Support http service graceful restart (#416)
* support http service graceful restart * fix dependenciesrelease/v1.1
Lunny Xiao
7 years ago
committed by
GitHub
parent
fa60cf0ea4
commit
527c2dd665
@ -0,0 +1,21 @@
|
||||
The MIT License (MIT)
|
||||
|
||||
Copyright (c) 2014 Ben Johnson
|
||||
|
||||
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.
|
||||
@ -0,0 +1,104 @@
|
||||
clock [](https://drone.io/github.com/benbjohnson/clock/latest) [](https://coveralls.io/r/benbjohnson/clock?branch=master) [](https://godoc.org/github.com/benbjohnson/clock) 
|
||||
=====
|
||||
|
||||
Clock is a small library for mocking time in Go. It provides an interface
|
||||
around the standard library's [`time`][time] package so that the application
|
||||
can use the realtime clock while tests can use the mock clock.
|
||||
|
||||
[time]: http://golang.org/pkg/time/
|
||||
|
||||
|
||||
## Usage
|
||||
|
||||
### Realtime Clock
|
||||
|
||||
Your application can maintain a `Clock` variable that will allow realtime and
|
||||
mock clocks to be interchangable. For example, if you had an `Application` type:
|
||||
|
||||
```go
|
||||
import "github.com/benbjohnson/clock"
|
||||
|
||||
type Application struct {
|
||||
Clock clock.Clock
|
||||
}
|
||||
```
|
||||
|
||||
You could initialize it to use the realtime clock like this:
|
||||
|
||||
```go
|
||||
var app Application
|
||||
app.Clock = clock.New()
|
||||
...
|
||||
```
|
||||
|
||||
Then all timers and time-related functionality should be performed from the
|
||||
`Clock` variable.
|
||||
|
||||
|
||||
### Mocking time
|
||||
|
||||
In your tests, you will want to use a `Mock` clock:
|
||||
|
||||
```go
|
||||
import (
|
||||
"testing"
|
||||
|
||||
"github.com/benbjohnson/clock"
|
||||
)
|
||||
|
||||
func TestApplication_DoSomething(t *testing.T) {
|
||||
mock := clock.NewMock()
|
||||
app := Application{Clock: mock}
|
||||
...
|
||||
}
|
||||
```
|
||||
|
||||
Now that you've initialized your application to use the mock clock, you can
|
||||
adjust the time programmatically. The mock clock always starts from the Unix
|
||||
epoch (midnight, Jan 1, 1970 UTC).
|
||||
|
||||
|
||||
### Controlling time
|
||||
|
||||
The mock clock provides the same functions that the standard library's `time`
|
||||
package provides. For example, to find the current time, you use the `Now()`
|
||||
function:
|
||||
|
||||
```go
|
||||
mock := clock.NewMock()
|
||||
|
||||
// Find the current time.
|
||||
mock.Now().UTC() // 1970-01-01 00:00:00 +0000 UTC
|
||||
|
||||
// Move the clock forward.
|
||||
mock.Add(2 * time.Hour)
|
||||
|
||||
// Check the time again. It's 2 hours later!
|
||||
mock.Now().UTC() // 1970-01-01 02:00:00 +0000 UTC
|
||||
```
|
||||
|
||||
Timers and Tickers are also controlled by this same mock clock. They will only
|
||||
execute when the clock is moved forward:
|
||||
|
||||
```
|
||||
mock := clock.NewMock()
|
||||
count := 0
|
||||
|
||||
// Kick off a timer to increment every 1 mock second.
|
||||
go func() {
|
||||
ticker := clock.Ticker(1 * time.Second)
|
||||
for {
|
||||
<-ticker.C
|
||||
count++
|
||||
}
|
||||
}()
|
||||
runtime.Gosched()
|
||||
|
||||
// Move the clock forward 10 second.
|
||||
mock.Add(10 * time.Second)
|
||||
|
||||
// This prints 10.
|
||||
fmt.Println(count)
|
||||
```
|
||||
|
||||
|
||||
@ -0,0 +1,363 @@
|
||||
package clock
|
||||
|
||||
import (
|
||||
"runtime"
|
||||
"sort"
|
||||
"sync"
|
||||
"time"
|
||||
)
|
||||
|
||||
// Clock represents an interface to the functions in the standard library time
|
||||
// package. Two implementations are available in the clock package. The first
|
||||
// is a real-time clock which simply wraps the time package's functions. The
|
||||
// second is a mock clock which will only make forward progress when
|
||||
// programmatically adjusted.
|
||||
type Clock interface {
|
||||
After(d time.Duration) <-chan time.Time
|
||||
AfterFunc(d time.Duration, f func()) *Timer
|
||||
Now() time.Time
|
||||
Sleep(d time.Duration)
|
||||
Tick(d time.Duration) <-chan time.Time
|
||||
Ticker(d time.Duration) *Ticker
|
||||
Timer(d time.Duration) *Timer
|
||||
}
|
||||
|
||||
// New returns an instance of a real-time clock.
|
||||
func New() Clock {
|
||||
return &clock{}
|
||||
}
|
||||
|
||||
// clock implements a real-time clock by simply wrapping the time package functions.
|
||||
type clock struct{}
|
||||
|
||||
func (c *clock) After(d time.Duration) <-chan time.Time { return time.After(d) }
|
||||
|
||||
func (c *clock) AfterFunc(d time.Duration, f func()) *Timer {
|
||||
return &Timer{timer: time.AfterFunc(d, f)}
|
||||
}
|
||||
|
||||
func (c *clock) Now() time.Time { return time.Now() }
|
||||
|
||||
func (c *clock) Sleep(d time.Duration) { time.Sleep(d) }
|
||||
|
||||
func (c *clock) Tick(d time.Duration) <-chan time.Time { return time.Tick(d) }
|
||||
|
||||
func (c *clock) Ticker(d time.Duration) *Ticker {
|
||||
t := time.NewTicker(d)
|
||||
return &Ticker{C: t.C, ticker: t}
|
||||
}
|
||||
|
||||
func (c *clock) Timer(d time.Duration) *Timer {
|
||||
t := time.NewTimer(d)
|
||||
return &Timer{C: t.C, timer: t}
|
||||
}
|
||||
|
||||
// Mock represents a mock clock that only moves forward programmically.
|
||||
// It can be preferable to a real-time clock when testing time-based functionality.
