Commit a14f791d authored by Marcin Wielgus's avatar Marcin Wielgus

Revert "Merge pull request #20329 from kubernetes/revert-20323-bump-influxdb"

This reverts commit b4188ec4, reversing changes made to 28951bd6.
parent 3e04a45a
......@@ -48,6 +48,10 @@
"Rev": "5d54e27f1764a0309eafe12c9df7bac03f241646"
},
{
"ImportPath": "github.com/armon/go-metrics",
"Rev": "345426c77237ece5dab0e1605c3e4b35c3f54757"
},
{
"ImportPath": "github.com/aws/aws-sdk-go/aws",
"Comment": "v1.0.7",
"Rev": "bf2f8fe7f45e68017086d069498638893feddf64"
......@@ -680,6 +684,18 @@
"Rev": "8096f47503459bcc74d1f4c487b7e6e42e5746b5"
},
{
"ImportPath": "github.com/hashicorp/go-msgpack/codec",
"Rev": "fa3f63826f7c23912c15263591e65d54d080b458"
},
{
"ImportPath": "github.com/hashicorp/raft",
"Rev": "057b893fd996696719e98b6c44649ea14968c811"
},
{
"ImportPath": "github.com/hashicorp/raft-boltdb",
"Rev": "d1e82c1ec3f15ee991f7cc7ffd5b67ff6f5bbaee"
},
{
"ImportPath": "github.com/imdario/mergo",
"Comment": "0.1.3-8-g6633656",
"Rev": "6633656539c1639d9d78127b7d47c622b5d7b6dc"
......@@ -690,8 +706,33 @@
},
{
"ImportPath": "github.com/influxdb/influxdb/client",
"Comment": "v0.8.8",
"Rev": "afde71eb1740fd763ab9450e1f700ba0e53c36d0"
"Comment": "v0.9.2.1",
"Rev": "b237c68bab4756507baf6840023be103853e77db"
},
{
"ImportPath": "github.com/influxdb/influxdb/influxql",
"Comment": "v0.9.2.1",
"Rev": "b237c68bab4756507baf6840023be103853e77db"
},
{
"ImportPath": "github.com/influxdb/influxdb/meta",
"Comment": "v0.9.2.1",
"Rev": "b237c68bab4756507baf6840023be103853e77db"
},
{
"ImportPath": "github.com/influxdb/influxdb/snapshot",
"Comment": "v0.9.2.1",
"Rev": "b237c68bab4756507baf6840023be103853e77db"
},
{
"ImportPath": "github.com/influxdb/influxdb/toml",
"Comment": "v0.9.2.1",
"Rev": "b237c68bab4756507baf6840023be103853e77db"
},
{
"ImportPath": "github.com/influxdb/influxdb/tsdb",
"Comment": "v0.9.2.1",
"Rev": "b237c68bab4756507baf6840023be103853e77db"
},
{
"ImportPath": "github.com/jmespath/go-jmespath",
......
......@@ -8,6 +8,7 @@ bitbucket.org/ww/goautoneg | spdxBSD3
github.com/abbot/go-http-auth | Apache-2
github.com/appc/cni | Apache-2
github.com/appc/spec | Apache-2
github.com/armon/go-metrics | MITname
github.com/aws/aws-sdk-go | Apache-2
github.com/beorn7/perks/quantile | MIT?
github.com/blang/semver | MITname
......@@ -50,6 +51,9 @@ github.com/google/cadvisor | Apache-2
github.com/google/gofuzz | Apache-2
github.com/gorilla/context | spdxBSD3
github.com/gorilla/mux | spdxBSD3
github.com/hashicorp/go-msgpack | spdxBSD3
github.com/hashicorp/raft | IntelPart08
github.com/hashicorp/raft-boltdb | IntelPart08
github.com/imdario/mergo | spdxBSD3
github.com/inconshreveable/mousetrap | Apache-2
github.com/influxdb/influxdb | MITname
......
# Compiled Object files, Static and Dynamic libs (Shared Objects)
*.o
*.a
*.so
# Folders
_obj
_test
# Architecture specific extensions/prefixes
*.[568vq]
[568vq].out
*.cgo1.go
*.cgo2.c
_cgo_defun.c
_cgo_gotypes.go
_cgo_export.*
_testmain.go
*.exe
The MIT License (MIT)
Copyright (c) 2013 Armon Dadgar
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
go-metrics
==========
This library provides a `metrics` package which can be used to instrument code,
expose application metrics, and profile runtime performance in a flexible manner.
Current API: [![GoDoc](https://godoc.org/github.com/armon/go-metrics?status.svg)](https://godoc.org/github.com/armon/go-metrics)
Sinks
=====
The `metrics` package makes use of a `MetricSink` interface to support delivery
to any type of backend. Currently the following sinks are provided:
* StatsiteSink : Sinks to a [statsite](https://github.com/armon/statsite/) instance (TCP)
* StatsdSink: Sinks to a [StatsD](https://github.com/etsy/statsd/) / statsite instance (UDP)
* PrometheusSink: Sinks to a [Prometheus](http://prometheus.io/) metrics endpoint (exposed via HTTP for scrapes)
* InmemSink : Provides in-memory aggregation, can be used to export stats
* FanoutSink : Sinks to multiple sinks. Enables writing to multiple statsite instances for example.
* BlackholeSink : Sinks to nowhere
In addition to the sinks, the `InmemSignal` can be used to catch a signal,
and dump a formatted output of recent metrics. For example, when a process gets
a SIGUSR1, it can dump to stderr recent performance metrics for debugging.
Examples
========
Here is an example of using the package:
func SlowMethod() {
// Profiling the runtime of a method
defer metrics.MeasureSince([]string{"SlowMethod"}, time.Now())
}
// Configure a statsite sink as the global metrics sink
sink, _ := metrics.NewStatsiteSink("statsite:8125")
metrics.NewGlobal(metrics.DefaultConfig("service-name"), sink)
// Emit a Key/Value pair
metrics.EmitKey([]string{"questions", "meaning of life"}, 42)
Here is an example of setting up an signal handler:
// Setup the inmem sink and signal handler
inm := metrics.NewInmemSink(10*time.Second, time.Minute)
sig := metrics.DefaultInmemSignal(inm)
metrics.NewGlobal(metrics.DefaultConfig("service-name"), inm)
// Run some code
inm.SetGauge([]string{"foo"}, 42)
inm.EmitKey([]string{"bar"}, 30)
inm.IncrCounter([]string{"baz"}, 42)
inm.IncrCounter([]string{"baz"}, 1)
inm.IncrCounter([]string{"baz"}, 80)
inm.AddSample([]string{"method", "wow"}, 42)
inm.AddSample([]string{"method", "wow"}, 100)
inm.AddSample([]string{"method", "wow"}, 22)
....
When a signal comes in, output like the following will be dumped to stderr:
[2014-01-28 14:57:33.04 -0800 PST][G] 'foo': 42.000
[2014-01-28 14:57:33.04 -0800 PST][P] 'bar': 30.000
[2014-01-28 14:57:33.04 -0800 PST][C] 'baz': Count: 3 Min: 1.000 Mean: 41.000 Max: 80.000 Stddev: 39.509
[2014-01-28 14:57:33.04 -0800 PST][S] 'method.wow': Count: 3 Min: 22.000 Mean: 54.667 Max: 100.000 Stddev: 40.513
// +build !windows
package metrics
import (
"syscall"
)
const (
// DefaultSignal is used with DefaultInmemSignal
DefaultSignal = syscall.SIGUSR1
)
// +build windows
package metrics
import (
"syscall"
)
const (
// DefaultSignal is used with DefaultInmemSignal
// Windows has no SIGUSR1, use SIGBREAK
DefaultSignal = syscall.Signal(21)
)
package datadog
import (
"fmt"
"strings"
"github.com/DataDog/datadog-go/statsd"
)
// DogStatsdSink provides a MetricSink that can be used
// with a dogstatsd server. It utilizes the Dogstatsd client at github.com/DataDog/datadog-go/statsd
type DogStatsdSink struct {
client *statsd.Client
hostName string
propagateHostname bool
}
// NewDogStatsdSink is used to create a new DogStatsdSink with sane defaults
func NewDogStatsdSink(addr string, hostName string) (*DogStatsdSink, error) {
client, err := statsd.New(addr)
if err != nil {
return nil, err
}
sink := &DogStatsdSink{
client: client,
hostName: hostName,
propagateHostname: false,
}
return sink, nil
}
// SetTags sets common tags on the Dogstatsd Client that will be sent
// along with all dogstatsd packets.
// Ref: http://docs.datadoghq.com/guides/dogstatsd/#tags
func (s *DogStatsdSink) SetTags(tags []string) {
s.client.Tags = tags
}
// EnableHostnamePropagation forces a Dogstatsd `host` tag with the value specified by `s.HostName`
// Since the go-metrics package has its own mechanism for attaching a hostname to metrics,
// setting the `propagateHostname` flag ensures that `s.HostName` overrides the host tag naively set by the DogStatsd server
func (s *DogStatsdSink) EnableHostNamePropagation() {
s.propagateHostname = true
}
func (s *DogStatsdSink) flattenKey(parts []string) string {
joined := strings.Join(parts, ".")
return strings.Map(func(r rune) rune {
switch r {
case ':':
fallthrough
case ' ':
return '_'
default:
return r
}
}, joined)
}
func (s *DogStatsdSink) parseKey(key []string) ([]string, []string) {
// Since DogStatsd supports dimensionality via tags on metric keys, this sink's approach is to splice the hostname out of the key in favor of a `host` tag
// The `host` tag is either forced here, or set downstream by the DogStatsd server
var tags []string
hostName := s.hostName
//Splice the hostname out of the key
for i, el := range key {
if el == hostName {
key = append(key[:i], key[i+1:]...)
}
}
if s.propagateHostname {
tags = append(tags, fmt.Sprintf("host:%s", hostName))
}
return key, tags
}
// Implementation of methods in the MetricSink interface
func (s *DogStatsdSink) SetGauge(key []string, val float32) {
s.SetGaugeWithTags(key, val, []string{})
}
func (s *DogStatsdSink) IncrCounter(key []string, val float32) {
s.IncrCounterWithTags(key, val, []string{})
}
// EmitKey is not implemented since DogStatsd does not provide a metric type that holds an
// arbitrary number of values
func (s *DogStatsdSink) EmitKey(key []string, val float32) {
}
func (s *DogStatsdSink) AddSample(key []string, val float32) {
s.AddSampleWithTags(key, val, []string{})
}
// The following ...WithTags methods correspond to Datadog's Tag extension to Statsd.
// http://docs.datadoghq.com/guides/dogstatsd/#tags
func (s *DogStatsdSink) SetGaugeWithTags(key []string, val float32, tags []string) {
flatKey, tags := s.getFlatkeyAndCombinedTags(key, tags)
rate := 1.0
s.client.Gauge(flatKey, float64(val), tags, rate)
}
func (s *DogStatsdSink) IncrCounterWithTags(key []string, val float32, tags []string) {
flatKey, tags := s.getFlatkeyAndCombinedTags(key, tags)
rate := 1.0
s.client.Count(flatKey, int64(val), tags, rate)
}
func (s *DogStatsdSink) AddSampleWithTags(key []string, val float32, tags []string) {
flatKey, tags := s.getFlatkeyAndCombinedTags(key, tags)
rate := 1.0
s.client.TimeInMilliseconds(flatKey, float64(val), tags, rate)
}
func (s *DogStatsdSink) getFlatkeyAndCombinedTags(key []string, tags []string) (flattenedKey string, combinedTags []string) {
key, hostTags := s.parseKey(key)
flatKey := s.flattenKey(key)
tags = append(tags, hostTags...)
return flatKey, tags
}
package metrics
import (
"fmt"
"math"
"strings"
"sync"
"time"
)
// InmemSink provides a MetricSink that does in-memory aggregation
// without sending metrics over a network. It can be embedded within
// an application to provide profiling information.
type InmemSink struct {
// How long is each aggregation interval
interval time.Duration
// Retain controls how many metrics interval we keep
retain time.Duration
// maxIntervals is the maximum length of intervals.
// It is retain / interval.
maxIntervals int
// intervals is a slice of the retained intervals
intervals []*IntervalMetrics
intervalLock sync.RWMutex
}
// IntervalMetrics stores the aggregated metrics
// for a specific interval
type IntervalMetrics struct {
sync.RWMutex
// The start time of the interval
Interval time.Time
// Gauges maps the key to the last set value
Gauges map[string]float32
// Points maps the string to the list of emitted values
// from EmitKey
Points map[string][]float32
// Counters maps the string key to a sum of the counter
// values
Counters map[string]*AggregateSample
// Samples maps the key to an AggregateSample,
// which has the rolled up view of a sample
Samples map[string]*AggregateSample
}
// NewIntervalMetrics creates a new IntervalMetrics for a given interval
func NewIntervalMetrics(intv time.Time) *IntervalMetrics {
return &IntervalMetrics{
Interval: intv,
Gauges: make(map[string]float32),
Points: make(map[string][]float32),
Counters: make(map[string]*AggregateSample),
Samples: make(map[string]*AggregateSample),
}
}
// AggregateSample is used to hold aggregate metrics
// about a sample
type AggregateSample struct {
Count int // The count of emitted pairs
Sum float64 // The sum of values
SumSq float64 // The sum of squared values
Min float64 // Minimum value
Max float64 // Maximum value
LastUpdated time.Time // When value was last updated
}
// Computes a Stddev of the values
func (a *AggregateSample) Stddev() float64 {
num := (float64(a.Count) * a.SumSq) - math.Pow(a.Sum, 2)
div := float64(a.Count * (a.Count - 1))
if div == 0 {
return 0
}
return math.Sqrt(num / div)
}
// Computes a mean of the values
func (a *AggregateSample) Mean() float64 {
if a.Count == 0 {
return 0
}
return a.Sum / float64(a.Count)
}
// Ingest is used to update a sample
func (a *AggregateSample) Ingest(v float64) {
a.Count++
a.Sum += v
a.SumSq += (v * v)
if v < a.Min || a.Count == 1 {
a.Min = v
}
if v > a.Max || a.Count == 1 {
a.Max = v
}
a.LastUpdated = time.Now()
}
func (a *AggregateSample) String() string {
if a.Count == 0 {
return "Count: 0"
} else if a.Stddev() == 0 {
return fmt.Sprintf("Count: %d Sum: %0.3f LastUpdated: %s", a.Count, a.Sum, a.LastUpdated)
} else {
return fmt.Sprintf("Count: %d Min: %0.3f Mean: %0.3f Max: %0.3f Stddev: %0.3f Sum: %0.3f LastUpdated: %s",
a.Count, a.Min, a.Mean(), a.Max, a.Stddev(), a.Sum, a.LastUpdated)
}
}
// NewInmemSink is used to construct a new in-memory sink.
