerReaderPrefixIterator: metrics.NewTimer(),
+		timerReaderRangeIterator:  metrics.NewTimer(),
+		timerWriterExecuteBatch:   metrics.NewTimer(),
+		timerIteratorSeek:         metrics.NewTimer(),
+		timerIteratorNext:         metrics.NewTimer(),
+		timerBatchMerge:           metrics.NewTimer(),
+
+		errors: list.New(),
+	}
+
+	rv.s = &stats{s: rv}
+
+	return rv, nil
+}
+
+func init() {
+	err := registry.RegisterKVStore(Name, New)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func (s *Store) Close() error {
+	return s.o.Close()
+}
+
+func (s *Store) Reader() (store.KVReader, error) {
+	o, err := s.o.Reader()
+	if err != nil {
+		s.AddError("Reader", err, nil)
+		return nil, err
+	}
+	return &Reader{s: s, o: o}, nil
+}
+
+func (s *Store) Writer() (store.KVWriter, error) {
+	o, err := s.o.Writer()
+	if err != nil {
+		s.AddError("Writer", err, nil)
+		return nil, err
+	}
+	return &Writer{s: s, o: o}, nil
+}
+
+// Metric specific code below:
+
+const MaxErrors = 100
+
+type StoreError struct {
+	Time string
+	Op   string
+	Err  string
+	Key  string
+}
+
+func (s *Store) AddError(op string, err error, key []byte) {
+	e := &StoreError{
+		Time: time.Now().Format(time.RFC3339Nano),
+		Op:   op,
+		Err:  fmt.Sprintf("%v", err),
+		Key:  string(key),
+	}
+
+	s.m.Lock()
+	for s.errors.Len() >= MaxErrors {
+		s.errors.Remove(s.errors.Front())
+	}
+	s.errors.PushBack(e)
+	s.m.Unlock()
+}
+
+func (s *Store) WriteJSON(w io.Writer) (err error) {
+	_, err = w.Write([]byte(`{"TimerReaderGet":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerReaderGet)
+	_, err = w.Write([]byte(`,"TimerReaderMultiGet":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerReaderMultiGet)
+	_, err = w.Write([]byte(`,"TimerReaderPrefixIterator":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerReaderPrefixIterator)
+	_, err = w.Write([]byte(`,"TimerReaderRangeIterator":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerReaderRangeIterator)
+	_, err = w.Write([]byte(`,"TimerWriterExecuteBatch":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerWriterExecuteBatch)
+	_, err = w.Write([]byte(`,"TimerIteratorSeek":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerIteratorSeek)
+	_, err = w.Write([]byte(`,"TimerIteratorNext":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerIteratorNext)
+	_, err = w.Write([]byte(`,"TimerBatchMerge":`))
+	if err != nil {
+		return
+	}
+	WriteTimerJSON(w, s.timerBatchMerge)
+
+	_, err = w.Write([]byte(`,"Errors":[`))
+	if err != nil {
+		return
+	}
+	s.m.Lock()
+	defer s.m.Unlock()
+	e := s.errors.Front()
+	i := 0
+	for e != nil {
+		se, ok := e.Value.(*StoreError)
+		if ok && se != nil {
+			if i > 0 {
+				_, err = w.Write([]byte(","))
+				if err != nil {
+					return
+				}
+			}
+			var buf []byte
+			buf, err = util.MarshalJSON(se)
+			if err == nil {
+				_, err = w.Write(buf)
+				if err != nil {
+					return
+				}
+			}
+		}
+		e = e.Next()
+		i = i + 1
+	}
+	_, err = w.Write([]byte(`]`))
+	if err != nil {
+		return
+	}
+
+	// see if the underlying implementation has its own stats
+	if o, ok := s.o.(store.KVStoreStats); ok {
+		storeStats := o.Stats()
+		var storeBytes []byte
+		storeBytes, err = util.MarshalJSON(storeStats)
+		if err != nil {
+			return
+		}
+		_, err = fmt.Fprintf(w, `, "store": %s`, string(storeBytes))
+		if err != nil {
+			return
+		}
+	}
+
+	_, err = w.Write([]byte(`}`))
+	if err != nil {
+		return
+	}
+
+	return
+}
+
+func (s *Store) WriteCSVHeader(w io.Writer) {
+	WriteTimerCSVHeader(w, "TimerReaderGet")
+	WriteTimerCSVHeader(w, "TimerReaderPrefixIterator")
+	WriteTimerCSVHeader(w, "TimerReaderRangeIterator")
+	WriteTimerCSVHeader(w, "TimerWtierExecuteBatch")
+	WriteTimerCSVHeader(w, "TimerIteratorSeek")
+	WriteTimerCSVHeader(w, "TimerIteratorNext")
+	WriteTimerCSVHeader(w, "TimerBatchMerge")
+}
+
+func (s *Store) WriteCSV(w io.Writer) {
+	WriteTimerCSV(w, s.timerReaderGet)
+	WriteTimerCSV(w, s.timerReaderPrefixIterator)
+	WriteTimerCSV(w, s.timerReaderRangeIterator)
+	WriteTimerCSV(w, s.timerWriterExecuteBatch)
+	WriteTimerCSV(w, s.timerIteratorSeek)
+	WriteTimerCSV(w, s.timerIteratorNext)
+	WriteTimerCSV(w, s.timerBatchMerge)
+}
+
+func (s *Store) Stats() json.Marshaler {
+	return s.s
+}
+
+func (s *Store) StatsMap() map[string]interface{} {
+	return s.s.statsMap()
+}