|
||||
type Mock struct {
|
||||
mu sync.Mutex
|
||||
now time.Time // current time
|
||||
timers clockTimers // tickers & timers
|
||||
|
||||
calls Calls
|
||||
waiting []waiting
|
||||
callsMutex sync.Mutex
|
||||
}
|
||||
|
||||
// NewMock returns an instance of a mock clock.
|
||||
// The current time of the mock clock on initialization is the Unix epoch.
|
||||
func NewMock() *Mock {
|
||||
return &Mock{now: time.Unix(0, 0)}
|
||||
}
|
||||
|
||||
// Add moves the current time of the mock clock forward by the duration.
|
||||
// This should only be called from a single goroutine at a time.
|
||||
func (m *Mock) Add(d time.Duration) {
|
||||
// Calculate the final current time.
|
||||
t := m.now.Add(d)
|
||||
|
||||
// Continue to execute timers until there are no more before the new time.
|
||||
for {
|
||||
if !m.runNextTimer(t) {
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
// Ensure that we end with the new time.
|
||||
m.mu.Lock()
|
||||
m.now = t
|
||||
m.mu.Unlock()
|
||||
|
||||
// Give a small buffer to make sure the other goroutines get handled.
|
||||
gosched()
|
||||
}
|
||||
|
||||
// runNextTimer executes the next timer in chronological order and moves the
|
||||
// current time to the timer's next tick time. The next time is not executed if
|
||||
// it's next time if after the max time. Returns true if a timer is executed.
|
||||
func (m *Mock) runNextTimer(max time.Time) bool {
|
||||
m.mu.Lock()
|
||||
|
||||
// Sort timers by time.
|
||||
sort.Sort(m.timers)
|
||||
|
||||
// If we have no more timers then exit.
|
||||
if len(m.timers) == 0 {
|
||||
m.mu.Unlock()
|
||||
return false
|
||||
}
|
||||
|
||||
// Retrieve next timer. Exit if next tick is after new time.
|
||||
t := m.timers[0]
|
||||
if t.Next().After(max) {
|
||||
m.mu.Unlock()
|
||||
return false
|
||||
}
|
||||
|
||||
// Move "now" forward and unlock clock.
|
||||
m.now = t.Next()
|
||||
m.mu.Unlock()
|
||||
|
||||
// Execute timer.
|
||||
t.Tick(m.now)
|
||||
return true
|
||||
}
|
||||
|
||||
// After waits for the duration to elapse and then sends the current time on the returned channel.
|
||||
func (m *Mock) After(d time.Duration) <-chan time.Time {
|
||||
defer m.inc(&m.calls.After)
|
||||
return m.Timer(d).C
|
||||
}
|
||||
|
||||
// AfterFunc waits for the duration to elapse and then executes a function.
|
||||
// A Timer is returned that can be stopped.
|
||||
func (m *Mock) AfterFunc(d time.Duration, f func()) *Timer {
|
||||
defer m.inc(&m.calls.AfterFunc)
|
||||
t := m.Timer(d)
|
||||
t.C = nil
|
||||
t.fn = f
|
||||
return t
|
||||
}
|
||||
|
||||
// Now returns the current wall time on the mock clock.
|
||||
func (m *Mock) Now() time.Time {
|
||||
defer m.inc(&m.calls.Now)
|
||||
m.mu.Lock()
|
||||
defer m.mu.Unlock()
|
||||
return m.now
|
||||
}
|
||||
|
||||
// Sleep pauses the goroutine for the given duration on the mock clock.
|
||||
// The clock must be moved forward in a separate goroutine.
|
||||
func (m *Mock) Sleep(d time.Duration) {
|
||||
defer m.inc(&m.calls.Sleep)
|
||||
<-m.After(d)
|
||||
}
|
||||
|
||||
// Tick is a convenience function for Ticker().
|
||||
// It will return a ticker channel that cannot be stopped.
|
||||
func (m *Mock) Tick(d time.Duration) <-chan time.Time {
|
||||
defer m.inc(&m.calls.Tick)
|
||||
return m.Ticker(d).C
|
||||
}
|
||||
|
||||
// Ticker creates a new instance of Ticker.
|
||||
func (m *Mock) Ticker(d time.Duration) *Ticker {
|
||||
defer m.inc(&m.calls.Ticker)
|
||||
m.mu.Lock()
|
||||
defer m.mu.Unlock()
|
||||
ch := make(chan time.Time)
|
||||
t := &Ticker{
|
||||
C: ch,
|
||||
c: ch,
|
||||
mock: m,
|
||||
d: d,
|
||||
next: m.now.Add(d),
|
||||
}
|
||||
m.timers = append(m.timers, (*internalTicker)(t))
|
||||
return t
|
||||
}
|
||||
|
||||
// Timer creates a new instance of Timer.
|
||||
func (m *Mock) Timer(d time.Duration) *Timer {
|
||||
defer m.inc(&m.calls.Timer)
|
||||
m.mu.Lock()
|
||||
defer m.mu.Unlock()
|
||||
ch := make(chan time.Time)
|
||||
t := &Timer{
|
||||
C: ch,
|
||||
c: ch,
|
||||
mock: m,
|
||||
next: m.now.Add(d),
|
||||
}
|
||||
m.timers = append(m.timers, (*internalTimer)(t))
|
||||
return t
|
||||
}
|
||||
|
||||
func (m *Mock) removeClockTimer(t clockTimer) {
|
||||
m.mu.Lock()
|
||||
defer m.mu.Unlock()
|
||||
for i, timer := range m.timers {
|
||||
if timer == t {
|
||||
copy(m.timers[i:], m.timers[i+1:])
|
||||
m.timers[len(m.timers)-1] = nil
|
||||
m.timers = m.timers[:len(m.timers)-1]
|
||||
break
|
||||
}
|
||||
}
|
||||
sort.Sort(m.timers)
|
||||
}
|
||||
|
||||
func (m *Mock) inc(addr *uint32) {
|
||||
m.callsMutex.Lock()
|
||||
defer m.callsMutex.Unlock()
|
||||
*addr++
|
||||
var newWaiting []waiting
|
||||
for _, w := range m.waiting {
|
||||
if m.calls.atLeast(w.expected) {
|
||||
close(w.done)
|
||||
continue
|
||||
}
|
||||
newWaiting = append(newWaiting, w)
|
||||
}
|
||||
m.waiting = newWaiting
|
||||
}
|
||||
|
||||
// Wait waits for at least the relevant calls before returning. The expected
|
||||
// Calls are always over the lifetime of the Mock. Values in the Calls struct
|
||||
// are used as the minimum number of calls, this allows you to wait for only
|
||||
// the calls you care about.