// Uses an aggregation interval and maximum retention period.
func NewInmemSink(interval, retain time.Duration) *InmemSink {
i := &InmemSink{
interval: interval,
retain: retain,
maxIntervals: int(retain / interval),
}
i.intervals = make([]*IntervalMetrics, 0, i.maxIntervals)
return i
}
func (i *InmemSink) SetGauge(key []string, val float32) {
k := i.flattenKey(key)
intv := i.getInterval()
intv.Lock()
defer intv.Unlock()
intv.Gauges[k] = val
}
func (i *InmemSink) EmitKey(key []string, val float32) {
k := i.flattenKey(key)
intv := i.getInterval()
intv.Lock()
defer intv.Unlock()
vals := intv.Points[k]
intv.Points[k] = append(vals, val)
}
func (i *InmemSink) IncrCounter(key []string, val float32) {
k := i.flattenKey(key)
intv := i.getInterval()
intv.Lock()
defer intv.Unlock()
agg := intv.Counters[k]
if agg == nil {
agg = &AggregateSample{}
intv.Counters[k] = agg
}
agg.Ingest(float64(val))
}
func (i *InmemSink) AddSample(key []string, val float32) {
k := i.flattenKey(key)
intv := i.getInterval()
intv.Lock()
defer intv.Unlock()
agg := intv.Samples[k]
if agg == nil {
agg = &AggregateSample{}
intv.Samples[k] = agg
}
agg.Ingest(float64(val))
}
// Data is used to retrieve all the aggregated metrics
// Intervals may be in use, and a read lock should be acquired
func (i *InmemSink) Data() []*IntervalMetrics {
// Get the current interval, forces creation
i.getInterval()
i.intervalLock.RLock()
defer i.intervalLock.RUnlock()
intervals := make([]*IntervalMetrics, len(i.intervals))
copy(intervals, i.intervals)
return intervals
}
func (i *InmemSink) getExistingInterval(intv time.Time) *IntervalMetrics {
i.intervalLock.RLock()
defer i.intervalLock.RUnlock()
n := len(i.intervals)
if n > 0 && i.intervals[n-1].Interval == intv {
return i.intervals[n-1]
}
return nil
}
func (i *InmemSink) createInterval(intv time.Time) *IntervalMetrics {
i.intervalLock.Lock()
defer i.intervalLock.Unlock()
// Check for an existing interval
n := len(i.intervals)
if n > 0 && i.intervals[n-1].Interval == intv {
return i.intervals[n-1]
}
// Add the current interval
current := NewIntervalMetrics(intv)
i.intervals = append(i.intervals, current)
n++
// Truncate the intervals if they are too long
if n >= i.maxIntervals {
copy(i.intervals[0:], i.intervals[n-i.maxIntervals:])
i.intervals = i.intervals[:i.maxIntervals]
}
return current
}
// getInterval returns the current interval to write to
func (i *InmemSink) getInterval() *IntervalMetrics {
intv := time.Now().Truncate(i.interval)
if m := i.getExistingInterval(intv); m != nil {
return m
}
return i.createInterval(intv)
}
// Flattens the key for formatting, removes spaces
func (i *InmemSink) flattenKey(parts []string) string {
joined := strings.Join(parts, ".")
return strings.Replace(joined, " ", "_", -1)
}
package metrics
import (
"bytes"
"fmt"
"io"
"os"
"os/signal"
"sync"
"syscall"
)
// InmemSignal is used to listen for a given signal, and when received,
// to dump the current metrics from the InmemSink to an io.Writer
type InmemSignal struct {
signal syscall.Signal
inm *InmemSink
w io.Writer
sigCh chan os.Signal
stop bool
stopCh chan struct{}
stopLock sync.Mutex
}
// NewInmemSignal creates a new InmemSignal which listens for a given signal,
// and dumps the current metrics out to a writer
func NewInmemSignal(inmem *InmemSink, sig syscall.Signal, w io.Writer) *InmemSignal {
i := &InmemSignal{
signal: sig,
inm: inmem,
w: w,
sigCh: make(chan os.Signal, 1),
stopCh: make(chan struct{}),
}
signal.Notify(i.sigCh, sig)
go i.run()
return i
}
// DefaultInmemSignal returns a new InmemSignal that responds to SIGUSR1
// and writes output to stderr. Windows uses SIGBREAK
func DefaultInmemSignal(inmem *InmemSink) *InmemSignal {
return NewInmemSignal(inmem, DefaultSignal, os.Stderr)
}
// Stop is used to stop the InmemSignal from listening
func (i *InmemSignal) Stop() {
i.stopLock.Lock()
defer i.stopLock.Unlock()
if i.stop {
return
}
i.stop = true
close(i.stopCh)
signal.Stop(i.sigCh)
}
// run is a long running routine that handles signals
func (i *InmemSignal) run() {
for {
select {
case <-i.sigCh:
i.dumpStats()
case <-i.stopCh:
return
}
}
}
// dumpStats is used to dump the data to output writer
func (i *InmemSignal) dumpStats() {
buf := bytes.NewBuffer(nil)
data := i.inm.Data()
// Skip the last period which is still being aggregated
for i := 0; i < len(data)-1; i++ {
intv := data[i]
intv.RLock()
for name, val := range intv.Gauges {
fmt.Fprintf(buf, "[%v][G] '%s': %0.3f\n", intv.Interval, name, val)
}
for name, vals := range intv.Points {
for _, val := range vals {
fmt.Fprintf(buf, "[%v][P] '%s': %0.3f\n", intv.Interval, name, val)
}
}
for name, agg := range intv.Counters {
fmt.Fprintf(buf, "[%v][C] '%s': %s\n", intv.Interval, name, agg)
}
for name, agg := range intv.Samples {
fmt.Fprintf(buf, "[%v][S] '%s': %s\n", intv.Interval, name, agg)
}
intv.RUnlock()
}
// Write out the bytes
i.w.Write(buf.Bytes())
}
package metrics
import (
"runtime"
"time"
)
func (m *Metrics) SetGauge(key []string, val float32) {
if m.HostName != "" && m.EnableHostname {
key = insert(0, m.HostName, key)
}
if m.EnableTypePrefix {
key = insert(0, "gauge", key)
}
if m.ServiceName != "" {
key = insert(0, m.ServiceName, key)
}
m.sink.SetGauge(key, val)
}
func (m *Metrics) EmitKey(key []string, val float32) {
if m.EnableTypePrefix {
key = insert(0, "kv", key)
}
if m.ServiceName != "" {
key = insert(0, m.ServiceName, key)
}
m.sink.EmitKey(key, val)
}
func (m *Metrics) IncrCounter(key []string, val float32) {
if m.EnableTypePrefix {
key = insert(0, "counter", key)
}
if m.ServiceName != "" {
key = insert(0, m.ServiceName, key)
}
m.sink.IncrCounter(key, val)
}
func (m *Metrics) AddSample(key []string, val float32) {
if m.EnableTypePrefix {
key = insert(0, "sample", key)
}
if m.ServiceName != "" {
key = insert(0, m.ServiceName, key)
}
m.sink.AddSample(key, val)
}
func (m *Metrics) MeasureSince(key []string, start time.Time) {
if m.EnableTypePrefix {
key = insert(0, "timer", key)
}
if m.ServiceName != "" {
key = insert(0, m.ServiceName, key)
}
now := time.Now()
elapsed := now.Sub(start)
msec := float32(elapsed.Nanoseconds()) / float32(m.TimerGranularity)
m.sink.AddSample(key, msec)
}
// Periodically collects runtime stats to publish
func (m *Metrics) collectStats() {
for {
time.Sleep(m.ProfileInterval)
m.emitRuntimeStats()
}
}
// Emits various runtime statsitics
func (m *Metrics) emitRuntimeStats() {
// Export number of Goroutines
numRoutines := runtime.NumGoroutine()
m.SetGauge([]string{"runtime", "num_goroutines"}, float32(numRoutines))
// Export memory stats
var stats runtime.MemStats
runtime.ReadMemStats(&stats)
m.SetGauge([]string{"runtime", "alloc_bytes"}, float32(stats.Alloc))
m.SetGauge([]string{"runtime", "sys_bytes"}, float32(stats.Sys))
m.SetGauge([]string{"runtime", "malloc_count"}, float32(stats.Mallocs))
m.SetGauge([]string{"runtime", "free_count"}, float32(stats.Frees))
m.SetGauge([]string{"runtime", "heap_objects"}, float32(stats.HeapObjects))
m.SetGauge([]string{"runtime", "total_gc_pause_ns"}, float32(stats.PauseTotalNs))
m.SetGauge([]string{"runtime", "total_gc_runs"}, float32(stats.NumGC))
// Export info about the last few GC runs
num := stats.NumGC
// Handle wrap around
if num < m.lastNumGC {
m.lastNumGC = 0
}
// Ensure we don't scan more than 256
if num-m.lastNumGC >= 256 {
m.lastNumGC = num - 255
}
for i := m.lastNumGC; i < num; i++ {
pause := stats.PauseNs[i%256]
m.AddSample([]string{"runtime", "gc_pause_ns"}, float32(pause))
}
m.lastNumGC = num
}
// Inserts a string value at an index into the slice
func insert(i int, v string, s []string) []string {
s = append(s, "")
copy(s[i+1:], s[i:])
s[i] = v
return s
}
// +build go1.3
package prometheus
import (
"strings"
"sync"
"time"
"github.com/prometheus/client_golang/prometheus"
)
type PrometheusSink struct {
mu sync.Mutex
gauges map[string]prometheus.Gauge
summaries map[string]prometheus.Summary
counters map[string]prometheus.Counter
}
func NewPrometheusSink() (*PrometheusSink, error) {
return &PrometheusSink{
gauges: make(map[string]prometheus.Gauge),
summaries: make(map[string]prometheus.Summary),
counters: make(map[string]prometheus.Counter),
}, nil
}
func (p *PrometheusSink) flattenKey(parts []string) string {
joined := strings.Join(parts, "_")
joined = strings.Replace(joined, " ", "_", -1)
joined = strings.Replace(joined, ".", "_", -1)
joined = strings.Replace(joined, "-", "_", -1)
return joined
}
func (p *PrometheusSink) SetGauge(parts []string, val float32) {
p.mu.Lock()
defer p.mu.Unlock()
key := p.flattenKey(parts)
g, ok := p.gauges[key]
if !ok {
g = prometheus.NewGauge(prometheus.GaugeOpts{
Name: key,
Help: key,
})
prometheus.MustRegister(g)
p.gauges[key] = g
}
g.Set(float64(val))
}
func (p *PrometheusSink) AddSample(parts []string, val float32) {
p.mu.Lock()
defer p.mu.Unlock()
key := p.flattenKey(parts)
g, ok := p.summaries[key]
if !ok {
g = prometheus.NewSummary(prometheus.SummaryOpts{
Name: key,
Help: key,
MaxAge: 10 * time.Second,
})
prometheus.MustRegister(g)
p.summaries[key] = g
}
g.Observe(float64(val))
}
// EmitKey is not implemented. Prometheus doesn’t offer a type for which an
// arbitrary number of values is retained, as Prometheus works with a pull
// model, rather than a push model.
func (p *PrometheusSink) EmitKey(key []string, val float32) {
}
func (p *PrometheusSink) IncrCounter(parts []string, val float32) {
p.mu.Lock()
defer p.mu.Unlock()
key := p.flattenKey(parts)
g, ok := p.counters[key]
if !ok {
g = prometheus.NewCounter(prometheus.CounterOpts{
Name: key,
Help: key,
})
prometheus.MustRegister(g)
p.counters[key] = g
}
g.Add(float64(val))
}
package metrics
// The MetricSink interface is used to transmit metrics information
// to an external system
type MetricSink interface {
// A Gauge should retain the last value it is set to
SetGauge(key []string, val float32)
// Should emit a Key/Value pair for each call
EmitKey(key []string, val float32)
// Counters should accumulate values
IncrCounter(key []string, val float32)
// Samples are for timing information, where quantiles are used
AddSample(key []string, val float32)
}
// BlackholeSink is used to just blackhole messages
type BlackholeSink struct{}
func (*BlackholeSink) SetGauge(key []string, val float32) {}
func (*BlackholeSink) EmitKey(key []string, val float32) {}
func (*BlackholeSink) IncrCounter(key []string, val float32) {}
func (*BlackholeSink) AddSample(key []string, val float32) {}
// FanoutSink is used to sink to fanout values to multiple sinks
type FanoutSink []MetricSink
func (fh FanoutSink) SetGauge(key []string, val float32) {
for _, s := range fh {
s.SetGauge(key, val)
}
}
func (fh FanoutSink) EmitKey(key []string, val float32) {
for _, s := range fh {
s.EmitKey(key, val)
}
}
func (fh FanoutSink) IncrCounter(key []string, val float32) {
for _, s := range fh {
s.IncrCounter(key, val)
}
}
func (fh FanoutSink) AddSample(key []string, val float32) {
for _, s := range fh {
s.AddSample(key, val)
}
}
package metrics
import (
"os"
"time"
)
// Config is used to configure metrics settings
type Config struct {
ServiceName string // Prefixed with keys to seperate services
HostName string // Hostname to use. If not provided and EnableHostname, it will be os.Hostname
EnableHostname bool // Enable prefixing gauge values with hostname
EnableRuntimeMetrics bool // Enables profiling of runtime metrics (GC, Goroutines, Memory)
EnableTypePrefix bool // Prefixes key with a type ("counter", "gauge", "timer")
TimerGranularity time.Duration // Granularity of timers.
ProfileInterval time.Duration // Interval to profile runtime metrics
}
// Metrics represents an instance of a metrics sink that can
// be used to emit
type Metrics struct {
Config
lastNumGC uint32
sink MetricSink
}
// Shared global metrics instance
var globalMetrics *Metrics
func init() {
// Initialize to a blackhole sink to avoid errors
globalMetrics = &Metrics{sink: &BlackholeSink{}}
}
// DefaultConfig provides a sane default configuration
func DefaultConfig(serviceName string) *Config {
c := &Config{
ServiceName: serviceName, // Use client provided service
HostName: "",
EnableHostname: true, // Enable hostname prefix
EnableRuntimeMetrics: true, // Enable runtime profiling
EnableTypePrefix: false, // Disable type prefix
TimerGranularity: time.Millisecond, // Timers are in milliseconds
ProfileInterval: time.Second, // Poll runtime every second
}
// Try to get the hostname
name, _ := os.Hostname()
c.HostName = name
return c
}
// New is used to create a new instance of Metrics
func New(conf *Config, sink MetricSink) (*Metrics, error) {
met := &Metrics{}
met.Config = *conf
met.sink = sink
// Start the runtime collector
if conf.EnableRuntimeMetrics {
go met.collectStats()
}
return met, nil
}
// NewGlobal is the same as New, but it assigns the metrics object to be
// used globally as well as returning it.
func NewGlobal(conf *Config, sink MetricSink) (*Metrics, error) {
metrics, err := New(conf, sink)
if err == nil {
globalMetrics = metrics
}
return metrics, err
}
// Proxy all the methods to the globalMetrics instance
func SetGauge(key []string, val float32) {
globalMetrics.SetGauge(key, val)
}
func EmitKey(key []string, val float32) {
globalMetrics.EmitKey(key, val)
}
func IncrCounter(key []string, val float32) {
globalMetrics.IncrCounter(key, val)
}
func AddSample(key []string, val float32) {
globalMetrics.AddSample(key, val)
}
func MeasureSince(key []string, start time.Time) {
globalMetrics.MeasureSince(key, start)
}
package metrics
import (
"bytes"
"fmt"
"log"
"net"
"strings"
"time"
)
const (
// statsdMaxLen is the maximum size of a packet
// to send to statsd
statsdMaxLen = 1400
)
// StatsdSink provides a MetricSink that can be used
// with a statsite or statsd metrics server. It uses
// only UDP packets, while StatsiteSink uses TCP.
type StatsdSink struct {
addr string
metricQueue chan string
}
// NewStatsdSink is used to create a new StatsdSink
func NewStatsdSink(addr string) (*StatsdSink, error) {
s := &StatsdSink{
addr: addr,
metricQueue: make(chan string, 4096),
}
go s.flushMetrics()
return s, nil
}
// Close is used to stop flushing to statsd
func (s *StatsdSink) Shutdown() {
close(s.metricQueue)
}
func (s *StatsdSink) SetGauge(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|g\n", flatKey, val))
}
func (s *StatsdSink) EmitKey(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|kv\n", flatKey, val))
}
func (s *StatsdSink) IncrCounter(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|c\n", flatKey, val))
}
func (s *StatsdSink) AddSample(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|ms\n", flatKey, val))
}
// Flattens the key for formatting, removes spaces
func (s *StatsdSink) flattenKey(parts []string) string {
joined := strings.Join(parts, ".")
return strings.Map(func(r rune) rune {
switch r {
case ':':
fallthrough
case ' ':
return '_'
default:
return r
}
}, joined)
}
// Does a non-blocking push to the metrics queue
func (s *StatsdSink) pushMetric(m string) {
select {
case s.metricQueue <- m:
default:
}
}
// Flushes metrics
func (s *StatsdSink) flushMetrics() {
var sock net.Conn
var err error
var wait <-chan time.Time
ticker := time.NewTicker(flushInterval)
defer ticker.Stop()
CONNECT:
// Create a buffer
buf := bytes.NewBuffer(nil)
// Attempt to connect
sock, err = net.Dial("udp", s.addr)
if err != nil {
log.Printf("[ERR] Error connecting to statsd! Err: %s", err)
goto WAIT
}
for {
select {
case metric, ok := <-s.metricQueue:
// Get a metric from the queue
if !ok {
goto QUIT
}
// Check if this would overflow the packet size
if len(metric)+buf.Len() > statsdMaxLen {
_, err := sock.Write(buf.Bytes())
buf.Reset()
if err != nil {
log.Printf("[ERR] Error writing to statsd! Err: %s", err)
goto WAIT
}
}
// Append to the buffer
buf.WriteString(metric)
case <-ticker.C:
if buf.Len() == 0 {
continue
}
_, err := sock.Write(buf.Bytes())
buf.Reset()
if err != nil {
log.Printf("[ERR] Error flushing to statsd! Err: %s", err)
goto WAIT
}
}
}
WAIT:
// Wait for a while
wait = time.After(time.Duration(5) * time.Second)
for {
select {
// Dequeue the messages to avoid backlog
case _, ok := <-s.metricQueue:
if !ok {
goto QUIT
}
case <-wait:
goto CONNECT
}
}
QUIT:
s.metricQueue = nil
}
package metrics
import (
"bufio"
"fmt"
"log"
"net"
"strings"
"time"
)
const (
// We force flush the statsite metrics after this period of
// inactivity. Prevents stats from getting stuck in a buffer
// forever.
flushInterval = 100 * time.Millisecond
)
// StatsiteSink provides a MetricSink that can be used with a
// statsite metrics server
type StatsiteSink struct {
addr string
metricQueue chan string
}
// NewStatsiteSink is used to create a new StatsiteSink
func NewStatsiteSink(addr string) (*StatsiteSink, error) {
s := &StatsiteSink{
addr: addr,
metricQueue: make(chan string, 4096),
}
go s.flushMetrics()
return s, nil
}
// Close is used to stop flushing to statsite
func (s *StatsiteSink) Shutdown() {
close(s.metricQueue)
}
func (s *StatsiteSink) SetGauge(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|g\n", flatKey, val))
}
func (s *StatsiteSink) EmitKey(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|kv\n", flatKey, val))
}
func (s *StatsiteSink) IncrCounter(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|c\n", flatKey, val))
}
func (s *StatsiteSink) AddSample(key []string, val float32) {
flatKey := s.flattenKey(key)
s.pushMetric(fmt.Sprintf("%s:%f|ms\n", flatKey, val))
}
// Flattens the key for formatting, removes spaces
func (s *StatsiteSink) flattenKey(parts []string) string {
joined := strings.Join(parts, ".")
return strings.Map(func(r rune) rune {
switch r {
case ':':
fallthrough
case ' ':
return '_'
default:
return r
}
}, joined)
}
// Does a non-blocking push to the metrics queue
func (s *StatsiteSink) pushMetric(m string) {
select {
case s.metricQueue <- m:
default:
}
}
// Flushes metrics
func (s *StatsiteSink) flushMetrics() {
var sock net.Conn
var err error
var wait <-chan time.Time
var buffered *bufio.Writer
ticker := time.NewTicker(flushInterval)
defer ticker.Stop()
CONNECT:
// Attempt to connect
sock, err = net.Dial("tcp", s.addr)
if err != nil {
log.Printf("[ERR] Error connecting to statsite! Err: %s", err)
goto WAIT
}
// Create a buffered writer
buffered = bufio.NewWriter(sock)
for {
select {
case metric, ok := <-s.metricQueue:
// Get a metric from the queue
if !ok {
goto QUIT
}
// Try to send to statsite
_, err := buffered.Write([]byte(metric))
if err != nil {
log.Printf("[ERR] Error writing to statsite! Err: %s", err)
goto WAIT
}
case <-ticker.C:
if err := buffered.Flush(); err != nil {
log.Printf("[ERR] Error flushing to statsite! Err: %s", err)
goto WAIT
}
}
}
WAIT:
// Wait for a while
wait = time.After(time.Duration(5) * time.Second)
for {
select {
// Dequeue the messages to avoid backlog
case _, ok := <-s.metricQueue:
if !ok {
goto QUIT
}
case <-wait:
goto CONNECT
}
}
QUIT:
s.metricQueue = nil
}
Copyright (c) 2012, 2013 Ugorji Nwoke.
All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name of the author nor the names of its contributors may be used
to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Copyright (c) 2012, 2013 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a BSD-style license found in the LICENSE file.
/*
High Performance, Feature-Rich Idiomatic Go encoding library for msgpack and binc .
Supported Serialization formats are:
- msgpack: [https://github.com/msgpack/msgpack]
- binc: [http://github.com/ugorji/binc]
To install:
go get github.com/ugorji/go/codec
The idiomatic Go support is as seen in other encoding packages in
the standard library (ie json, xml, gob, etc).
Rich Feature Set includes:
- Simple but extremely powerful and feature-rich API
- Very High Performance.
Our extensive benchmarks show us outperforming Gob, Json and Bson by 2-4X.
This was achieved by taking extreme care on:
- managing allocation
- function frame size (important due to Go's use of split stacks),
- reflection use (and by-passing reflection for common types)
- recursion implications
- zero-copy mode (encoding/decoding to byte slice without using temp buffers)
- Correct.
Care was taken to precisely handle corner cases like:
overflows, nil maps and slices, nil value in stream, etc.
- Efficient zero-copying into temporary byte buffers
when encoding into or decoding from a byte slice.
- Standard field renaming via tags
- Encoding from any value
(struct, slice, map, primitives, pointers, interface{}, etc)
- Decoding into pointer to any non-nil typed value
(struct, slice, map, int, float32, bool, string, reflect.Value, etc)
- Supports extension functions to handle the encode/decode of custom types
- Support Go 1.2 encoding.BinaryMarshaler/BinaryUnmarshaler
- Schema-less decoding
(decode into a pointer to a nil interface{} as opposed to a typed non-nil value).
Includes Options to configure what specific map or slice type to use
when decoding an encoded list or map into a nil interface{}
- Provides a RPC Server and Client Codec for net/rpc communication protocol.
- Msgpack Specific:
- Provides extension functions to handle spec-defined extensions (binary, timestamp)
- Options to resolve ambiguities in handling raw bytes (as string or []byte)
during schema-less decoding (decoding into a nil interface{})
- RPC Server/Client Codec for msgpack-rpc protocol defined at:
https://github.com/msgpack-rpc/msgpack-rpc/blob/master/spec.md
- Fast Paths for some container types:
For some container types, we circumvent reflection and its associated overhead
and allocation costs, and encode/decode directly. These types are:
[]interface{}
[]int
[]string
map[interface{}]interface{}
map[int]interface{}
map[string]interface{}
Extension Support
Users can register a function to handle the encoding or decoding of
their custom types.
There are no restrictions on what the custom type can be. Some examples:
type BisSet []int
type BitSet64 uint64
type UUID string
type MyStructWithUnexportedFields struct { a int; b bool; c []int; }
type GifImage struct { ... }
As an illustration, MyStructWithUnexportedFields would normally be
encoded as an empty map because it has no exported fields, while UUID
would be encoded as a string. However, with extension support, you can
encode any of these however you like.
RPC
RPC Client and Server Codecs are implemented, so the codecs can be used
with the standard net/rpc package.
Usage
Typical usage model:
// create and configure Handle
var (
bh codec.BincHandle
mh codec.MsgpackHandle
)
mh.MapType = reflect.TypeOf(map[string]interface{}(nil))
// configure extensions
// e.g. for msgpack, define functions and enable Time support for tag 1
// mh.AddExt(reflect.TypeOf(time.Time{}), 1, myMsgpackTimeEncodeExtFn, myMsgpackTimeDecodeExtFn)
// create and use decoder/encoder
var (
r io.Reader
w io.Writer
b []byte
h = &bh // or mh to use msgpack
)
dec = codec.NewDecoder(r, h)
dec = codec.NewDecoderBytes(b, h)
err = dec.Decode(&v)
enc = codec.NewEncoder(w, h)
enc = codec.NewEncoderBytes(&b, h)
err = enc.Encode(v)
//RPC Server
go func() {
for {
conn, err := listener.Accept()
rpcCodec := codec.GoRpc.ServerCodec(conn, h)
//OR rpcCodec := codec.MsgpackSpecRpc.ServerCodec(conn, h)
rpc.ServeCodec(rpcCodec)
}
}()
//RPC Communication (client side)
conn, err = net.Dial("tcp", "localhost:5555")
rpcCodec := codec.GoRpc.ClientCodec(conn, h)
//OR rpcCodec := codec.MsgpackSpecRpc.ClientCodec(conn, h)
client := rpc.NewClientWithCodec(rpcCodec)
Representative Benchmark Results
Run the benchmark suite using:
go test -bi -bench=. -benchmem
To run full benchmark suite (including against vmsgpack and bson),
see notes in ext_dep_test.go
*/
package codec
# Codec
High Performance and Feature-Rich Idiomatic Go Library providing
encode/decode support for different serialization formats.
Supported Serialization formats are:
- msgpack: [https://github.com/msgpack/msgpack]
- binc: [http://github.com/ugorji/binc]
To install:
go get github.com/ugorji/go/codec
Online documentation: [http://godoc.org/github.com/ugorji/go/codec]
The idiomatic Go support is as seen in other encoding packages in
the standard library (ie json, xml, gob, etc).
Rich Feature Set includes:
- Simple but extremely powerful and feature-rich API
- Very High Performance.
Our extensive benchmarks show us outperforming Gob, Json and Bson by 2-4X.
This was achieved by taking extreme care on:
- managing allocation
- function frame size (important due to Go's use of split stacks),
- reflection use (and by-passing reflection for common types)
- recursion implications
- zero-copy mode (encoding/decoding to byte slice without using temp buffers)
- Correct.
Care was taken to precisely handle corner cases like:
overflows, nil maps and slices, nil value in stream, etc.
- Efficient zero-copying into temporary byte buffers
when encoding into or decoding from a byte slice.
- Standard field renaming via tags
- Encoding from any value
(struct, slice, map, primitives, pointers, interface{}, etc)
- Decoding into pointer to any non-nil typed value
(struct, slice, map, int, float32, bool, string, reflect.Value, etc)
- Supports extension functions to handle the encode/decode of custom types
- Support Go 1.2 encoding.BinaryMarshaler/BinaryUnmarshaler
- Schema-less decoding
(decode into a pointer to a nil interface{} as opposed to a typed non-nil value).
Includes Options to configure what specific map or slice type to use
when decoding an encoded list or map into a nil interface{}
- Provides a RPC Server and Client Codec for net/rpc communication protocol.
- Msgpack Specific:
- Provides extension functions to handle spec-defined extensions (binary, timestamp)
- Options to resolve ambiguities in handling raw bytes (as string or []byte)
during schema-less decoding (decoding into a nil interface{})
- RPC Server/Client Codec for msgpack-rpc protocol defined at:
https://github.com/msgpack-rpc/msgpack-rpc/blob/master/spec.md
- Fast Paths for some container types:
For some container types, we circumvent reflection and its associated overhead
and allocation costs, and encode/decode directly. These types are:
[]interface{}
[]int
[]string
map[interface{}]interface{}
map[int]interface{}
map[string]interface{}
## Extension Support
Users can register a function to handle the encoding or decoding of
their custom types.
There are no restrictions on what the custom type can be. Some examples:
type BisSet []int
type BitSet64 uint64
type UUID string
type MyStructWithUnexportedFields struct { a int; b bool; c []int; }
type GifImage struct { ... }
As an illustration, MyStructWithUnexportedFields would normally be
encoded as an empty map because it has no exported fields, while UUID
would be encoded as a string. However, with extension support, you can
encode any of these however you like.
## RPC
RPC Client and Server Codecs are implemented, so the codecs can be used
with the standard net/rpc package.
## Usage
Typical usage model:
// create and configure Handle
var (
bh codec.BincHandle
mh codec.MsgpackHandle
)
mh.MapType = reflect.TypeOf(map[string]interface{}(nil))
// configure extensions
// e.g. for msgpack, define functions and enable Time support for tag 1
// mh.AddExt(reflect.TypeOf(time.Time{}), 1, myMsgpackTimeEncodeExtFn, myMsgpackTimeDecodeExtFn)
// create and use decoder/encoder
var (
r io.Reader
w io.Writer
b []byte
h = &bh // or mh to use msgpack
)
dec = codec.NewDecoder(r, h)
dec = codec.NewDecoderBytes(b, h)
err = dec.Decode(&v)
enc = codec.NewEncoder(w, h)
enc = codec.NewEncoderBytes(&b, h)
err = enc.Encode(v)
//RPC Server
go func() {
for {
conn, err := listener.Accept()
rpcCodec := codec.GoRpc.ServerCodec(conn, h)
//OR rpcCodec := codec.MsgpackSpecRpc.ServerCodec(conn, h)
rpc.ServeCodec(rpcCodec)
}
}()
//RPC Communication (client side)
conn, err = net.Dial("tcp", "localhost:5555")
rpcCodec := codec.GoRpc.ClientCodec(conn, h)
//OR rpcCodec := codec.MsgpackSpecRpc.ClientCodec(conn, h)
client := rpc.NewClientWithCodec(rpcCodec)
## Representative Benchmark Results
A sample run of benchmark using "go test -bi -bench=. -benchmem":
/proc/cpuinfo: Intel(R) Core(TM) i7-2630QM CPU @ 2.00GHz (HT)
..............................................
BENCHMARK INIT: 2013-10-16 11:02:50.345970786 -0400 EDT
To run full benchmark comparing encodings (MsgPack, Binc, JSON, GOB, etc), use: "go test -bench=."
Benchmark:
Struct recursive Depth: 1
ApproxDeepSize Of benchmark Struct: 4694 bytes
Benchmark One-Pass Run:
v-msgpack: len: 1600 bytes
bson: len: 3025 bytes
msgpack: len: 1560 bytes
binc: len: 1187 bytes
gob: len: 1972 bytes
json: len: 2538 bytes
..............................................
PASS
Benchmark__Msgpack____Encode 50000 54359 ns/op 14953 B/op 83 allocs/op
Benchmark__Msgpack____Decode 10000 106531 ns/op 14990 B/op 410 allocs/op
Benchmark__Binc_NoSym_Encode 50000 53956 ns/op 14966 B/op 83 allocs/op
Benchmark__Binc_NoSym_Decode 10000 103751 ns/op 14529 B/op 386 allocs/op
Benchmark__Binc_Sym___Encode 50000 65961 ns/op 17130 B/op 88 allocs/op
Benchmark__Binc_Sym___Decode 10000 106310 ns/op 15857 B/op 287 allocs/op
Benchmark__Gob________Encode 10000 135944 ns/op 21189 B/op 237 allocs/op
Benchmark__Gob________Decode 5000 405390 ns/op 83460 B/op 1841 allocs/op
Benchmark__Json_______Encode 20000 79412 ns/op 13874 B/op 102 allocs/op
Benchmark__Json_______Decode 10000 247979 ns/op 14202 B/op 493 allocs/op
Benchmark__Bson_______Encode 10000 121762 ns/op 27814 B/op 514 allocs/op
Benchmark__Bson_______Decode 10000 162126 ns/op 16514 B/op 789 allocs/op
Benchmark__VMsgpack___Encode 50000 69155 ns/op 12370 B/op 344 allocs/op
Benchmark__VMsgpack___Decode 10000 151609 ns/op 20307 B/op 571 allocs/op
ok ugorji.net/codec 30.827s
To run full benchmark suite (including against vmsgpack and bson),
see notes in ext\_dep\_test.go
// Copyright (c) 2012, 2013 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a BSD-style license found in the LICENSE file.
package codec
// All non-std package dependencies live in this file,
// so porting to different environment is easy (just update functions).
import (
"errors"
"fmt"
"math"
"reflect"
)
var (
raisePanicAfterRecover = false
debugging = true
)
func panicValToErr(panicVal interface{}, err *error) {
switch xerr := panicVal.(type) {
case error:
*err = xerr
case string:
*err = errors.New(xerr)
default:
*err = fmt.Errorf("%v", panicVal)
}
if raisePanicAfterRecover {
panic(panicVal)
}
return
}
func isEmptyValueDeref(v reflect.Value, deref bool) bool {
switch v.Kind() {
case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
return v.Len() == 0
case reflect.Bool:
return !v.Bool()
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
return v.Int() == 0
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
return v.Uint() == 0
case reflect.Float32, reflect.Float64:
return v.Float() == 0
case reflect.Interface, reflect.Ptr:
if deref {
if v.IsNil() {
return true
}
return isEmptyValueDeref(v.Elem(), deref)
} else {
return v.IsNil()
}
case reflect.Struct:
// return true if all fields are empty. else return false.
// we cannot use equality check, because some fields may be maps/slices/etc
// and consequently the structs are not comparable.
// return v.Interface() == reflect.Zero(v.Type()).Interface()
for i, n := 0, v.NumField(); i < n; i++ {
if !isEmptyValueDeref(v.Field(i), deref) {
return false
}
}
return true
}
return false
}
func isEmptyValue(v reflect.Value) bool {
return isEmptyValueDeref(v, true)
}
func debugf(format string, args ...interface{}) {
if debugging {
if len(format) == 0 || format[len(format)-1] != '\n' {
format = format + "\n"
}
fmt.Printf(format, args...)