|
||||
func (m *Mock) Wait(s Calls) {
|
||||
m.callsMutex.Lock()
|
||||
if m.calls.atLeast(s) {
|
||||
m.callsMutex.Unlock()
|
||||
return
|
||||
}
|
||||
done := make(chan struct{})
|
||||
m.waiting = append(m.waiting, waiting{expected: s, done: done})
|
||||
m.callsMutex.Unlock()
|
||||
<-done
|
||||
}
|
||||
|
||||
// clockTimer represents an object with an associated start time.
|
||||
type clockTimer interface {
|
||||
Next() time.Time
|
||||
Tick(time.Time)
|
||||
}
|
||||
|
||||
// clockTimers represents a list of sortable timers.
|
||||
type clockTimers []clockTimer
|
||||
|
||||
func (a clockTimers) Len() int { return len(a) }
|
||||
func (a clockTimers) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
|
||||
func (a clockTimers) Less(i, j int) bool { return a[i].Next().Before(a[j].Next()) }
|
||||
|
||||
// Timer represents a single event.
|
||||
// The current time will be sent on C, unless the timer was created by AfterFunc.
|
||||
type Timer struct {
|
||||
C <-chan time.Time
|
||||
c chan time.Time
|
||||
timer *time.Timer // realtime impl, if set
|
||||
next time.Time // next tick time
|
||||
mock *Mock // mock clock, if set
|
||||
fn func() // AfterFunc function, if set
|
||||
}
|
||||
|
||||
// Stop turns off the ticker.
|
||||
func (t *Timer) Stop() {
|
||||
if t.timer != nil {
|
||||
t.timer.Stop()
|
||||
} else {
|
||||
t.mock.removeClockTimer((*internalTimer)(t))
|
||||
}
|
||||
}
|
||||
|
||||
type internalTimer Timer
|
||||
|
||||
func (t *internalTimer) Next() time.Time { return t.next }
|
||||
func (t *internalTimer) Tick(now time.Time) {
|
||||
if t.fn != nil {
|
||||
t.fn()
|
||||
} else {
|
||||
t.c <- now
|
||||
}
|
||||
t.mock.removeClockTimer((*internalTimer)(t))
|
||||
gosched()
|
||||
}
|
||||
|
||||
// Ticker holds a channel that receives "ticks" at regular intervals.
|
||||
type Ticker struct {
|
||||
C <-chan time.Time
|
||||
c chan time.Time
|
||||
ticker *time.Ticker // realtime impl, if set
|
||||
next time.Time // next tick time
|
||||
mock *Mock // mock clock, if set
|
||||
d time.Duration // time between ticks
|
||||
}
|
||||
|
||||
// Stop turns off the ticker.
|
||||
func (t *Ticker) Stop() {
|
||||
if t.ticker != nil {
|
||||
t.ticker.Stop()
|
||||
} else {
|
||||
t.mock.removeClockTimer((*internalTicker)(t))
|
||||
}
|
||||
}
|
||||
|
||||
type internalTicker Ticker
|
||||
|
||||
func (t *internalTicker) Next() time.Time { return t.next }
|
||||
func (t *internalTicker) Tick(now time.Time) {
|
||||
select {
|
||||
case t.c <- now:
|
||||
case <-time.After(1 * time.Millisecond):
|
||||
}
|
||||
t.next = now.Add(t.d)
|
||||
gosched()
|
||||
}
|
||||
|
||||
// Sleep momentarily so that other goroutines can process.
|
||||
func gosched() { runtime.Gosched() }
|
||||
|
||||
// Calls keeps track of the count of calls for each of the methods on the Clock
|
||||
// interface.
|
||||
type Calls struct {
|
||||
After uint32
|
||||
AfterFunc uint32
|
||||
Now uint32
|
||||
Sleep uint32
|
||||
Tick uint32
|
||||
Ticker uint32
|
||||
Timer uint32
|
||||
}
|
||||
|
||||
// atLeast returns true if at least the number of calls in o have been made.
|
||||
func (c Calls) atLeast(o Calls) bool {
|
||||
if c.After < o.After {
|
||||
return false
|
||||
}
|
||||
if c.AfterFunc < o.AfterFunc {
|
||||
return false
|
||||
}
|
||||
if c.Now < o.Now {
|
||||
return false
|
||||
}
|
||||
if c.Sleep < o.Sleep {
|
||||
return false
|
||||
}
|
||||
if c.Tick < o.Tick {
|
||||
return false
|
||||
}
|
||||
if c.Ticker < o.Ticker {
|
||||
return false
|
||||
}
|
||||
if c.Timer < o.Timer {
|
||||
return false
|
||||
}
|
||||
return true
|
||||
}
|
||||
|
||||
type waiting struct {
|
||||
expected Calls
|
||||
done chan struct{}
|
||||
}
|
||||
@ -0,0 +1,186 @@
|
||||
// Package gracehttp provides easy to use graceful restart
|
||||
// functionality for HTTP server.
|
||||
package gracehttp
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/tls"
|
||||
"flag"
|
||||
"fmt"
|
||||
"log"
|
||||
"net"
|
||||
"net/http"
|
||||
"os"
|
||||
"os/signal"
|
||||
"sync"
|
||||
"syscall"
|
||||
|
||||
"github.com/facebookgo/grace/gracenet"
|
||||
"github.com/facebookgo/httpdown"
|
||||
)
|
||||
|
||||
var (
|
||||
verbose = flag.Bool("gracehttp.log", true, "Enable logging.")
|
||||
didInherit = os.Getenv("LISTEN_FDS") != ""
|
||||
ppid = os.Getppid()
|
||||
)
|
||||
|
||||
// An app contains one or more servers and associated configuration.