}
}
func pruneSignExt(v []byte, pos bool) (n int) {
if len(v) < 2 {
} else if pos && v[0] == 0 {
for ; v[n] == 0 && n+1 < len(v) && (v[n+1]&(1<<7) == 0); n++ {
}
} else if !pos && v[0] == 0xff {
for ; v[n] == 0xff && n+1 < len(v) && (v[n+1]&(1<<7) != 0); n++ {
}
}
return
}
func implementsIntf(typ, iTyp reflect.Type) (success bool, indir int8) {
if typ == nil {
return
}
rt := typ
// The type might be a pointer and we need to keep
// dereferencing to the base type until we find an implementation.
for {
if rt.Implements(iTyp) {
return true, indir
}
if p := rt; p.Kind() == reflect.Ptr {
indir++
if indir >= math.MaxInt8 { // insane number of indirections
return false, 0
}
rt = p.Elem()
continue
}
break
}
// No luck yet, but if this is a base type (non-pointer), the pointer might satisfy.
if typ.Kind() != reflect.Ptr {
// Not a pointer, but does the pointer work?
if reflect.PtrTo(typ).Implements(iTyp) {
return true, -1
}
}
return false, 0
}
#!/usr/bin/env python
# This will create golden files in a directory passed to it.
# A Test calls this internally to create the golden files
# So it can process them (so we don't have to checkin the files).
import msgpack, msgpackrpc, sys, os, threading
def get_test_data_list():
# get list with all primitive types, and a combo type
l0 = [
-8,
-1616,
-32323232,
-6464646464646464,
192,
1616,
32323232,
6464646464646464,
192,
-3232.0,
-6464646464.0,
3232.0,
6464646464.0,
False,
True,
None,
"someday",
"",
"bytestring",
1328176922000002000,
-2206187877999998000,
0,
-6795364578871345152
]
l1 = [
{ "true": True,
"false": False },
{ "true": "True",
"false": False,
"uint16(1616)": 1616 },
{ "list": [1616, 32323232, True, -3232.0, {"TRUE":True, "FALSE":False}, [True, False] ],
"int32":32323232, "bool": True,
"LONG STRING": "123456789012345678901234567890123456789012345678901234567890",
"SHORT STRING": "1234567890" },
{ True: "true", 8: False, "false": 0 }
]
l = []
l.extend(l0)
l.append(l0)
l.extend(l1)
return l
def build_test_data(destdir):
l = get_test_data_list()
for i in range(len(l)):
packer = msgpack.Packer()
serialized = packer.pack(l[i])
f = open(os.path.join(destdir, str(i) + '.golden'), 'wb')
f.write(serialized)
f.close()
def doRpcServer(port, stopTimeSec):
class EchoHandler(object):
def Echo123(self, msg1, msg2, msg3):
return ("1:%s 2:%s 3:%s" % (msg1, msg2, msg3))
def EchoStruct(self, msg):
return ("%s" % msg)
addr = msgpackrpc.Address('localhost', port)
server = msgpackrpc.Server(EchoHandler())
server.listen(addr)
# run thread to stop it after stopTimeSec seconds if > 0
if stopTimeSec > 0:
def myStopRpcServer():
server.stop()
t = threading.Timer(stopTimeSec, myStopRpcServer)
t.start()
server.start()
def doRpcClientToPythonSvc(port):
address = msgpackrpc.Address('localhost', port)
client = msgpackrpc.Client(address, unpack_encoding='utf-8')
print client.call("Echo123", "A1", "B2", "C3")
print client.call("EchoStruct", {"A" :"Aa", "B":"Bb", "C":"Cc"})
def doRpcClientToGoSvc(port):
# print ">>>> port: ", port, " <<<<<"
address = msgpackrpc.Address('localhost', port)
client = msgpackrpc.Client(address, unpack_encoding='utf-8')
print client.call("TestRpcInt.Echo123", ["A1", "B2", "C3"])
print client.call("TestRpcInt.EchoStruct", {"A" :"Aa", "B":"Bb", "C":"Cc"})
def doMain(args):
if len(args) == 2 and args[0] == "testdata":
build_test_data(args[1])
elif len(args) == 3 and args[0] == "rpc-server":
doRpcServer(int(args[1]), int(args[2]))
elif len(args) == 2 and args[0] == "rpc-client-python-service":
doRpcClientToPythonSvc(int(args[1]))
elif len(args) == 2 and args[0] == "rpc-client-go-service":
doRpcClientToGoSvc(int(args[1]))
else:
print("Usage: msgpack_test.py " +
"[testdata|rpc-server|rpc-client-python-service|rpc-client-go-service] ...")
if __name__ == "__main__":
doMain(sys.argv[1:])
// Copyright (c) 2012, 2013 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a BSD-style license found in the LICENSE file.
package codec
import (
"bufio"
"io"
"net/rpc"
"sync"
)
// Rpc provides a rpc Server or Client Codec for rpc communication.
type Rpc interface {
ServerCodec(conn io.ReadWriteCloser, h Handle) rpc.ServerCodec
ClientCodec(conn io.ReadWriteCloser, h Handle) rpc.ClientCodec
}
// RpcCodecBuffered allows access to the underlying bufio.Reader/Writer
// used by the rpc connection. It accomodates use-cases where the connection
// should be used by rpc and non-rpc functions, e.g. streaming a file after
// sending an rpc response.
type RpcCodecBuffered interface {
BufferedReader() *bufio.Reader
BufferedWriter() *bufio.Writer
}
// -------------------------------------
// rpcCodec defines the struct members and common methods.
type rpcCodec struct {
rwc io.ReadWriteCloser
dec *Decoder
enc *Encoder
bw *bufio.Writer
br *bufio.Reader
mu sync.Mutex
cls bool
}
func newRPCCodec(conn io.ReadWriteCloser, h Handle) rpcCodec {
bw := bufio.NewWriter(conn)
br := bufio.NewReader(conn)
return rpcCodec{
rwc: conn,
bw: bw,
br: br,
enc: NewEncoder(bw, h),
dec: NewDecoder(br, h),
}
}
func (c *rpcCodec) BufferedReader() *bufio.Reader {
return c.br
}
func (c *rpcCodec) BufferedWriter() *bufio.Writer {
return c.bw
}
func (c *rpcCodec) write(obj1, obj2 interface{}, writeObj2, doFlush bool) (err error) {
if c.cls {
return io.EOF
}
if err = c.enc.Encode(obj1); err != nil {
return
}
if writeObj2 {
if err = c.enc.Encode(obj2); err != nil {
return
}
}
if doFlush && c.bw != nil {
return c.bw.Flush()
}
return
}
func (c *rpcCodec) read(obj interface{}) (err error) {
if c.cls {
return io.EOF
}
//If nil is passed in, we should still attempt to read content to nowhere.
if obj == nil {
var obj2 interface{}
return c.dec.Decode(&obj2)
}
return c.dec.Decode(obj)
}
func (c *rpcCodec) Close() error {
if c.cls {
return io.EOF
}
c.cls = true
return c.rwc.Close()
}
func (c *rpcCodec) ReadResponseBody(body interface{}) error {
return c.read(body)
}
// -------------------------------------
type goRpcCodec struct {
rpcCodec
}
func (c *goRpcCodec) WriteRequest(r *rpc.Request, body interface{}) error {
// Must protect for concurrent access as per API
c.mu.Lock()
defer c.mu.Unlock()
return c.write(r, body, true, true)
}
func (c *goRpcCodec) WriteResponse(r *rpc.Response, body interface{}) error {
c.mu.Lock()
defer c.mu.Unlock()
return c.write(r, body, true, true)
}
func (c *goRpcCodec) ReadResponseHeader(r *rpc.Response) error {
return c.read(r)
}
func (c *goRpcCodec) ReadRequestHeader(r *rpc.Request) error {
return c.read(r)
}
func (c *goRpcCodec) ReadRequestBody(body interface{}) error {
return c.read(body)
}
// -------------------------------------
// goRpc is the implementation of Rpc that uses the communication protocol
// as defined in net/rpc package.
type goRpc struct{}
// GoRpc implements Rpc using the communication protocol defined in net/rpc package.
// Its methods (ServerCodec and ClientCodec) return values that implement RpcCodecBuffered.
var GoRpc goRpc
func (x goRpc) ServerCodec(conn io.ReadWriteCloser, h Handle) rpc.ServerCodec {
return &goRpcCodec{newRPCCodec(conn, h)}
}
func (x goRpc) ClientCodec(conn io.ReadWriteCloser, h Handle) rpc.ClientCodec {
return &goRpcCodec{newRPCCodec(conn, h)}
}
var _ RpcCodecBuffered = (*rpcCodec)(nil) // ensure *rpcCodec implements RpcCodecBuffered
// Copyright (c) 2012, 2013 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a BSD-style license found in the LICENSE file.
package codec
import (
"time"
)
var (
timeDigits = [...]byte{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9'}
)
// EncodeTime encodes a time.Time as a []byte, including
// information on the instant in time and UTC offset.
//
// Format Description
//
// A timestamp is composed of 3 components:
//
// - secs: signed integer representing seconds since unix epoch
// - nsces: unsigned integer representing fractional seconds as a
// nanosecond offset within secs, in the range 0 <= nsecs < 1e9
// - tz: signed integer representing timezone offset in minutes east of UTC,
// and a dst (daylight savings time) flag
//
// When encoding a timestamp, the first byte is the descriptor, which
// defines which components are encoded and how many bytes are used to
// encode secs and nsecs components. *If secs/nsecs is 0 or tz is UTC, it
// is not encoded in the byte array explicitly*.
//
// Descriptor 8 bits are of the form `A B C DDD EE`:
// A: Is secs component encoded? 1 = true
// B: Is nsecs component encoded? 1 = true
// C: Is tz component encoded? 1 = true
// DDD: Number of extra bytes for secs (range 0-7).
// If A = 1, secs encoded in DDD+1 bytes.
// If A = 0, secs is not encoded, and is assumed to be 0.
// If A = 1, then we need at least 1 byte to encode secs.
// DDD says the number of extra bytes beyond that 1.
// E.g. if DDD=0, then secs is represented in 1 byte.
// if DDD=2, then secs is represented in 3 bytes.
// EE: Number of extra bytes for nsecs (range 0-3).
// If B = 1, nsecs encoded in EE+1 bytes (similar to secs/DDD above)
//
// Following the descriptor bytes, subsequent bytes are:
//
// secs component encoded in `DDD + 1` bytes (if A == 1)
// nsecs component encoded in `EE + 1` bytes (if B == 1)
// tz component encoded in 2 bytes (if C == 1)
//
// secs and nsecs components are integers encoded in a BigEndian
// 2-complement encoding format.
//
// tz component is encoded as 2 bytes (16 bits). Most significant bit 15 to
// Least significant bit 0 are described below:
//
// Timezone offset has a range of -12:00 to +14:00 (ie -720 to +840 minutes).
// Bit 15 = have\_dst: set to 1 if we set the dst flag.
// Bit 14 = dst\_on: set to 1 if dst is in effect at the time, or 0 if not.
// Bits 13..0 = timezone offset in minutes. It is a signed integer in Big Endian format.
//
func encodeTime(t time.Time) []byte {
//t := rv.Interface().(time.Time)
tsecs, tnsecs := t.Unix(), t.Nanosecond()
var (
bd byte
btmp [8]byte
bs [16]byte
i int = 1
)
l := t.Location()
if l == time.UTC {
l = nil
}
if tsecs != 0 {
bd = bd | 0x80
bigen.PutUint64(btmp[:], uint64(tsecs))
f := pruneSignExt(btmp[:], tsecs >= 0)
bd = bd | (byte(7-f) << 2)
copy(bs[i:], btmp[f:])
i = i + (8 - f)
}
if tnsecs != 0 {
bd = bd | 0x40
bigen.PutUint32(btmp[:4], uint32(tnsecs))
f := pruneSignExt(btmp[:4], true)
bd = bd | byte(3-f)
copy(bs[i:], btmp[f:4])
i = i + (4 - f)
}
if l != nil {
bd = bd | 0x20
// Note that Go Libs do not give access to dst flag.
_, zoneOffset := t.Zone()
//zoneName, zoneOffset := t.Zone()
zoneOffset /= 60
z := uint16(zoneOffset)
bigen.PutUint16(btmp[:2], z)
// clear dst flags
bs[i] = btmp[0] & 0x3f
bs[i+1] = btmp[1]
i = i + 2
}
bs[0] = bd
return bs[0:i]
}
// DecodeTime decodes a []byte into a time.Time.
func decodeTime(bs []byte) (tt time.Time, err error) {
bd := bs[0]
var (
tsec int64
tnsec uint32
tz uint16
i byte = 1
i2 byte
n byte
)
if bd&(1<<7) != 0 {
var btmp [8]byte
n = ((bd >> 2) & 0x7) + 1
i2 = i + n
copy(btmp[8-n:], bs[i:i2])
//if first bit of bs[i] is set, then fill btmp[0..8-n] with 0xff (ie sign extend it)
if bs[i]&(1<<7) != 0 {
copy(btmp[0:8-n], bsAll0xff)
//for j,k := byte(0), 8-n; j < k; j++ { btmp[j] = 0xff }
}
i = i2
tsec = int64(bigen.Uint64(btmp[:]))
}
if bd&(1<<6) != 0 {
var btmp [4]byte
n = (bd & 0x3) + 1
i2 = i + n
copy(btmp[4-n:], bs[i:i2])
i = i2
tnsec = bigen.Uint32(btmp[:])
}
if bd&(1<<5) == 0 {
tt = time.Unix(tsec, int64(tnsec)).UTC()
return
}
// In stdlib time.Parse, when a date is parsed without a zone name, it uses "" as zone name.
// However, we need name here, so it can be shown when time is printed.
// Zone name is in form: UTC-08:00.
// Note that Go Libs do not give access to dst flag, so we ignore dst bits
i2 = i + 2
tz = bigen.Uint16(bs[i:i2])
i = i2
// sign extend sign bit into top 2 MSB (which were dst bits):
if tz&(1<<13) == 0 { // positive
tz = tz & 0x3fff //clear 2 MSBs: dst bits
} else { // negative
tz = tz | 0xc000 //set 2 MSBs: dst bits
//tzname[3] = '-' (TODO: verify. this works here)
}
tzint := int16(tz)
if tzint == 0 {
tt = time.Unix(tsec, int64(tnsec)).UTC()
} else {
// For Go Time, do not use a descriptive timezone.
// It's unnecessary, and makes it harder to do a reflect.DeepEqual.
// The Offset already tells what the offset should be, if not on UTC and unknown zone name.
// var zoneName = timeLocUTCName(tzint)
tt = time.Unix(tsec, int64(tnsec)).In(time.FixedZone("", int(tzint)*60))
}
return
}
func timeLocUTCName(tzint int16) string {
if tzint == 0 {
return "UTC"
}
var tzname = []byte("UTC+00:00")
//tzname := fmt.Sprintf("UTC%s%02d:%02d", tzsign, tz/60, tz%60) //perf issue using Sprintf. inline below.
//tzhr, tzmin := tz/60, tz%60 //faster if u convert to int first
var tzhr, tzmin int16
if tzint < 0 {
tzname[3] = '-' // (TODO: verify. this works here)
tzhr, tzmin = -tzint/60, (-tzint)%60
} else {
tzhr, tzmin = tzint/60, tzint%60
}
tzname[4] = timeDigits[tzhr/10]
tzname[5] = timeDigits[tzhr%10]
tzname[7] = timeDigits[tzmin/10]
tzname[8] = timeDigits[tzmin%10]
return string(tzname)
//return time.FixedZone(string(tzname), int(tzint)*60)
}
raft-boltdb
===========
This repository provides the `raftboltdb` package. The package exports the
`BoltStore` which is an implementation of both a `LogStore` and `StableStore`.
It is meant to be used as a backend for the `raft` [package
here](https://github.com/hashicorp/raft).
This implementation uses [BoltDB](https://github.com/boltdb/bolt). BoltDB is
a simple key/value store implemented in pure Go, and inspired by LMDB.
package raftboltdb
import (
"errors"
"github.com/boltdb/bolt"
"github.com/hashicorp/raft"
)
const (
// Permissions to use on the db file. This is only used if the
// database file does not exist and needs to be created.
dbFileMode = 0600
)
var (
// Bucket names we perform transactions in
dbLogs = []byte("logs")
dbConf = []byte("conf")
// An error indicating a given key does not exist
ErrKeyNotFound = errors.New("not found")
)
// BoltStore provides access to BoltDB for Raft to store and retrieve
// log entries. It also provides key/value storage, and can be used as
// a LogStore and StableStore.
type BoltStore struct {
// conn is the underlying handle to the db.
conn *bolt.DB
// The path to the Bolt database file
path string
}
// NewBoltStore takes a file path and returns a connected Raft backend.
func NewBoltStore(path string) (*BoltStore, error) {
// Try to connect
handle, err := bolt.Open(path, dbFileMode, nil)
if err != nil {
return nil, err
}
// Create the new store
store := &BoltStore{
conn: handle,
path: path,
}
// Set up our buckets
if err := store.initialize(); err != nil {
store.Close()
return nil, err
}
return store, nil
}
// initialize is used to set up all of the buckets.
func (b *BoltStore) initialize() error {
tx, err := b.conn.Begin(true)
if err != nil {
return err
}
defer tx.Rollback()
// Create all the buckets
if _, err := tx.CreateBucketIfNotExists(dbLogs); err != nil {
return err
}
if _, err := tx.CreateBucketIfNotExists(dbConf); err != nil {
return err
}
return tx.Commit()
}
// Close is used to gracefully close the DB connection.
func (b *BoltStore) Close() error {
return b.conn.Close()
}
// FirstIndex returns the first known index from the Raft log.
func (b *BoltStore) FirstIndex() (uint64, error) {
tx, err := b.conn.Begin(false)
if err != nil {
return 0, err
}
defer tx.Rollback()
curs := tx.Bucket(dbLogs).Cursor()
if first, _ := curs.First(); first == nil {
return 0, nil
} else {
return bytesToUint64(first), nil
}
}
// LastIndex returns the last known index from the Raft log.
func (b *BoltStore) LastIndex() (uint64, error) {
tx, err := b.conn.Begin(false)
if err != nil {
return 0, err
}
defer tx.Rollback()
curs := tx.Bucket(dbLogs).Cursor()
if last, _ := curs.Last(); last == nil {
return 0, nil
} else {
return bytesToUint64(last), nil
}
}
// GetLog is used to retrieve a log from BoltDB at a given index.
func (b *BoltStore) GetLog(idx uint64, log *raft.Log) error {
tx, err := b.conn.Begin(false)
if err != nil {
return err
}
defer tx.Rollback()
bucket := tx.Bucket(dbLogs)
val := bucket.Get(uint64ToBytes(idx))
if val == nil {
return raft.ErrLogNotFound
}
return decodeMsgPack(val, log)
}
// StoreLog is used to store a single raft log
func (b *BoltStore) StoreLog(log *raft.Log) error {
return b.StoreLogs([]*raft.Log{log})
}
// StoreLogs is used to store a set of raft logs
func (b *BoltStore) StoreLogs(logs []*raft.Log) error {
tx, err := b.conn.Begin(true)
if err != nil {
return err
}
defer tx.Rollback()
for _, log := range logs {
key := uint64ToBytes(log.Index)
val, err := encodeMsgPack(log)
if err != nil {
return err
}
bucket := tx.Bucket(dbLogs)
if err := bucket.Put(key, val.Bytes()); err != nil {
return err
}
}
return tx.Commit()
}
// DeleteRange is used to delete logs within a given range inclusively.
func (b *BoltStore) DeleteRange(min, max uint64) error {
minKey := uint64ToBytes(min)
tx, err := b.conn.Begin(true)
if err != nil {
return err
}
defer tx.Rollback()
curs := tx.Bucket(dbLogs).Cursor()
for k, _ := curs.Seek(minKey); k != nil; k, _ = curs.Next() {
// Handle out-of-range log index
if bytesToUint64(k) > max {
break
}
// Delete in-range log index
if err := curs.Delete(); err != nil {
return err
}
}
return tx.Commit()
}
// Set is used to set a key/value set outside of the raft log
func (b *BoltStore) Set(k, v []byte) error {
tx, err := b.conn.Begin(true)
if err != nil {
return err
}
defer tx.Rollback()
bucket := tx.Bucket(dbConf)
if err := bucket.Put(k, v); err != nil {
return err
}
return tx.Commit()
}
// Get is used to retrieve a value from the k/v store by key
func (b *BoltStore) Get(k []byte) ([]byte, error) {
tx, err := b.conn.Begin(false)
if err != nil {
return nil, err
}
defer tx.Rollback()
bucket := tx.Bucket(dbConf)
val := bucket.Get(k)
if val == nil {
return nil, ErrKeyNotFound
}
return append([]byte{}, val...), nil
}
// SetUint64 is like Set, but handles uint64 values
func (b *BoltStore) SetUint64(key []byte, val uint64) error {
return b.Set(key, uint64ToBytes(val))
}
// GetUint64 is like Get, but handles uint64 values
func (b *BoltStore) GetUint64(key []byte) (uint64, error) {
val, err := b.Get(key)
if err != nil {
return 0, err
}
return bytesToUint64(val), nil
}
package raftboltdb
import (
"bytes"
"encoding/binary"
"github.com/hashicorp/go-msgpack/codec"
)
// Decode reverses the encode operation on a byte slice input
func decodeMsgPack(buf []byte, out interface{}) error {
r := bytes.NewBuffer(buf)
hd := codec.MsgpackHandle{}
dec := codec.NewDecoder(r, &hd)
return dec.Decode(out)
}
// Encode writes an encoded object to a new bytes buffer
func encodeMsgPack(in interface{}) (*bytes.Buffer, error) {
buf := bytes.NewBuffer(nil)
hd := codec.MsgpackHandle{}
enc := codec.NewEncoder(buf, &hd)
err := enc.Encode(in)
return buf, err
}
// Converts bytes to an integer
func bytesToUint64(b []byte) uint64 {
return binary.BigEndian.Uint64(b)
}
// Converts a uint to a byte slice
func uint64ToBytes(u uint64) []byte {
buf := make([]byte, 8)
binary.BigEndian.PutUint64(buf, u)
return buf
}
# Compiled Object files, Static and Dynamic libs (Shared Objects)
*.o
*.a
*.so
# Folders
_obj
_test
# Architecture specific extensions/prefixes
*.[568vq]
[568vq].out
*.cgo1.go
*.cgo2.c
_cgo_defun.c
_cgo_gotypes.go
_cgo_export.*
_testmain.go
*.exe
*.test
language: go
go:
- 1.2
- tip
install: make deps
script:
- make integ
notifications:
flowdock:
secure: fZrcf9rlh2IrQrlch1sHkn3YI7SKvjGnAl/zyV5D6NROe1Bbr6d3QRMuCXWWdhJHzjKmXk5rIzbqJhUc0PNF7YjxGNKSzqWMQ56KcvN1k8DzlqxpqkcA3Jbs6fXCWo2fssRtZ7hj/wOP1f5n6cc7kzHDt9dgaYJ6nO2fqNPJiTc=
DEPS = $(go list -f '{{range .TestImports}}{{.}} {{end}}' ./...)
test:
go test -timeout=5s ./...
integ: test
INTEG_TESTS=yes go test -timeout=3s -run=Integ ./...
deps:
go get -d -v ./...
echo $(DEPS) | xargs -n1 go get -d
cov:
INTEG_TESTS=yes gocov test github.com/hashicorp/raft | gocov-html > /tmp/coverage.html
open /tmp/coverage.html
.PHONY: test cov integ deps
raft [![Build Status](https://travis-ci.org/hashicorp/raft.png)](https://travis-ci.org/hashicorp/raft)
====
raft is a [Go](http://www.golang.org) library that manages a replicated
log and can be used with an FSM to manage replicated state machines. It
is library for providing [consensus](http://en.wikipedia.org/wiki/Consensus_(computer_science)).
The use cases for such a library are far-reaching as replicated state
machines are a key component of many distributed systems. They enable
building Consistent, Partition Tolerant (CP) systems, with limited
fault tolerance as well.
## Building
If you wish to build raft you'll need Go version 1.2+ installed.
Please check your installation with:
```
go version
```
## Documentation
For complete documentation, see the associated [Godoc](http://godoc.org/github.com/hashicorp/raft).
To prevent complications with cgo, the primary backend `MDBStore` is in a separate repositoy,
called [raft-mdb](http://github.com/hashicorp/raft-mdb). That is the recommended implementation
for the `LogStore` and `StableStore`.
A pure Go backend using [BoltDB](https://github.com/boltdb/bolt) is also available called
[raft-boltdb](https://github.com/hashicorp/raft-boltdb). It can also be used as a `LogStore`
and `StableStore`.
## Protocol
raft is based on ["Raft: In Search of an Understandable Consensus Algorithm"](https://ramcloud.stanford.edu/wiki/download/attachments/11370504/raft.pdf)
A high level overview of the Raft protocol is described below, but for details please read the full
[Raft paper](https://ramcloud.stanford.edu/wiki/download/attachments/11370504/raft.pdf)
followed by the raft source. Any questions about the raft protocol should be sent to the
[raft-dev mailing list](https://groups.google.com/forum/#!forum/raft-dev).
### Protocol Description
Raft nodes are always in one of three states: follower, candidate or leader. All
nodes initially start out as a follower. In this state, nodes can accept log entries
from a leader and cast votes. If no entries are received for some time, nodes
self-promote to the candidate state. In the candidate state nodes request votes from
their peers. If a candidate receives a quorum of votes, then it is promoted to a leader.
The leader must accept new log entries and replicate to all the other followers.
In addition, if stale reads are not acceptable, all queries must also be performed on
the leader.
Once a cluster has a leader, it is able to accept new log entries. A client can
request that a leader append a new log entry, which is an opaque binary blob to
Raft. The leader then writes the entry to durable storage and attempts to replicate
to a quorum of followers. Once the log entry is considered *committed*, it can be
*applied* to a finite state machine. The finite state machine is application specific,
and is implemented using an interface.
An obvious question relates to the unbounded nature of a replicated log. Raft provides
a mechanism by which the current state is snapshotted, and the log is compacted. Because
of the FSM abstraction, restoring the state of the FSM must result in the same state
as a replay of old logs. This allows Raft to capture the FSM state at a point in time,
and then remove all the logs that were used to reach that state. This is performed automatically
without user intervention, and prevents unbounded disk usage as well as minimizing
time spent replaying logs.
Lastly, there is the issue of updating the peer set when new servers are joining
or existing servers are leaving. As long as a quorum of nodes is available, this
is not an issue as Raft provides mechanisms to dynamically update the peer set.
If a quorum of nodes is unavailable, then this becomes a very challenging issue.
For example, suppose there are only 2 peers, A and B. The quorum size is also
2, meaning both nodes must agree to commit a log entry. If either A or B fails,
it is now impossible to reach quorum. This means the cluster is unable to add,
or remove a node, or commit any additional log entries. This results in *unavailability*.
At this point, manual intervention would be required to remove either A or B,
and to restart the remaining node in bootstrap mode.
A Raft cluster of 3 nodes can tolerate a single node failure, while a cluster
of 5 can tolerate 2 node failures. The recommended configuration is to either
run 3 or 5 raft servers. This maximizes availability without
greatly sacrificing performance.
In terms of performance, Raft is comparable to Paxos. Assuming stable leadership,
committing a log entry requires a single round trip to half of the cluster.
Thus performance is bound by disk I/O and network latency.
package raftbench
// raftbench provides common benchmarking functions which can be used by
// anything which implements the raft.LogStore and raft.StableStore interfaces.
// All functions accept these interfaces and perform benchmarking. This
// makes comparing backend performance easier by sharing the tests.
import (
"github.com/hashicorp/raft"
"testing"
)
func FirstIndex(b *testing.B, store raft.LogStore) {
// Create some fake data
var logs []*raft.Log
for i := 1; i < 10; i++ {
logs = append(logs, &raft.Log{Index: uint64(i), Data: []byte("data")})
}
if err := store.StoreLogs(logs); err != nil {
b.Fatalf("err: %s", err)
}
b.ResetTimer()
// Run FirstIndex a number of times
for n := 0; n < b.N; n++ {
store.FirstIndex()
}
}
func LastIndex(b *testing.B, store raft.LogStore) {
// Create some fake data
var logs []*raft.Log
for i := 1; i < 10; i++ {
logs = append(logs, &raft.Log{Index: uint64(i), Data: []byte("data")})
}
if err := store.StoreLogs(logs); err != nil {
b.Fatalf("err: %s", err)
}
b.ResetTimer()
// Run LastIndex a number of times
for n := 0; n < b.N; n++ {
store.LastIndex()
}
}
func GetLog(b *testing.B, store raft.LogStore) {
// Create some fake data
var logs []*raft.Log
for i := 1; i < 10; i++ {
logs = append(logs, &raft.Log{Index: uint64(i), Data: []byte("data")})
}
if err := store.StoreLogs(logs); err != nil {
b.Fatalf("err: %s", err)
}
b.ResetTimer()
// Run GetLog a number of times
for n := 0; n < b.N; n++ {
if err := store.GetLog(5, new(raft.Log)); err != nil {
b.Fatalf("err: %s", err)
}
}
}
func StoreLog(b *testing.B, store raft.LogStore) {
// Run StoreLog a number of times
for n := 0; n < b.N; n++ {
log := &raft.Log{Index: uint64(n), Data: []byte("data")}
if err := store.StoreLog(log); err != nil {
b.Fatalf("err: %s", err)
}
}
}
func StoreLogs(b *testing.B, store raft.LogStore) {
// Run StoreLogs a number of times. We want to set multiple logs each
// run, so we create 3 logs with incrementing indexes for each iteration.
for n := 0; n < b.N; n++ {
b.StopTimer()
offset := 3 * (n + 1)
logs := []*raft.Log{
&raft.Log{Index: uint64(offset - 2), Data: []byte("data")},
&raft.Log{Index: uint64(offset - 1), Data: []byte("data")},
&raft.Log{Index: uint64(offset), Data: []byte("data")},
}
b.StartTimer()
if err := store.StoreLogs(logs); err != nil {
b.Fatalf("err: %s", err)
}
}
}
func DeleteRange(b *testing.B, store raft.LogStore) {
// Create some fake data. In this case, we create 3 new log entries for each
// test case, and separate them by index in multiples of 10. This allows
// some room so that we can test deleting ranges with "extra" logs to
// to ensure we stop going to the database once our max index is hit.
var logs []*raft.Log
for n := 0; n < b.N; n++ {
offset := 10 * n
for i := offset; i < offset+3; i++ {
logs = append(logs, &raft.Log{Index: uint64(i), Data: []byte("data")})
}
}
if err := store.StoreLogs(logs); err != nil {
b.Fatalf("err: %s", err)
}
b.ResetTimer()
// Delete a range of the data
for n := 0; n < b.N; n++ {
offset := 10 * n
if err := store.DeleteRange(uint64(offset), uint64(offset+9)); err != nil {
b.Fatalf("err: %s", err)
}
}
}
func Set(b *testing.B, store raft.StableStore) {
// Run Set a number of times
for n := 0; n < b.N; n++ {
if err := store.Set([]byte{byte(n)}, []byte("val")); err != nil {
b.Fatalf("err: %s", err)
}
}
}
func Get(b *testing.B, store raft.StableStore) {
// Create some fake data
for i := 1; i < 10; i++ {
if err := store.Set([]byte{byte(i)}, []byte("val")); err != nil {
b.Fatalf("err: %s", err)
}
}
b.ResetTimer()
// Run Get a number of times
for n := 0; n < b.N; n++ {
if _, err := store.Get([]byte{0x05}); err != nil {
b.Fatalf("err: %s", err)
}
}
}
func SetUint64(b *testing.B, store raft.StableStore) {
// Run SetUint64 a number of times
for n := 0; n < b.N; n++ {
if err := store.SetUint64([]byte{byte(n)}, uint64(n)); err != nil {
b.Fatalf("err: %s", err)
}
}
}
func GetUint64(b *testing.B, store raft.StableStore) {
// Create some fake data
for i := 0; i < 10; i++ {
if err := store.SetUint64([]byte{byte(i)}, uint64(i)); err != nil {
b.Fatalf("err: %s", err)
}
}
b.ResetTimer()
// Run GetUint64 a number of times
for n := 0; n < b.N; n++ {
if _, err := store.Get([]byte{0x05}); err != nil {
b.Fatalf("err: %s", err)
}
}
}
package raft
// AppendEntriesRequest is the command used to append entries to the
// replicated log.
type AppendEntriesRequest struct {
// Provide the current term and leader
Term uint64
Leader []byte
// Provide the previous entries for integrity checking
PrevLogEntry uint64
PrevLogTerm uint64
// New entries to commit
Entries []*Log
// Commit index on the leader
LeaderCommitIndex uint64
}
// AppendEntriesResponse is the response returned from an
// AppendEntriesRequest.
type AppendEntriesResponse struct {
// Newer term if leader is out of date
Term uint64
// Last Log is a hint to help accelerate rebuilding slow nodes
LastLog uint64
// We may not succeed if we have a conflicting entry
Success bool
// There are scenarios where this request didn't succeed
// but there's no need to wait/back-off the next attempt.