|
||||
type app struct {
|
||||
servers []*http.Server
|
||||
http *httpdown.HTTP
|
||||
net *gracenet.Net
|
||||
listeners []net.Listener
|
||||
sds []httpdown.Server
|
||||
errors chan error
|
||||
}
|
||||
|
||||
func newApp(servers []*http.Server) *app {
|
||||
return &app{
|
||||
servers: servers,
|
||||
http: &httpdown.HTTP{},
|
||||
net: &gracenet.Net{},
|
||||
listeners: make([]net.Listener, 0, len(servers)),
|
||||
sds: make([]httpdown.Server, 0, len(servers)),
|
||||
|
||||
// 2x num servers for possible Close or Stop errors + 1 for possible
|
||||
// StartProcess error.
|
||||
errors: make(chan error, 1+(len(servers)*2)),
|
||||
}
|
||||
}
|
||||
|
||||
func (a *app) listen() error {
|
||||
for _, s := range a.servers {
|
||||
// TODO: default addresses
|
||||
l, err := a.net.Listen("tcp", s.Addr)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if s.TLSConfig != nil {
|
||||
l = tls.NewListener(l, s.TLSConfig)
|
||||
}
|
||||
a.listeners = append(a.listeners, l)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (a *app) serve() {
|
||||
for i, s := range a.servers {
|
||||
a.sds = append(a.sds, a.http.Serve(s, a.listeners[i]))
|
||||
}
|
||||
}
|
||||
|
||||
func (a *app) wait() {
|
||||
var wg sync.WaitGroup
|
||||
wg.Add(len(a.sds) * 2) // Wait & Stop
|
||||
go a.signalHandler(&wg)
|
||||
for _, s := range a.sds {
|
||||
go func(s httpdown.Server) {
|
||||
defer wg.Done()
|
||||
if err := s.Wait(); err != nil {
|
||||
a.errors <- err
|
||||
}
|
||||
}(s)
|
||||
}
|
||||
wg.Wait()
|
||||
}
|
||||
|
||||
func (a *app) term(wg *sync.WaitGroup) {
|
||||
for _, s := range a.sds {
|
||||
go func(s httpdown.Server) {
|
||||
defer wg.Done()
|
||||
if err := s.Stop(); err != nil {
|
||||
a.errors <- err
|
||||
}
|
||||
}(s)
|
||||
}
|
||||
}
|
||||
|
||||
func (a *app) signalHandler(wg *sync.WaitGroup) {
|
||||
ch := make(chan os.Signal, 10)
|
||||
signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM, syscall.SIGUSR2)
|
||||
for {
|
||||
sig := <-ch
|
||||
switch sig {
|
||||
case syscall.SIGINT, syscall.SIGTERM:
|
||||
// this ensures a subsequent INT/TERM will trigger standard go behaviour of
|
||||
// terminating.
|
||||
signal.Stop(ch)
|
||||
a.term(wg)
|
||||
return
|
||||
case syscall.SIGUSR2:
|
||||
// we only return here if there's an error, otherwise the new process
|
||||
// will send us a TERM when it's ready to trigger the actual shutdown.
|
||||
if _, err := a.net.StartProcess(); err != nil {
|
||||
a.errors <- err
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Serve will serve the given http.Servers and will monitor for signals
|
||||
// allowing for graceful termination (SIGTERM) or restart (SIGUSR2).
|
||||
func Serve(servers ...*http.Server) error {
|
||||
a := newApp(servers)
|
||||
|
||||
// Acquire Listeners
|
||||
if err := a.listen(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Some useful logging.
|
||||
if *verbose {
|
||||
if didInherit {
|
||||
if ppid == 1 {
|
||||
log.Printf("Listening on init activated %s", pprintAddr(a.listeners))
|
||||
} else {
|
||||
const msg = "Graceful handoff of %s with new pid %d and old pid %d"
|
||||
log.Printf(msg, pprintAddr(a.listeners), os.Getpid(), ppid)
|
||||
}
|
||||
} else {
|
||||
const msg = "Serving %s with pid %d"
|
||||
log.Printf(msg, pprintAddr(a.listeners), os.Getpid())
|
||||
}
|
||||
}
|
||||
|
||||
// Start serving.
|
||||
a.serve()
|
||||
|
||||
// Close the parent if we inherited and it wasn't init that started us.
|
||||
if didInherit && ppid != 1 {
|
||||
if err := syscall.Kill(ppid, syscall.SIGTERM); err != nil {
|
||||
return fmt.Errorf("failed to close parent: %s", err)
|
||||
}
|
||||
}
|
||||
|
||||
waitdone := make(chan struct{})
|
||||
go func() {
|
||||
defer close(waitdone)
|
||||
a.wait()
|
||||
}()
|
||||
|
||||
select {
|
||||
case err := <-a.errors:
|
||||
if err == nil {
|
||||
panic("unexpected nil error")
|
||||
}
|
||||
return err
|
||||
case <-waitdone:
|
||||
if *verbose {
|
||||
log.Printf("Exiting pid %d.", os.Getpid())
|
||||
}
|
||||
return nil
|
||||
}
|
||||
}
|
||||
|
||||
// Used for pretty printing addresses.
|
||||
func pprintAddr(listeners []net.Listener) []byte {
|
||||
var out bytes.Buffer
|
||||
for i, l := range listeners {
|
||||
if i != 0 {
|
||||
fmt.Fprint(&out, ", ")
|
||||
}
|
||||
fmt.Fprint(&out, l.Addr())
|
||||
}
|
||||
return out.Bytes()
|
||||
}
|
||||
@ -0,0 +1,252 @@
|
||||
// Package gracenet provides a family of Listen functions that either open a
|
||||
// fresh connection or provide an inherited connection from when the process
|
||||
// was started. The behave like their counterparts in the net package, but
|
||||
// transparently provide support for graceful restarts without dropping
|
||||
// connections. This is provided in a systemd socket activation compatible form
|
||||
// to allow using socket activation.
|
||||
//
|
||||
// BUG: Doesn't handle closing of listeners.
|
||||
package gracenet
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"net"
|
||||
"os"
|
||||
"os/exec"
|
||||
"strconv"
|
||||
"strings"
|
||||
"sync"
|
||||
)
|
||||
|
||||
const (
|
||||
// Used to indicate a graceful restart in the new process.
|
||||
envCountKey = "LISTEN_FDS"
|
||||
envCountKeyPrefix = envCountKey + "="
|
||||
)
|
||||
|
||||
// In order to keep the working directory the same as when we started we record
|
||||
// it at startup.
|
||||
var originalWD, _ = os.Getwd()
|
||||
|
||||
// Net provides the family of Listen functions and maintains the associated
|
||||
// state. Typically you will have only once instance of Net per application.