NoRetryBackoff bool
}
// RequestVoteRequest is the command used by a candidate to ask a Raft peer
// for a vote in an election.
type RequestVoteRequest struct {
// Provide the term and our id
Term uint64
Candidate []byte
// Used to ensure safety
LastLogIndex uint64
LastLogTerm uint64
}
// RequestVoteResponse is the response returned from a RequestVoteRequest.
type RequestVoteResponse struct {
// Newer term if leader is out of date
Term uint64
// Return the peers, so that a node can shutdown on removal
Peers []byte
// Is the vote granted
Granted bool
}
// InstallSnapshotRequest is the command sent to a Raft peer to bootstrap its
// log (and state machine) from a snapshot on another peer.
type InstallSnapshotRequest struct {
Term uint64
Leader []byte
// These are the last index/term included in the snapshot
LastLogIndex uint64
LastLogTerm uint64
// Peer Set in the snapshot
Peers []byte
// Size of the snapshot
Size int64
}
// InstallSnapshotResponse is the response returned from an
// InstallSnapshotRequest.
type InstallSnapshotResponse struct {
Term uint64
Success bool
}
package raft
import (
"fmt"
"io"
"log"
"time"
)
// Config provides any necessary configuration to
// the Raft server
type Config struct {
// Time in follower state without a leader before we attempt an election.
HeartbeatTimeout time.Duration
// Time in candidate state without a leader before we attempt an election.
ElectionTimeout time.Duration
// Time without an Apply() operation before we heartbeat to ensure
// a timely commit. Due to random staggering, may be delayed as much as
// 2x this value.
CommitTimeout time.Duration
// MaxAppendEntries controls the maximum number of append entries
// to send at once. We want to strike a balance between efficiency
// and avoiding waste if the follower is going to reject because of
// an inconsistent log.
MaxAppendEntries int
// If we are a member of a cluster, and RemovePeer is invoked for the
// local node, then we forget all peers and transition into the follower state.
// If ShutdownOnRemove is is set, we additional shutdown Raft. Otherwise,
// we can become a leader of a cluster containing only this node.
ShutdownOnRemove bool
// DisableBootstrapAfterElect is used to turn off EnableSingleNode
// after the node is elected. This is used to prevent self-election
// if the node is removed from the Raft cluster via RemovePeer. Setting
// it to false will keep the bootstrap mode, allowing the node to self-elect
// and potentially bootstrap a separate cluster.
DisableBootstrapAfterElect bool
// TrailingLogs controls how many logs we leave after a snapshot. This is
// used so that we can quickly replay logs on a follower instead of being
// forced to send an entire snapshot.
TrailingLogs uint64
// SnapshotInterval controls how often we check if we should perform a snapshot.
// We randomly stagger between this value and 2x this value to avoid the entire
// cluster from performing a snapshot at once.
SnapshotInterval time.Duration
// SnapshotThreshold controls how many outstanding logs there must be before
// we perform a snapshot. This is to prevent excessive snapshots when we can
// just replay a small set of logs.
SnapshotThreshold uint64
// EnableSingleNode allows for a single node mode of operation. This
// is false by default, which prevents a lone node from electing itself.
// leader.
EnableSingleNode bool
// LeaderLeaseTimeout is used to control how long the "lease" lasts
// for being the leader without being able to contact a quorum
// of nodes. If we reach this interval without contact, we will
// step down as leader.
LeaderLeaseTimeout time.Duration
// StartAsLeader forces Raft to start in the leader state. This should
// never be used except for testing purposes, as it can cause a split-brain.
StartAsLeader bool
// NotifyCh is used to provide a channel that will be notified of leadership
// changes. Raft will block writing to this channel, so it should either be
// buffered or aggressively consumed.
NotifyCh chan<- bool
// LogOutput is used as a sink for logs, unless Logger is specified.
// Defaults to os.Stderr.
LogOutput io.Writer
// Logger is a user-provided logger. If nil, a logger writing to LogOutput
// is used.
Logger *log.Logger
}
// DefaultConfig returns a Config with usable defaults.
func DefaultConfig() *Config {
return &Config{
HeartbeatTimeout: 1000 * time.Millisecond,
ElectionTimeout: 1000 * time.Millisecond,
CommitTimeout: 50 * time.Millisecond,
MaxAppendEntries: 64,
ShutdownOnRemove: true,
DisableBootstrapAfterElect: true,
TrailingLogs: 10240,
SnapshotInterval: 120 * time.Second,
SnapshotThreshold: 8192,
EnableSingleNode: false,
LeaderLeaseTimeout: 500 * time.Millisecond,
}
}
// ValidateConfig is used to validate a sane configuration
func ValidateConfig(config *Config) error {
if config.HeartbeatTimeout < 5*time.Millisecond {
return fmt.Errorf("Heartbeat timeout is too low")
}
if config.ElectionTimeout < 5*time.Millisecond {
return fmt.Errorf("Election timeout is too low")
}
if config.CommitTimeout < time.Millisecond {
return fmt.Errorf("Commit timeout is too low")
}
if config.MaxAppendEntries <= 0 {
return fmt.Errorf("MaxAppendEntries must be positive")
}
if config.MaxAppendEntries > 1024 {
return fmt.Errorf("MaxAppendEntries is too large")
}
if config.SnapshotInterval < 5*time.Millisecond {
return fmt.Errorf("Snapshot interval is too low")
}
if config.LeaderLeaseTimeout < 5*time.Millisecond {
return fmt.Errorf("Leader lease timeout is too low")
}
if config.LeaderLeaseTimeout > config.HeartbeatTimeout {
return fmt.Errorf("Leader lease timeout cannot be larger than heartbeat timeout")
}
if config.ElectionTimeout < config.HeartbeatTimeout {
return fmt.Errorf("Election timeout must be equal or greater than Heartbeat Timeout")
}
return nil
}
package raft
import (
"fmt"
"io"
)
// DiscardSnapshotStore is used to successfully snapshot while
// always discarding the snapshot. This is useful for when the
// log should be truncated but no snapshot should be retained.
// This should never be used for production use, and is only
// suitable for testing.
type DiscardSnapshotStore struct{}
type DiscardSnapshotSink struct{}
// NewDiscardSnapshotStore is used to create a new DiscardSnapshotStore.
func NewDiscardSnapshotStore() *DiscardSnapshotStore {
return &DiscardSnapshotStore{}
}
func (d *DiscardSnapshotStore) Create(index, term uint64, peers []byte) (SnapshotSink, error) {
return &DiscardSnapshotSink{}, nil
}
func (d *DiscardSnapshotStore) List() ([]*SnapshotMeta, error) {
return nil, nil
}
func (d *DiscardSnapshotStore) Open(id string) (*SnapshotMeta, io.ReadCloser, error) {
return nil, nil, fmt.Errorf("open is not supported")
}
func (d *DiscardSnapshotSink) Write(b []byte) (int, error) {
return len(b), nil
}
func (d *DiscardSnapshotSink) Close() error {
return nil
}
func (d *DiscardSnapshotSink) ID() string {
return "discard"
}
func (d *DiscardSnapshotSink) Cancel() error {
return nil
}
package raft
import (
"io"
)
// FSM provides an interface that can be implemented by
// clients to make use of the replicated log.
type FSM interface {
// Apply log is invoked once a log entry is committed.
Apply(*Log) interface{}
// Snapshot is used to support log compaction. This call should
// return an FSMSnapshot which can be used to save a point-in-time
// snapshot of the FSM. Apply and Snapshot are not called in multiple
// threads, but Apply will be called concurrently with Persist. This means
// the FSM should be implemented in a fashion that allows for concurrent
// updates while a snapshot is happening.
Snapshot() (FSMSnapshot, error)
// Restore is used to restore an FSM from a snapshot. It is not called
// concurrently with any other command. The FSM must discard all previous
// state.
Restore(io.ReadCloser) error
}
// FSMSnapshot is returned by an FSM in response to a Snapshot
// It must be safe to invoke FSMSnapshot methods with concurrent
// calls to Apply.
type FSMSnapshot interface {
// Persist should dump all necessary state to the WriteCloser 'sink',
// and call sink.Close() when finished or call sink.Cancel() on error.
Persist(sink SnapshotSink) error
// Release is invoked when we are finished with the snapshot.
Release()
}
package raft
import (
"sync"
"time"
)
// Future is used to represent an action that may occur in the future.
type Future interface {
Error() error
}
// ApplyFuture is used for Apply() and can returns the FSM response.
type ApplyFuture interface {
Future
Response() interface{}
Index() uint64
}
// errorFuture is used to return a static error.
type errorFuture struct {
err error
}
func (e errorFuture) Error() error {
return e.err
}
func (e errorFuture) Response() interface{} {
return nil
}
func (e errorFuture) Index() uint64 {
return 0
}
// deferError can be embedded to allow a future
// to provide an error in the future.
type deferError struct {
err error
errCh chan error
responded bool
}
func (d *deferError) init() {
d.errCh = make(chan error, 1)
}
func (d *deferError) Error() error {
if d.err != nil {
return d.err
}
if d.errCh == nil {
panic("waiting for response on nil channel")
}
d.err = <-d.errCh
return d.err
}
func (d *deferError) respond(err error) {
if d.errCh == nil {
return
}
if d.responded {
return
}
d.errCh <- err
close(d.errCh)
d.responded = true
}
// logFuture is used to apply a log entry and waits until
// the log is considered committed.
type logFuture struct {
deferError
log Log
policy quorumPolicy
response interface{}
dispatch time.Time
}
func (l *logFuture) Response() interface{} {
return l.response
}
func (l *logFuture) Index() uint64 {
return l.log.Index
}
type peerFuture struct {
deferError
peers []string
}
type shutdownFuture struct {
raft *Raft
}
func (s *shutdownFuture) Error() error {
for s.raft.getRoutines() > 0 {
time.Sleep(5 * time.Millisecond)
}
return nil
}
// snapshotFuture is used for waiting on a snapshot to complete.
type snapshotFuture struct {
deferError
}
// reqSnapshotFuture is used for requesting a snapshot start.
// It is only used internally.
type reqSnapshotFuture struct {
deferError
// snapshot details provided by the FSM runner before responding
index uint64
term uint64
peers []string
snapshot FSMSnapshot
}
// restoreFuture is used for requesting an FSM to perform a
// snapshot restore. Used internally only.
type restoreFuture struct {
deferError
ID string
}
// verifyFuture is used to verify the current node is still
// the leader. This is to prevent a stale read.
type verifyFuture struct {
deferError
notifyCh chan *verifyFuture
quorumSize int
votes int
voteLock sync.Mutex
}
// vote is used to respond to a verifyFuture.
// This may block when responding on the notifyCh.
func (v *verifyFuture) vote(leader bool) {
v.voteLock.Lock()
defer v.voteLock.Unlock()
// Guard against having notified already
if v.notifyCh == nil {
return
}
if leader {
v.votes++
if v.votes >= v.quorumSize {
v.notifyCh <- v
v.notifyCh = nil
}
} else {
v.notifyCh <- v
v.notifyCh = nil
}
}
// appendFuture is used for waiting on a pipelined append
// entries RPC.
type appendFuture struct {
deferError
start time.Time
args *AppendEntriesRequest
resp *AppendEntriesResponse
}
func (a *appendFuture) Start() time.Time {
return a.start
}
func (a *appendFuture) Request() *AppendEntriesRequest {
return a.args
}
func (a *appendFuture) Response() *AppendEntriesResponse {
return a.resp
}
package raft
import (
"container/list"
"sync"
)
// QuorumPolicy allows individual logFutures to have different
// commitment rules while still using the inflight mechanism.
type quorumPolicy interface {
// Checks if a commit from a given peer is enough to
// satisfy the commitment rules
Commit() bool
// Checks if a commit is committed
IsCommitted() bool
}
// MajorityQuorum is used by Apply transactions and requires
// a simple majority of nodes.
type majorityQuorum struct {
count int
votesNeeded int
}
func newMajorityQuorum(clusterSize int) *majorityQuorum {
votesNeeded := (clusterSize / 2) + 1
return &majorityQuorum{count: 0, votesNeeded: votesNeeded}
}
func (m *majorityQuorum) Commit() bool {
m.count++
return m.count >= m.votesNeeded
}
func (m *majorityQuorum) IsCommitted() bool {
return m.count >= m.votesNeeded
}
// Inflight is used to track operations that are still in-flight.
type inflight struct {
sync.Mutex
committed *list.List
commitCh chan struct{}
minCommit uint64
maxCommit uint64
operations map[uint64]*logFuture
stopCh chan struct{}
}
// NewInflight returns an inflight struct that notifies
// the provided channel when logs are finished committing.
func newInflight(commitCh chan struct{}) *inflight {
return &inflight{
committed: list.New(),
commitCh: commitCh,
minCommit: 0,
maxCommit: 0,
operations: make(map[uint64]*logFuture),
stopCh: make(chan struct{}),
}
}
// Start is used to mark a logFuture as being inflight. It
// also commits the entry, as it is assumed the leader is
// starting.
func (i *inflight) Start(l *logFuture) {
i.Lock()
defer i.Unlock()
i.start(l)
}
// StartAll is used to mark a list of logFuture's as being
// inflight. It also commits each entry as the leader is
// assumed to be starting.
func (i *inflight) StartAll(logs []*logFuture) {
i.Lock()
defer i.Unlock()
for _, l := range logs {
i.start(l)
}
}
// start is used to mark a single entry as inflight,
// must be invoked with the lock held.
func (i *inflight) start(l *logFuture) {
idx := l.log.Index
i.operations[idx] = l
if idx > i.maxCommit {
i.maxCommit = idx
}
if i.minCommit == 0 {
i.minCommit = idx
}
i.commit(idx)
}
// Cancel is used to cancel all in-flight operations.
// This is done when the leader steps down, and all futures
// are sent the given error.
func (i *inflight) Cancel(err error) {
// Close the channel first to unblock any pending commits
close(i.stopCh)
// Lock after close to avoid deadlock
i.Lock()
defer i.Unlock()
// Respond to all inflight operations
for _, op := range i.operations {
op.respond(err)
}
// Clear all the committed but not processed
for e := i.committed.Front(); e != nil; e = e.Next() {
e.Value.(*logFuture).respond(err)
}
// Clear the map
i.operations = make(map[uint64]*logFuture)
// Clear the list of committed
i.committed = list.New()
// Close the commmitCh
close(i.commitCh)
// Reset indexes
i.minCommit = 0
i.maxCommit = 0
}
// Committed returns all the committed operations in order.
func (i *inflight) Committed() (l *list.List) {
i.Lock()
l, i.committed = i.committed, list.New()
i.Unlock()
return l
}
// Commit is used by leader replication routines to indicate that
// a follower was finished committing a log to disk.
func (i *inflight) Commit(index uint64) {
i.Lock()
defer i.Unlock()
i.commit(index)
}
// CommitRange is used to commit a range of indexes inclusively.
// It is optimized to avoid commits for indexes that are not tracked.
func (i *inflight) CommitRange(minIndex, maxIndex uint64) {
i.Lock()
defer i.Unlock()
// Update the minimum index
minIndex = max(i.minCommit, minIndex)
// Commit each index
for idx := minIndex; idx <= maxIndex; idx++ {
i.commit(idx)
}
}
// commit is used to commit a single index. Must be called with the lock held.
func (i *inflight) commit(index uint64) {
op, ok := i.operations[index]
if !ok {
// Ignore if not in the map, as it may be committed already
return
}
// Check if we've satisfied the commit
if !op.policy.Commit() {
return
}
// Cannot commit if this is not the minimum inflight. This can happen
// if the quorum size changes, meaning a previous commit requires a larger
// quorum that this commit. We MUST block until the previous log is committed,
// otherwise logs will be applied out of order.
if index != i.minCommit {
return
}
NOTIFY:
// Add the operation to the committed list
i.committed.PushBack(op)
// Stop tracking since it is committed
delete(i.operations, index)
// Update the indexes
if index == i.maxCommit {
i.minCommit = 0
i.maxCommit = 0
} else {
i.minCommit++
}
// Check if the next in-flight operation is ready
if i.minCommit != 0 {
op = i.operations[i.minCommit]
if op.policy.IsCommitted() {
index = i.minCommit
goto NOTIFY
}
}
// Async notify of ready operations
asyncNotifyCh(i.commitCh)
}
package raft
import (
"sync"
)
// InmemStore implements the LogStore and StableStore interface.
// It should NOT EVER be used for production. It is used only for
// unit tests. Use the MDBStore implementation instead.
type InmemStore struct {
l sync.RWMutex
lowIndex uint64
highIndex uint64
logs map[uint64]*Log
kv map[string][]byte
kvInt map[string]uint64
}
// NewInmemStore returns a new in-memory backend. Do not ever
// use for production. Only for testing.
func NewInmemStore() *InmemStore {
i := &InmemStore{
logs: make(map[uint64]*Log),
kv: make(map[string][]byte),
kvInt: make(map[string]uint64),
}
return i
}
// FirstIndex implements the LogStore interface.
func (i *InmemStore) FirstIndex() (uint64, error) {
i.l.RLock()
defer i.l.RUnlock()
return i.lowIndex, nil
}
// LastIndex implements the LogStore interface.
func (i *InmemStore) LastIndex() (uint64, error) {
i.l.RLock()
defer i.l.RUnlock()
return i.highIndex, nil
}
// GetLog implements the LogStore interface.
func (i *InmemStore) GetLog(index uint64, log *Log) error {
i.l.RLock()
defer i.l.RUnlock()
l, ok := i.logs[index]
if !ok {
return ErrLogNotFound
}
*log = *l
return nil
}
// StoreLog implements the LogStore interface.
func (i *InmemStore) StoreLog(log *Log) error {
return i.StoreLogs([]*Log{log})
}
// StoreLogs implements the LogStore interface.
func (i *InmemStore) StoreLogs(logs []*Log) error {
i.l.Lock()
defer i.l.Unlock()
for _, l := range logs {
i.logs[l.Index] = l
if i.lowIndex == 0 {
i.lowIndex = l.Index
}
if l.Index > i.highIndex {
i.highIndex = l.Index
}
}
return nil
}
// DeleteRange implements the LogStore interface.
func (i *InmemStore) DeleteRange(min, max uint64) error {
i.l.Lock()
defer i.l.Unlock()
for j := min; j <= max; j++ {
delete(i.logs, j)
}
i.lowIndex = max + 1
return nil
}
// Set implements the StableStore interface.
func (i *InmemStore) Set(key []byte, val []byte) error {
i.l.Lock()
defer i.l.Unlock()
i.kv[string(key)] = val
return nil
}
// Get implements the StableStore interface.
func (i *InmemStore) Get(key []byte) ([]byte, error) {
i.l.RLock()
defer i.l.RUnlock()
return i.kv[string(key)], nil
}
// SetUint64 implements the StableStore interface.
func (i *InmemStore) SetUint64(key []byte, val uint64) error {
i.l.Lock()
defer i.l.Unlock()
i.kvInt[string(key)] = val
return nil
}
// GetUint64 implements the StableStore interface.
func (i *InmemStore) GetUint64(key []byte) (uint64, error) {
i.l.RLock()
defer i.l.RUnlock()
return i.kvInt[string(key)], nil
}
package raft
import (
"fmt"
"io"
"sync"
"time"
)
// NewInmemAddr returns a new in-memory addr with
// a randomly generate UUID as the ID.
func NewInmemAddr() string {
return generateUUID()
}
// inmemPipeline is used to pipeline requests for the in-mem transport.
type inmemPipeline struct {
trans *InmemTransport
peer *InmemTransport
peerAddr string
doneCh chan AppendFuture
inprogressCh chan *inmemPipelineInflight
shutdown bool
shutdownCh chan struct{}
shutdownLock sync.Mutex
}
type inmemPipelineInflight struct {
future *appendFuture
respCh <-chan RPCResponse
}
// InmemTransport Implements the Transport interface, to allow Raft to be
// tested in-memory without going over a network.
type InmemTransport struct {
sync.RWMutex
consumerCh chan RPC
localAddr string
peers map[string]*InmemTransport
pipelines []*inmemPipeline
timeout time.Duration
}
// NewInmemTransport is used to initialize a new transport
// and generates a random local address.
func NewInmemTransport() (string, *InmemTransport) {
addr := NewInmemAddr()
trans := &InmemTransport{
consumerCh: make(chan RPC, 16),
localAddr: addr,
peers: make(map[string]*InmemTransport),
timeout: 50 * time.Millisecond,
}
return addr, trans
}
// SetHeartbeatHandler is used to set optional fast-path for
// heartbeats, not supported for this transport.
func (i *InmemTransport) SetHeartbeatHandler(cb func(RPC)) {
}
// Consumer implements the Transport interface.
func (i *InmemTransport) Consumer() <-chan RPC {
return i.consumerCh
}
// LocalAddr implements the Transport interface.
func (i *InmemTransport) LocalAddr() string {
return i.localAddr
}
// AppendEntriesPipeline returns an interface that can be used to pipeline
// AppendEntries requests.
func (i *InmemTransport) AppendEntriesPipeline(target string) (AppendPipeline, error) {
i.RLock()
peer, ok := i.peers[target]
i.RUnlock()
if !ok {
return nil, fmt.Errorf("failed to connect to peer: %v", target)
}
pipeline := newInmemPipeline(i, peer, target)
i.Lock()
i.pipelines = append(i.pipelines, pipeline)
i.Unlock()
return pipeline, nil
}
// AppendEntries implements the Transport interface.
func (i *InmemTransport) AppendEntries(target string, args *AppendEntriesRequest, resp *AppendEntriesResponse) error {
rpcResp, err := i.makeRPC(target, args, nil, i.timeout)
if err != nil {
return err
}
// Copy the result back
out := rpcResp.Response.(*AppendEntriesResponse)
*resp = *out
return nil
}
// RequestVote implements the Transport interface.
func (i *InmemTransport) RequestVote(target string, args *RequestVoteRequest, resp *RequestVoteResponse) error {
rpcResp, err := i.makeRPC(target, args, nil, i.timeout)
if err != nil {
return err
}
// Copy the result back
out := rpcResp.Response.(*RequestVoteResponse)
*resp = *out
return nil
}
// InstallSnapshot implements the Transport interface.
func (i *InmemTransport) InstallSnapshot(target string, args *InstallSnapshotRequest, resp *InstallSnapshotResponse, data io.Reader) error {
rpcResp, err := i.makeRPC(target, args, data, 10*i.timeout)
if err != nil {
return err
}
// Copy the result back
out := rpcResp.Response.(*InstallSnapshotResponse)
*resp = *out
return nil
}
func (i *InmemTransport) makeRPC(target string, args interface{}, r io.Reader, timeout time.Duration) (rpcResp RPCResponse, err error) {
i.RLock()
peer, ok := i.peers[target]
i.RUnlock()
if !ok {
err = fmt.Errorf("failed to connect to peer: %v", target)
return
}
// Send the RPC over
respCh := make(chan RPCResponse)
peer.consumerCh <- RPC{
Command: args,
Reader: r,
RespChan: respCh,
}
// Wait for a response
select {
case rpcResp = <-respCh:
if rpcResp.Error != nil {
err = rpcResp.Error
}
case <-time.After(timeout):
err = fmt.Errorf("command timed out")
}
return
}
// EncodePeer implements the Transport interface. It uses the UUID as the
// address directly.
func (i *InmemTransport) EncodePeer(p string) []byte {
return []byte(p)
}
// DecodePeer implements the Transport interface. It wraps the UUID in an
// InmemAddr.
func (i *InmemTransport) DecodePeer(buf []byte) string {
return string(buf)
}
// Connect is used to connect this transport to another transport for
// a given peer name. This allows for local routing.
func (i *InmemTransport) Connect(peer string, trans *InmemTransport) {
i.Lock()
defer i.Unlock()
i.peers[peer] = trans
}
// Disconnect is used to remove the ability to route to a given peer.
func (i *InmemTransport) Disconnect(peer string) {
i.Lock()
defer i.Unlock()
delete(i.peers, peer)
// Disconnect any pipelines
n := len(i.pipelines)
for idx := 0; idx < n; idx++ {
if i.pipelines[idx].peerAddr == peer {
i.pipelines[idx].Close()
i.pipelines[idx], i.pipelines[n-1] = i.pipelines[n-1], nil
idx--
n--
}
}
i.pipelines = i.pipelines[:n]
}
// DisconnectAll is used to remove all routes to peers.
func (i *InmemTransport) DisconnectAll() {
i.Lock()
defer i.Unlock()
i.peers = make(map[string]*InmemTransport)
// Handle pipelines
for _, pipeline := range i.pipelines {
pipeline.Close()
}
i.pipelines = nil
}
func newInmemPipeline(trans *InmemTransport, peer *InmemTransport, addr string) *inmemPipeline {
i := &inmemPipeline{
trans: trans,
peer: peer,
peerAddr: addr,
doneCh: make(chan AppendFuture, 16),
inprogressCh: make(chan *inmemPipelineInflight, 16),
shutdownCh: make(chan struct{}),
}
go i.decodeResponses()
return i
}
func (i *inmemPipeline) decodeResponses() {
timeout := i.trans.timeout
for {
select {
case inp := <-i.inprogressCh:
var timeoutCh <-chan time.Time
if timeout > 0 {
timeoutCh = time.After(timeout)
}
select {
case rpcResp := <-inp.respCh:
// Copy the result back
*inp.future.resp = *rpcResp.Response.(*AppendEntriesResponse)
inp.future.respond(rpcResp.Error)
select {
case i.doneCh <- inp.future:
case <-i.shutdownCh:
return
}
case <-timeoutCh:
inp.future.respond(fmt.Errorf("command timed out"))
select {
case i.doneCh <- inp.future:
case <-i.shutdownCh:
return
}
case <-i.shutdownCh:
return
}
case <-i.shutdownCh:
return
}
}
}
func (i *inmemPipeline) AppendEntries(args *AppendEntriesRequest, resp *AppendEntriesResponse) (AppendFuture, error) {
// Create a new future
future := &appendFuture{
start: time.Now(),
args: args,
resp: resp,
}
future.init()
// Handle a timeout
var timeout <-chan time.Time
if i.trans.timeout > 0 {
timeout = time.After(i.trans.timeout)
}
// Send the RPC over
respCh := make(chan RPCResponse, 1)
rpc := RPC{
Command: args,
RespChan: respCh,
}
select {
case i.peer.consumerCh <- rpc:
case <-timeout:
return nil, fmt.Errorf("command enqueue timeout")
case <-i.shutdownCh:
return nil, ErrPipelineShutdown
}
// Send to be decoded
select {
case i.inprogressCh <- &inmemPipelineInflight{future, respCh}:
return future, nil
case <-i.shutdownCh:
return nil, ErrPipelineShutdown
}
}
func (i *inmemPipeline) Consumer() <-chan AppendFuture {
return i.doneCh
}
func (i *inmemPipeline) Close() error {
i.shutdownLock.Lock()
defer i.shutdownLock.Unlock()
if i.shutdown {
return nil
}
i.shutdown = true
close(i.shutdownCh)
return nil
}
package raft
// LogType describes various types of log entries.
type LogType uint8
const (
// LogCommand is applied to a user FSM.
LogCommand LogType = iota
// LogNoop is used to assert leadership.
LogNoop
// LogAddPeer is used to add a new peer.
LogAddPeer
// LogRemovePeer is used to remove an existing peer.
LogRemovePeer
// LogBarrier is used to ensure all preceding operations have been
// applied to the FSM. It is similar to LogNoop, but instead of returning
// once committed, it only returns once the FSM manager acks it. Otherwise
// it is possible there are operations committed but not yet applied to
// the FSM.
LogBarrier
)
// Log entries are replicated to all members of the Raft cluster
// and form the heart of the replicated state machine.
type Log struct {
Index uint64
Term uint64
Type LogType
Data []byte
// peer is not exported since it is not transmitted, only used
// internally to construct the Data field.
peer string
}
// LogStore is used to provide an interface for storing
// and retrieving logs in a durable fashion.
type LogStore interface {
// Returns the first index written. 0 for no entries.
FirstIndex() (uint64, error)
// Returns the last index written. 0 for no entries.
LastIndex() (uint64, error)
// Gets a log entry at a given index.
GetLog(index uint64, log *Log) error
// Stores a log entry.
StoreLog(log *Log) error
// Stores multiple log entries.
StoreLogs(logs []*Log) error
// Deletes a range of log entries. The range is inclusive.
DeleteRange(min, max uint64) error
}
package raft
import (
"fmt"
"sync"
)
// LogCache wraps any LogStore implementation to provide an
// in-memory ring buffer. This is used to cache access to
// the recently written entries. For implementations that do not
// cache themselves, this can provide a substantial boost by
// avoiding disk I/O on recent entries.
type LogCache struct {
store LogStore
cache []*Log
l sync.RWMutex
}
// NewLogCache is used to create a new LogCache with the
// given capacity and backend store.
func NewLogCache(capacity int, store LogStore) (*LogCache, error) {
if capacity <= 0 {
return nil, fmt.Errorf("capacity must be positive")
}
c := &LogCache{
store: store,
cache: make([]*Log, capacity),
}
return c, nil
}
func (c *LogCache) GetLog(idx uint64, log *Log) error {
// Check the buffer for an entry
c.l.RLock()
cached := c.cache[idx%uint64(len(c.cache))]
c.l.RUnlock()
// Check if entry is valid
if cached != nil && cached.Index == idx {
*log = *cached
return nil
}
// Forward request on cache miss
return c.store.GetLog(idx, log)
}
func (c *LogCache) StoreLog(log *Log) error {
return c.StoreLogs([]*Log{log})
}
func (c *LogCache) StoreLogs(logs []*Log) error {
// Insert the logs into the ring buffer
c.l.Lock()
for _, l := range logs {
c.cache[l.Index%uint64(len(c.cache))] = l
}
c.l.Unlock()
return c.store.StoreLogs(logs)
}
func (c *LogCache) FirstIndex() (uint64, error) {
return c.store.FirstIndex()
}
func (c *LogCache) LastIndex() (uint64, error) {
return c.store.LastIndex()
}
func (c *LogCache) DeleteRange(min, max uint64) error {
// Invalidate the cache on deletes
c.l.Lock()
c.cache = make([]*Log, len(c.cache))
c.l.Unlock()
return c.store.DeleteRange(min, max)
}
package raft
import (
"bytes"
"encoding/json"
"io/ioutil"
"os"
"path/filepath"
"sync"
)
const (
jsonPeerPath = "peers.json"
)
// PeerStore provides an interface for persistent storage and
// retrieval of peers. We use a separate interface than StableStore
// since the peers may need to be edited by a human operator. For example,
// in a two node cluster, the failure of either node requires human intervention
// since consensus is impossible.
type PeerStore interface {
// Peers returns the list of known peers.
Peers() ([]string, error)
// SetPeers sets the list of known peers. This is invoked when a peer is
// added or removed.
SetPeers([]string) error
}
// StaticPeers is used to provide a static list of peers.
type StaticPeers struct {
StaticPeers []string
l sync.Mutex
}
// Peers implements the PeerStore interface.
func (s *StaticPeers) Peers() ([]string, error) {
s.l.Lock()
peers := s.StaticPeers
s.l.Unlock()
return peers, nil
}
// SetPeers implements the PeerStore interface.
func (s *StaticPeers) SetPeers(p []string) error {
s.l.Lock()
s.StaticPeers = p
s.l.Unlock()
return nil
}
// JSONPeers is used to provide peer persistence on disk in the form
// of a JSON file. This allows human operators to manipulate the file.
type JSONPeers struct {
l sync.Mutex
path string
trans Transport
}
// NewJSONPeers creates a new JSONPeers store. Requires a transport
// to handle the serialization of network addresses.
func NewJSONPeers(base string, trans Transport) *JSONPeers {
path := filepath.Join(base, jsonPeerPath)
store := &JSONPeers{
path: path,
trans: trans,
}
return store
}
// Peers implements the PeerStore interface.
func (j *JSONPeers) Peers() ([]string, error) {
j.l.Lock()
defer j.l.Unlock()
// Read the file
buf, err := ioutil.ReadFile(j.path)
if err != nil && !os.IsNotExist(err) {
return nil, err
}
// Check for no peers
if len(buf) == 0 {
return nil, nil
}
// Decode the peers
var peerSet []string
dec := json.NewDecoder(bytes.NewReader(buf))
if err := dec.Decode(&peerSet); err != nil {
return nil, err
}
// Deserialize each peer
var peers []string
for _, p := range peerSet {
peers = append(peers, j.trans.DecodePeer([]byte(p)))
}
return peers, nil
}
// SetPeers implements the PeerStore interface.
func (j *JSONPeers) SetPeers(peers []string) error {
j.l.Lock()
defer j.l.Unlock()
// Encode each peer
var peerSet []string
for _, p := range peers {
peerSet = append(peerSet, string(j.trans.EncodePeer(p)))
}
// Convert to JSON
var buf bytes.Buffer
enc := json.NewEncoder(&buf)
if err := enc.Encode(peerSet); err != nil {
return err
}
// Write out as JSON
return ioutil.WriteFile(j.path, buf.Bytes(), 0755)
}
package raft
import (
"io"
)
// SnapshotMeta is for metadata of a snapshot.
type SnapshotMeta struct {
ID string // ID is opaque to the store, and is used for opening
Index uint64
Term uint64
Peers []byte
Size int64
}
// SnapshotStore interface is used to allow for flexible implementations
// of snapshot storage and retrieval. For example, a client could implement
// a shared state store such as S3, allowing new nodes to restore snapshots
// without steaming from the leader.
type SnapshotStore interface {
// Create is used to begin a snapshot at a given index and term,
// with the current peer set already encoded.