|
||||
type Net struct {
|
||||
inherited []net.Listener
|
||||
active []net.Listener
|
||||
mutex sync.Mutex
|
||||
inheritOnce sync.Once
|
||||
|
||||
// used in tests to override the default behavior of starting from fd 3.
|
||||
fdStart int
|
||||
}
|
||||
|
||||
func (n *Net) inherit() error {
|
||||
var retErr error
|
||||
n.inheritOnce.Do(func() {
|
||||
n.mutex.Lock()
|
||||
defer n.mutex.Unlock()
|
||||
countStr := os.Getenv(envCountKey)
|
||||
if countStr == "" {
|
||||
return
|
||||
}
|
||||
count, err := strconv.Atoi(countStr)
|
||||
if err != nil {
|
||||
retErr = fmt.Errorf("found invalid count value: %s=%s", envCountKey, countStr)
|
||||
return
|
||||
}
|
||||
|
||||
// In tests this may be overridden.
|
||||
fdStart := n.fdStart
|
||||
if fdStart == 0 {
|
||||
// In normal operations if we are inheriting, the listeners will begin at
|
||||
// fd 3.
|
||||
fdStart = 3
|
||||
}
|
||||
|
||||
for i := fdStart; i < fdStart+count; i++ {
|
||||
file := os.NewFile(uintptr(i), "listener")
|
||||
l, err := net.FileListener(file)
|
||||
if err != nil {
|
||||
file.Close()
|
||||
retErr = fmt.Errorf("error inheriting socket fd %d: %s", i, err)
|
||||
return
|
||||
}
|
||||
if err := file.Close(); err != nil {
|
||||
retErr = fmt.Errorf("error closing inherited socket fd %d: %s", i, err)
|
||||
return
|
||||
}
|
||||
n.inherited = append(n.inherited, l)
|
||||
}
|
||||
})
|
||||
return retErr
|
||||
}
|
||||
|
||||
// Listen announces on the local network address laddr. The network net must be
|
||||
// a stream-oriented network: "tcp", "tcp4", "tcp6", "unix" or "unixpacket". It
|
||||
// returns an inherited net.Listener for the matching network and address, or
|
||||
// creates a new one using net.Listen.
|
||||
func (n *Net) Listen(nett, laddr string) (net.Listener, error) {
|
||||
switch nett {
|
||||
default:
|
||||
return nil, net.UnknownNetworkError(nett)
|
||||
case "tcp", "tcp4", "tcp6":
|
||||
addr, err := net.ResolveTCPAddr(nett, laddr)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return n.ListenTCP(nett, addr)
|
||||
case "unix", "unixpacket", "invalid_unix_net_for_test":
|
||||
addr, err := net.ResolveUnixAddr(nett, laddr)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return n.ListenUnix(nett, addr)
|
||||
}
|
||||
}
|
||||
|
||||
// ListenTCP announces on the local network address laddr. The network net must
|
||||
// be: "tcp", "tcp4" or "tcp6". It returns an inherited net.Listener for the
|
||||
// matching network and address, or creates a new one using net.ListenTCP.
|
||||
func (n *Net) ListenTCP(nett string, laddr *net.TCPAddr) (*net.TCPListener, error) {
|
||||
if err := n.inherit(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
n.mutex.Lock()
|
||||
defer n.mutex.Unlock()
|
||||
|
||||
// look for an inherited listener
|
||||
for i, l := range n.inherited {
|
||||
if l == nil { // we nil used inherited listeners
|
||||
continue
|
||||
}
|
||||
if isSameAddr(l.Addr(), laddr) {
|
||||
n.inherited[i] = nil
|
||||
n.active = append(n.active, l)
|
||||
return l.(*net.TCPListener), nil
|
||||
}
|
||||
}
|
||||
|
||||
// make a fresh listener
|
||||
l, err := net.ListenTCP(nett, laddr)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
n.active = append(n.active, l)
|
||||
return l, nil
|
||||
}
|
||||
|
||||
// ListenUnix announces on the local network address laddr. The network net
|
||||
// must be a: "unix" or "unixpacket". It returns an inherited net.Listener for
|
||||
// the matching network and address, or creates a new one using net.ListenUnix.
|
||||
func (n *Net) ListenUnix(nett string, laddr *net.UnixAddr) (*net.UnixListener, error) {
|
||||
if err := n.inherit(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
n.mutex.Lock()
|
||||
defer n.mutex.Unlock()
|
||||
|
||||
// look for an inherited listener
|
||||
for i, l := range n.inherited {
|
||||
if l == nil { // we nil used inherited listeners
|
||||
continue
|
||||
}
|
||||
if isSameAddr(l.Addr(), laddr) {
|
||||
n.inherited[i] = nil
|
||||
n.active = append(n.active, l)
|
||||
return l.(*net.UnixListener), nil
|
||||
}
|
||||
}
|
||||
|
||||
// make a fresh listener
|
||||
l, err := net.ListenUnix(nett, laddr)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
n.active = append(n.active, l)
|
||||
return l, nil
|
||||
}
|
||||
|
||||
// activeListeners returns a snapshot copy of the active listeners.
|
||||
func (n *Net) activeListeners() ([]net.Listener, error) {
|
||||
n.mutex.Lock()
|
||||
defer n.mutex.Unlock()
|
||||
ls := make([]net.Listener, len(n.active))
|
||||
copy(ls, n.active)
|
||||
return ls, nil
|
||||
}
|
||||
|
||||
func isSameAddr(a1, a2 net.Addr) bool {
|
||||
if a1.Network() != a2.Network() {
|
||||
return false
|
||||
}
|
||||
a1s := a1.String()
|
||||
a2s := a2.String()
|
||||
if a1s == a2s {
|
||||
return true
|
||||
}
|
||||
|
||||
// This allows for ipv6 vs ipv4 local addresses to compare as equal. This
|
||||
// scenario is common when listening on localhost.
|
||||
const ipv6prefix = "[::]"
|
||||
a1s = strings.TrimPrefix(a1s, ipv6prefix)
|
||||
a2s = strings.TrimPrefix(a2s, ipv6prefix)
|
||||
const ipv4prefix = "0.0.0.0"
|
||||
a1s = strings.TrimPrefix(a1s, ipv4prefix)
|
||||
a2s = strings.TrimPrefix(a2s, ipv4prefix)
|
||||
return a1s == a2s
|
||||
}
|
||||
|
||||
// StartProcess starts a new process passing it the active listeners. It
|
||||
// doesn't fork, but starts a new process using the same environment and
|
||||
// arguments as when it was originally started. This allows for a newly
|
||||
// deployed binary to be started. It returns the pid of the newly started
|
||||
// process when successful.
|
||||
func (n *Net) StartProcess() (int, error) {
|
||||
listeners, err := n.activeListeners()
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
// Extract the fds from the listeners.
|
||||
files := make([]*os.File, len(listeners))
|
||||
for i, l := range listeners {
|
||||
files[i], err = l.(filer).File()
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
defer files[i].Close()
|
||||
}
|
||||
|
||||
// Use the original binary location. This works with symlinks such that if
|
||||
// the file it points to has been changed we will use the updated symlink.
|
||||
argv0, err := exec.LookPath(os.Args[0])
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
// Pass on the environment and replace the old count key with the new one.
|
||||
var env []string
|
||||
for _, v := range os.Environ() {
|
||||
if !strings.HasPrefix(v, envCountKeyPrefix) {
|
||||
env = append(env, v)
|
||||
}
|
||||
}
|
||||
env = append(env, fmt.Sprintf("%s%d", envCountKeyPrefix, len(listeners)))
|
||||
|
||||
allFiles := append([]*os.File{os.Stdin, os.Stdout, os.Stderr}, files...)
|
||||
process, err := os.StartProcess(argv0, os.Args, &os.ProcAttr{
|
||||
Dir: originalWD,
|
||||
Env: env,
|
||||
Files: allFiles,
|
||||
})
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
return process.Pid, nil
|
||||
}
|
||||
|
||||
type filer interface {
|
||||
File() (*os.File, error)
|
||||
}
|
||||
@ -0,0 +1,30 @@
|
||||
BSD License
|
||||
|
||||
For grace software
|
||||
|
||||
Copyright (c) 2015, Facebook, Inc. 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 Facebook 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.
|
||||
@ -0,0 +1,376 @@
|
||||
// Package httpdown provides http.ConnState enabled graceful termination of
|
||||
// http.Server.
|
||||
package httpdown
|
||||
|
||||
import (
|
||||
"crypto/tls"
|
||||
"fmt"
|
||||
"net"
|
||||
"net/http"
|
||||
"os"
|
||||
"os/signal"
|
||||
"sync"
|
||||
"syscall"
|
||||
"time"
|
||||
|
||||
"github.com/facebookgo/clock"
|
||||
"github.com/facebookgo/stats"
|
||||
)
|
||||
|
||||
const (
|
||||
defaultStopTimeout = time.Minute
|
||||
defaultKillTimeout = time.Minute
|
||||
)
|
||||
|
||||
// A Server allows encapsulates the process of accepting new connections and
|
||||
// serving them, and gracefully shutting down the listener without dropping
|
||||
// active connections.
|
||||
type Server interface {
|
||||
// Wait waits for the serving loop to finish. This will happen when Stop is
|
||||
// called, at which point it returns no error, or if there is an error in the
|
||||
// serving loop. You must call Wait after calling Serve or ListenAndServe.
|
||||
Wait() error
|
||||
|
||||
// Stop stops the listener. It will block until all connections have been
|
||||
// closed.
|
||||
Stop() error
|
||||
}
|
||||
|
||||
// HTTP defines the configuration for serving a http.Server. Multiple calls to
|
||||
// Serve or ListenAndServe can be made on the same HTTP instance. The default
|
||||
// timeouts of 1 minute each result in a maximum of 2 minutes before a Stop()
|
||||
// returns.
|
||||
type HTTP struct {
|
||||
// StopTimeout is the duration before we begin force closing connections.
|
||||
// Defaults to 1 minute.
|
||||
StopTimeout time.Duration
|
||||
|
||||
// KillTimeout is the duration before which we completely give up and abort
|
||||
// even though we still have connected clients. This is useful when a large
|
||||
// number of client connections exist and closing them can take a long time.
|
||||
// Note, this is in addition to the StopTimeout. Defaults to 1 minute.
|
||||
KillTimeout time.Duration
|
||||
|
||||
// Stats is optional. If provided, it will be used to record various metrics.
|
||||
Stats stats.Client
|
||||
|
||||
// Clock allows for testing timing related functionality. Do not specify this
|
||||
// in production code.
|
||||
Clock clock.Clock
|
||||
}
|
||||
|
||||
// Serve provides the low-level API which is useful if you're creating your own
|
||||
// net.Listener.
|
||||
func (h HTTP) Serve(s *http.Server, l net.Listener) Server {
|
||||
stopTimeout := h.StopTimeout
|
||||
if stopTimeout == 0 {
|
||||
stopTimeout = defaultStopTimeout
|
||||
}
|
||||
killTimeout := h.KillTimeout
|
||||
if killTimeout == 0 {
|
||||
killTimeout = defaultKillTimeout
|
||||
}
|
||||
klock := h.Clock
|
||||
if klock == nil {
|
||||
klock = clock.New()
|
||||
}
|
||||
|
||||
ss := &server{
|
||||
stopTimeout: stopTimeout,
|
||||
killTimeout: killTimeout,
|
||||
stats: h.Stats,
|
||||
clock: klock,
|
||||
oldConnState: s.ConnState,
|
||||
listener: l,
|
||||
server: s,
|
||||
serveDone: make(chan struct{}),
|
||||
serveErr: make(chan error, 1),
|
||||
new: make(chan net.Conn),
|
||||
active: make(chan net.Conn),
|
||||
idle: make(chan net.Conn),
|
||||
closed: make(chan net.Conn),
|
||||
stop: make(chan chan struct{}),
|
||||
kill: make(chan chan struct{}),
|
||||
}
|
||||
s.ConnState = ss.connState
|
||||
go ss.manage()
|
||||
go ss.serve()
|
||||
return ss
|
||||
}
|
||||
|
||||
// ListenAndServe returns a Server for the given http.Server. It is equivalent
|
||||
// to ListenAndServe from the standard library, but returns immediately.
|
||||
// Requests will be accepted in a background goroutine. If the http.Server has
|
||||
// a non-nil TLSConfig, a TLS enabled listener will be setup.