Create(index, term uint64, peers []byte) (SnapshotSink, error)
// List is used to list the available snapshots in the store.
// It should return then in descending order, with the highest index first.
List() ([]*SnapshotMeta, error)
// Open takes a snapshot ID and provides a ReadCloser. Once close is
// called it is assumed the snapshot is no longer needed.
Open(id string) (*SnapshotMeta, io.ReadCloser, error)
}
// SnapshotSink is returned by StartSnapshot. The FSM will Write state
// to the sink and call Close on completion. On error, Cancel will be invoked.
type SnapshotSink interface {
io.WriteCloser
ID() string
Cancel() error
}
package raft
// StableStore is used to provide stable storage
// of key configurations to ensure safety.
type StableStore interface {
Set(key []byte, val []byte) error
// Get returns the value for key, or an empty byte slice if key was not found.
Get(key []byte) ([]byte, error)
SetUint64(key []byte, val uint64) error
// GetUint64 returns the uint64 value for key, or 0 if key was not found.
GetUint64(key []byte) (uint64, error)
}
package raft
import (
"sync/atomic"
)
// RaftState captures the state of a Raft node: Follower, Candidate, Leader,
// or Shutdown.
type RaftState uint32
const (
// Follower is the initial state of a Raft node.
Follower RaftState = iota
// Candidate is one of the valid states of a Raft node.
Candidate
// Leader is one of the valid states of a Raft node.
Leader
// Shutdown is the terminal state of a Raft node.
Shutdown
)
func (s RaftState) String() string {
switch s {
case Follower:
return "Follower"
case Candidate:
return "Candidate"
case Leader:
return "Leader"
case Shutdown:
return "Shutdown"
default:
return "Unknown"
}
}
// raftState is used to maintain various state variables
// and provides an interface to set/get the variables in a
// thread safe manner.
type raftState struct {
// The current term, cache of StableStore
currentTerm uint64
// Cache the latest log from LogStore
LastLogIndex uint64
LastLogTerm uint64
// Highest committed log entry
commitIndex uint64
// Last applied log to the FSM
lastApplied uint64
// Cache the latest snapshot index/term
lastSnapshotIndex uint64
lastSnapshotTerm uint64
// Tracks the number of live routines
runningRoutines int32
// The current state
state RaftState
}
func (r *raftState) getState() RaftState {
stateAddr := (*uint32)(&r.state)
return RaftState(atomic.LoadUint32(stateAddr))
}
func (r *raftState) setState(s RaftState) {
stateAddr := (*uint32)(&r.state)
atomic.StoreUint32(stateAddr, uint32(s))
}
func (r *raftState) getCurrentTerm() uint64 {
return atomic.LoadUint64(&r.currentTerm)
}
func (r *raftState) setCurrentTerm(term uint64) {
atomic.StoreUint64(&r.currentTerm, term)
}
func (r *raftState) getLastLogIndex() uint64 {
return atomic.LoadUint64(&r.LastLogIndex)
}
func (r *raftState) setLastLogIndex(term uint64) {
atomic.StoreUint64(&r.LastLogIndex, term)
}
func (r *raftState) getLastLogTerm() uint64 {
return atomic.LoadUint64(&r.LastLogTerm)
}
func (r *raftState) setLastLogTerm(term uint64) {
atomic.StoreUint64(&r.LastLogTerm, term)
}
func (r *raftState) getCommitIndex() uint64 {
return atomic.LoadUint64(&r.commitIndex)
}
func (r *raftState) setCommitIndex(term uint64) {
atomic.StoreUint64(&r.commitIndex, term)
}
func (r *raftState) getLastApplied() uint64 {
return atomic.LoadUint64(&r.lastApplied)
}
func (r *raftState) setLastApplied(term uint64) {
atomic.StoreUint64(&r.lastApplied, term)
}
func (r *raftState) getLastSnapshotIndex() uint64 {
return atomic.LoadUint64(&r.lastSnapshotIndex)
}
func (r *raftState) setLastSnapshotIndex(term uint64) {
atomic.StoreUint64(&r.lastSnapshotIndex, term)
}
func (r *raftState) getLastSnapshotTerm() uint64 {
return atomic.LoadUint64(&r.lastSnapshotTerm)
}
func (r *raftState) setLastSnapshotTerm(term uint64) {
atomic.StoreUint64(&r.lastSnapshotTerm, term)
}
func (r *raftState) incrRoutines() {
atomic.AddInt32(&r.runningRoutines, 1)
}
func (r *raftState) decrRoutines() {
atomic.AddInt32(&r.runningRoutines, -1)
}
func (r *raftState) getRoutines() int32 {
return atomic.LoadInt32(&r.runningRoutines)
}
// Start a goroutine and properly handle the race between a routine
// starting and incrementing, and exiting and decrementing.
func (r *raftState) goFunc(f func()) {
r.incrRoutines()
go func() {
defer r.decrRoutines()
f()
}()
}
// getLastIndex returns the last index in stable storage.
// Either from the last log or from the last snapshot.
func (r *raftState) getLastIndex() uint64 {
return max(r.getLastLogIndex(), r.getLastSnapshotIndex())
}
// getLastEntry returns the last index and term in stable storage.
// Either from the last log or from the last snapshot.
func (r *raftState) getLastEntry() (uint64, uint64) {
if r.getLastLogIndex() >= r.getLastSnapshotIndex() {
return r.getLastLogIndex(), r.getLastLogTerm()
}
return r.getLastSnapshotIndex(), r.getLastSnapshotTerm()
}
package raft
import (
"errors"
"io"
"log"
"net"
"time"
)
var (
errNotAdvertisable = errors.New("local bind address is not advertisable")
errNotTCP = errors.New("local address is not a TCP address")
)
// TCPStreamLayer implements StreamLayer interface for plain TCP.
type TCPStreamLayer struct {
advertise net.Addr
listener *net.TCPListener
}
// NewTCPTransport returns a NetworkTransport that is built on top of
// a TCP streaming transport layer.
func NewTCPTransport(
bindAddr string,
advertise net.Addr,
maxPool int,
timeout time.Duration,
logOutput io.Writer,
) (*NetworkTransport, error) {
return newTCPTransport(bindAddr, advertise, maxPool, timeout, func(stream StreamLayer) *NetworkTransport {
return NewNetworkTransport(stream, maxPool, timeout, logOutput)
})
}
// NewTCPTransportWithLogger returns a NetworkTransport that is built on top of
// a TCP streaming transport layer, with log output going to the supplied Logger
func NewTCPTransportWithLogger(
bindAddr string,
advertise net.Addr,
maxPool int,
timeout time.Duration,
logger *log.Logger,
) (*NetworkTransport, error) {
return newTCPTransport(bindAddr, advertise, maxPool, timeout, func(stream StreamLayer) *NetworkTransport {
return NewNetworkTransportWithLogger(stream, maxPool, timeout, logger)
})
}
func newTCPTransport(bindAddr string,
advertise net.Addr,
maxPool int,
timeout time.Duration,
transportCreator func(stream StreamLayer) *NetworkTransport) (*NetworkTransport, error) {
// Try to bind
list, err := net.Listen("tcp", bindAddr)
if err != nil {
return nil, err
}
// Create stream
stream := &TCPStreamLayer{
advertise: advertise,
listener: list.(*net.TCPListener),
}
// Verify that we have a usable advertise address
addr, ok := stream.Addr().(*net.TCPAddr)
if !ok {
list.Close()
return nil, errNotTCP
}
if addr.IP.IsUnspecified() {
list.Close()
return nil, errNotAdvertisable
}
// Create the network transport
trans := transportCreator(stream)
return trans, nil
}
// Dial implements the StreamLayer interface.
func (t *TCPStreamLayer) Dial(address string, timeout time.Duration) (net.Conn, error) {
return net.DialTimeout("tcp", address, timeout)
}
// Accept implements the net.Listener interface.
func (t *TCPStreamLayer) Accept() (c net.Conn, err error) {
return t.listener.Accept()
}
// Close implements the net.Listener interface.
func (t *TCPStreamLayer) Close() (err error) {
return t.listener.Close()
}
// Addr implements the net.Listener interface.
func (t *TCPStreamLayer) Addr() net.Addr {
// Use an advertise addr if provided
if t.advertise != nil {
return t.advertise
}
return t.listener.Addr()
}
package raft
import (
"io"
"time"
)
// RPCResponse captures both a response and a potential error.
type RPCResponse struct {
Response interface{}
Error error
}
// RPC has a command, and provides a response mechanism.
type RPC struct {
Command interface{}
Reader io.Reader // Set only for InstallSnapshot
RespChan chan<- RPCResponse
}
// Respond is used to respond with a response, error or both
func (r *RPC) Respond(resp interface{}, err error) {
r.RespChan <- RPCResponse{resp, err}
}
// Transport provides an interface for network transports
// to allow Raft to communicate with other nodes.
type Transport interface {
// Consumer returns a channel that can be used to
// consume and respond to RPC requests.
Consumer() <-chan RPC
// LocalAddr is used to return our local address to distinguish from our peers.
LocalAddr() string
// AppendEntriesPipeline returns an interface that can be used to pipeline
// AppendEntries requests.
AppendEntriesPipeline(target string) (AppendPipeline, error)
// AppendEntries sends the appropriate RPC to the target node.
AppendEntries(target string, args *AppendEntriesRequest, resp *AppendEntriesResponse) error
// RequestVote sends the appropriate RPC to the target node.
RequestVote(target string, args *RequestVoteRequest, resp *RequestVoteResponse) error
// InstallSnapshot is used to push a snapshot down to a follower. The data is read from
// the ReadCloser and streamed to the client.
InstallSnapshot(target string, args *InstallSnapshotRequest, resp *InstallSnapshotResponse, data io.Reader) error
// EncodePeer is used to serialize a peer name.
EncodePeer(string) []byte
// DecodePeer is used to deserialize a peer name.
DecodePeer([]byte) string
// SetHeartbeatHandler is used to setup a heartbeat handler
// as a fast-pass. This is to avoid head-of-line blocking from
// disk IO. If a Transport does not support this, it can simply
// ignore the call, and push the heartbeat onto the Consumer channel.
SetHeartbeatHandler(cb func(rpc RPC))
}
// AppendPipeline is used for pipelining AppendEntries requests. It is used
// to increase the replication throughput by masking latency and better
// utilizing bandwidth.
type AppendPipeline interface {
// AppendEntries is used to add another request to the pipeline.
// The send may block which is an effective form of back-pressure.
AppendEntries(args *AppendEntriesRequest, resp *AppendEntriesResponse) (AppendFuture, error)
// Consumer returns a channel that can be used to consume
// response futures when they are ready.
Consumer() <-chan AppendFuture
// Closes pipeline and cancels all inflight RPCs
Close() error
}
// AppendFuture is used to return information about a pipelined AppendEntries request.
type AppendFuture interface {
Future
Start() time.Time
Request() *AppendEntriesRequest
Response() *AppendEntriesResponse
}
package raft
import (
"bytes"
crand "crypto/rand"
"encoding/binary"
"fmt"
"math"
"math/big"
"math/rand"
"time"
"github.com/hashicorp/go-msgpack/codec"
)
func init() {
// Ensure we use a high-entropy seed for the psuedo-random generator
rand.Seed(newSeed())
}
// returns an int64 from a crypto random source
// can be used to seed a source for a math/rand.
func newSeed() int64 {
r, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64))
if err != nil {
panic(fmt.Errorf("failed to read random bytes: %v", err))
}
return r.Int64()
}
// randomTimeout returns a value that is between the minVal and 2x minVal.
func randomTimeout(minVal time.Duration) <-chan time.Time {
if minVal == 0 {
return nil
}
extra := (time.Duration(rand.Int63()) % minVal)
return time.After(minVal + extra)
}
// min returns the minimum.
func min(a, b uint64) uint64 {
if a <= b {
return a
}
return b
}
// max returns the maximum.
func max(a, b uint64) uint64 {
if a >= b {
return a
}
return b
}
// generateUUID is used to generate a random UUID.
func generateUUID() string {
buf := make([]byte, 16)
if _, err := crand.Read(buf); err != nil {
panic(fmt.Errorf("failed to read random bytes: %v", err))
}
return fmt.Sprintf("%08x-%04x-%04x-%04x-%12x",
buf[0:4],
buf[4:6],
buf[6:8],
buf[8:10],
buf[10:16])
}
// asyncNotify is used to do an async channel send to
// a list of channels. This will not block.
func asyncNotify(chans []chan struct{}) {
for _, ch := range chans {
asyncNotifyCh(ch)
}
}
// asyncNotifyCh is used to do an async channel send
// to a single channel without blocking.
func asyncNotifyCh(ch chan struct{}) {
select {
case ch <- struct{}{}:
default:
}
}
// asyncNotifyBool is used to do an async notification
// on a bool channel.
func asyncNotifyBool(ch chan bool, v bool) {
select {
case ch <- v:
default:
}
}
// ExcludePeer is used to exclude a single peer from a list of peers.
func ExcludePeer(peers []string, peer string) []string {
otherPeers := make([]string, 0, len(peers))
for _, p := range peers {
if p != peer {
otherPeers = append(otherPeers, p)
}
}
return otherPeers
}
// PeerContained checks if a given peer is contained in a list.
func PeerContained(peers []string, peer string) bool {
for _, p := range peers {
if p == peer {
return true
}
}
return false
}
// AddUniquePeer is used to add a peer to a list of existing
// peers only if it is not already contained.
func AddUniquePeer(peers []string, peer string) []string {
if PeerContained(peers, peer) {
return peers
}
return append(peers, peer)
}
// encodePeers is used to serialize a list of peers.
func encodePeers(peers []string, trans Transport) []byte {
// Encode each peer
var encPeers [][]byte
for _, p := range peers {
encPeers = append(encPeers, trans.EncodePeer(p))
}
// Encode the entire array
buf, err := encodeMsgPack(encPeers)
if err != nil {
panic(fmt.Errorf("failed to encode peers: %v", err))
}
return buf.Bytes()
}
// decodePeers is used to deserialize a list of peers.
func decodePeers(buf []byte, trans Transport) []string {
// Decode the buffer first
var encPeers [][]byte
if err := decodeMsgPack(buf, &encPeers); err != nil {
panic(fmt.Errorf("failed to decode peers: %v", err))
}
// Deserialize each peer
var peers []string
for _, enc := range encPeers {
peers = append(peers, trans.DecodePeer(enc))
}
return peers
}
// Decode reverses the encode operation on a byte slice input.
func decodeMsgPack(buf []byte, out interface{}) error {
r := bytes.NewBuffer(buf)
hd := codec.MsgpackHandle{}
dec := codec.NewDecoder(r, &hd)
return dec.Decode(out)
}
// Encode writes an encoded object to a new bytes buffer.
func encodeMsgPack(in interface{}) (*bytes.Buffer, error) {
buf := bytes.NewBuffer(nil)
hd := codec.MsgpackHandle{}
enc := codec.NewEncoder(buf, &hd)
err := enc.Encode(in)
return buf, err
}
// Converts bytes to an integer.
func bytesToUint64(b []byte) uint64 {
return binary.BigEndian.Uint64(b)
}
// Converts a uint64 to a byte slice.
func uint64ToBytes(u uint64) []byte {
buf := make([]byte, 8)
binary.BigEndian.PutUint64(buf, u)
return buf
}
// backoff is used to compute an exponential backoff
// duration. Base time is scaled by the current round,
// up to some maximum scale factor.
func backoff(base time.Duration, round, limit uint64) time.Duration {
power := min(round, limit)
for power > 2 {
base *= 2
power--
}
return base
}
The MIT License (MIT)
Copyright (c) 2013-2014 Errplane Inc.
Copyright (c) 2013-2015 Errplane Inc.
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
......
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