|
||||
func (h HTTP) ListenAndServe(s *http.Server) (Server, error) {
|
||||
addr := s.Addr
|
||||
if addr == "" {
|
||||
if s.TLSConfig == nil {
|
||||
addr = ":http"
|
||||
} else {
|
||||
addr = ":https"
|
||||
}
|
||||
}
|
||||
l, err := net.Listen("tcp", addr)
|
||||
if err != nil {
|
||||
stats.BumpSum(h.Stats, "listen.error", 1)
|
||||
return nil, err
|
||||
}
|
||||
if s.TLSConfig != nil {
|
||||
l = tls.NewListener(l, s.TLSConfig)
|
||||
}
|
||||
return h.Serve(s, l), nil
|
||||
}
|
||||
|
||||
// server manages the serving process and allows for gracefully stopping it.
|
||||
type server struct {
|
||||
stopTimeout time.Duration
|
||||
killTimeout time.Duration
|
||||
stats stats.Client
|
||||
clock clock.Clock
|
||||
|
||||
oldConnState func(net.Conn, http.ConnState)
|
||||
server *http.Server
|
||||
serveDone chan struct{}
|
||||
serveErr chan error
|
||||
listener net.Listener
|
||||
|
||||
new chan net.Conn
|
||||
active chan net.Conn
|
||||
idle chan net.Conn
|
||||
closed chan net.Conn
|
||||
stop chan chan struct{}
|
||||
kill chan chan struct{}
|
||||
|
||||
stopOnce sync.Once
|
||||
stopErr error
|
||||
}
|
||||
|
||||
func (s *server) connState(c net.Conn, cs http.ConnState) {
|
||||
if s.oldConnState != nil {
|
||||
s.oldConnState(c, cs)
|
||||
}
|
||||
|
||||
switch cs {
|
||||
case http.StateNew:
|
||||
s.new <- c
|
||||
case http.StateActive:
|
||||
s.active <- c
|
||||
case http.StateIdle:
|
||||
s.idle <- c
|
||||
case http.StateHijacked, http.StateClosed:
|
||||
s.closed <- c
|
||||
}
|
||||
}
|
||||
|
||||
func (s *server) manage() {
|
||||
defer func() {
|
||||
close(s.new)
|
||||
close(s.active)
|
||||
close(s.idle)
|
||||
close(s.closed)
|
||||
close(s.stop)
|
||||
close(s.kill)
|
||||
}()
|
||||
|
||||
var stopDone chan struct{}
|
||||
|
||||
conns := map[net.Conn]http.ConnState{}
|
||||
var countNew, countActive, countIdle float64
|
||||
|
||||
// decConn decrements the count associated with the current state of the
|
||||
// given connection.
|
||||
decConn := func(c net.Conn) {
|
||||
switch conns[c] {
|
||||
default:
|
||||
panic(fmt.Errorf("unknown existing connection: %s", c))
|
||||
case http.StateNew:
|
||||
countNew--
|
||||
case http.StateActive:
|
||||
countActive--
|
||||
case http.StateIdle:
|
||||
countIdle--
|
||||
}
|
||||
}
|
||||
|
||||
// setup a ticker to report various values every minute. if we don't have a
|
||||
// Stats implementation provided, we Stop it so it never ticks.
|
||||
statsTicker := s.clock.Ticker(time.Minute)
|
||||
if s.stats == nil {
|
||||
statsTicker.Stop()
|
||||
}
|
||||
|
||||
for {
|
||||
select {
|
||||
case <-statsTicker.C:
|
||||
// we'll only get here when s.stats is not nil
|
||||
s.stats.BumpAvg("http-state.new", countNew)
|
||||
s.stats.BumpAvg("http-state.active", countActive)
|
||||
s.stats.BumpAvg("http-state.idle", countIdle)
|
||||
s.stats.BumpAvg("http-state.total", countNew+countActive+countIdle)
|
||||
case c := <-s.new:
|
||||
conns[c] = http.StateNew
|
||||
countNew++
|
||||
case c := <-s.active:
|
||||
decConn(c)
|
||||
countActive++
|
||||
|
||||
conns[c] = http.StateActive
|
||||
case c := <-s.idle:
|
||||
decConn(c)
|
||||
countIdle++
|
||||
|
||||
conns[c] = http.StateIdle
|
||||
|
||||
// if we're already stopping, close it
|
||||
if stopDone != nil {
|
||||
c.Close()
|
||||
}
|
||||
case c := <-s.closed:
|
||||
stats.BumpSum(s.stats, "conn.closed", 1)
|
||||
decConn(c)
|
||||
delete(conns, c)
|
||||
|
||||
// if we're waiting to stop and are all empty, we just closed the last
|
||||
// connection and we're done.
|
||||
if stopDone != nil && len(conns) == 0 {
|
||||
close(stopDone)
|
||||
return
|
||||
}
|
||||
case stopDone = <-s.stop:
|
||||
// if we're already all empty, we're already done
|
||||
if len(conns) == 0 {
|
||||
close(stopDone)
|
||||
return
|
||||
}
|
||||
|
||||
// close current idle connections right away
|
||||
for c, cs := range conns {
|
||||
if cs == http.StateIdle {
|
||||
c.Close()
|
||||
}
|
||||
}
|
||||
|
||||
// continue the loop and wait for all the ConnState updates which will
|
||||
// eventually close(stopDone) and return from this goroutine.
|
||||
|
||||
case killDone := <-s.kill:
|
||||
// force close all connections
|
||||
stats.BumpSum(s.stats, "kill.conn.count", float64(len(conns)))
|
||||
for c := range conns {
|
||||
c.Close()
|
||||
}
|
||||
|
||||
// don't block the kill.
|
||||
close(killDone)
|
||||
|
||||
// continue the loop and we wait for all the ConnState updates and will
|
||||
// return from this goroutine when we're all done. otherwise we'll try to
|
||||
// send those ConnState updates on closed channels.
|
||||
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (s *server) serve() {
|
||||
stats.BumpSum(s.stats, "serve", 1)
|
||||
s.serveErr <- s.server.Serve(s.listener)
|
||||
close(s.serveDone)
|
||||
close(s.serveErr)
|
||||
}
|
||||
|
||||
func (s *server) Wait() error {
|
||||
if err := <-s.serveErr; !isUseOfClosedError(err) {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (s *server) Stop() error {
|
||||
s.stopOnce.Do(func() {
|
||||
defer stats.BumpTime(s.stats, "stop.time").End()
|
||||
stats.BumpSum(s.stats, "stop", 1)
|
||||
|
||||
// first disable keep-alive for new connections
|
||||
s.server.SetKeepAlivesEnabled(false)
|
||||
|
||||
// then close the listener so new connections can't connect come thru
|
||||
closeErr := s.listener.Close()
|
||||
<-s.serveDone
|
||||
|
||||
// then trigger the background goroutine to stop and wait for it
|
||||
stopDone := make(chan struct{})
|
||||
s.stop <- stopDone
|
||||
|
||||
// wait for stop
|
||||
select {
|
||||
case <-stopDone:
|
||||
case <-s.clock.After(s.stopTimeout):
|
||||
defer stats.BumpTime(s.stats, "kill.time").End()
|
||||
stats.BumpSum(s.stats, "kill", 1)
|
||||
|
||||
// stop timed out, wait for kill
|
||||
killDone := make(chan struct{})
|
||||
s.kill <- killDone
|
||||
select {
|
||||
case <-killDone:
|
||||
case <-s.clock.After(s.killTimeout):
|
||||
// kill timed out, give up
|
||||
stats.BumpSum(s.stats, "kill.timeout", 1)
|
||||
}
|
||||
}
|
||||
|
||||
if closeErr != nil && !isUseOfClosedError(closeErr) {
|
||||
stats.BumpSum(s.stats, "listener.close.error", 1)
|
||||
s.stopErr = closeErr
|
||||
}
|
||||
})
|
||||
return s.stopErr
|
||||
}
|
||||
|
||||
func isUseOfClosedError(err error) bool {
|
||||
if err == nil {
|
||||
return false
|
||||
}
|
||||
if opErr, ok := err.(*net.OpError); ok {
|
||||
err = opErr.Err
|
||||
}
|
||||
return err.Error() == "use of closed network connection"
|
||||
}
|
||||
|
||||
// ListenAndServe is a convenience function to serve and wait for a SIGTERM
|
||||
// or SIGINT before shutting down.
|
||||
func ListenAndServe(s *http.Server, hd *HTTP) error {
|
||||
if hd == nil {
|
||||
hd = &HTTP{}
|
||||
}
|
||||
hs, err := hd.ListenAndServe(s)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
waiterr := make(chan error, 1)
|
||||
go func() {
|
||||
defer close(waiterr)
|
||||
waiterr <- hs.Wait()
|
||||
}()
|
||||
|
||||
signals := make(chan os.Signal, 10)
|
||||
signal.Notify(signals, syscall.SIGTERM, syscall.SIGINT)
|
||||
|
||||
select {
|
||||
case err := <-waiterr:
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
case <-signals:
|
||||
signal.Stop(signals)
|
||||
if err := hs.Stop(); err != nil {
|
||||
return err
|
||||
}
|
||||
if err := <-waiterr; err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
@ -0,0 +1,30 @@
|
||||
BSD License
|
||||
|
||||
For httpdown software
|
||||
|
||||
Copyright (c) 2015, Facebook, Inc. 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 Facebook 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.
|
||||
@ -0,0 +1,41 @@
|
||||
httpdown [](https://travis-ci.org/facebookgo/httpdown)
|
||||
========
|
||||
|
||||
Documentation: https://godoc.org/github.com/facebookgo/httpdown
|
||||
|
||||
Package httpdown provides a library that makes it easy to build a HTTP server
|
||||
that can be shutdown gracefully (that is, without dropping any connections).
|
||||
|
||||
If you want graceful restart and not just graceful shutdown, look at the
|
||||
[grace](https://github.com/facebookgo/grace) package which uses this package
|
||||
underneath but also provides graceful restart.
|
||||
|
||||
Usage
|
||||
-----
|
||||
|
||||
Demo HTTP Server with graceful termination:
|
||||
https://github.com/facebookgo/httpdown/blob/master/httpdown_example/main.go
|
||||
|
||||
1. Install the demo application
|
||||
|
||||
go get github.com/facebookgo/httpdown/httpdown_example
|
||||
|
||||
1. Start it in the first terminal
|
||||
|
||||
httpdown_example
|
||||
|
||||
This will output something like:
|
||||
|
||||
2014/11/18 21:57:50 serving on http://127.0.0.1:8080/ with pid 17
|
||||
|
||||
1. In a second terminal start a slow HTTP request
|
||||
|
||||
curl 'http://localhost:8080/?duration=20s'
|
||||
|
||||
1. In a third terminal trigger a graceful shutdown (using the pid from your output):
|
||||
|
||||
kill -TERM 17
|
||||
|
||||
This will demonstrate that the slow request was served before the server was
|
||||
shutdown. You could also have used `Ctrl-C` instead of `kill` as the example
|
||||
application triggers graceful shutdown on TERM or INT signals.
|
||||
@ -0,0 +1,35 @@
|
||||
package stats
|
||||
|
||||
import "sort"
|
||||
|
||||
// Average returns the average value
|
||||
func Average(values []float64) float64 {
|
||||
if len(values) == 0 {
|
||||
return 0
|
||||
}
|
||||
|
||||
var val float64
|
||||
for _, point := range values {
|
||||
val += point
|
||||
}
|
||||
return val / float64(len(values))
|
||||
}
|
||||
|
||||
// Sum returns the sum of all the given values
|
||||
func Sum(values []float64) float64 {
|
||||
var val float64
|
||||
for _, point := range values {
|
||||
val += point
|
||||
}
|
||||
return val
|
||||
}
|
||||
|
||||
// Percentiles returns a map containing the asked for percentiles
|
||||
func Percentiles(values []float64, percentiles map[string]float64) map[string]float64 {
|
||||
sort.Float64s(values)
|
||||
results := map[string]float64{}
|
||||
for label, p := range percentiles {
|
||||
results[label] = values[int(float64(len(values))*p)]
|
||||
}
|
||||
return results
|
||||
}
|
||||
@ -0,0 +1,112 @@
|
||||
package stats
|
||||
|
||||
import "fmt"
|
||||
|
||||
// Type is the type of aggregation of apply
|
||||
type Type int
|
||||
|
||||
const (
|
||||
AggregateAvg Type = iota
|
||||
AggregateSum
|
||||
AggregateHistogram
|
||||
)
|
||||
|
||||
var (
|
||||
// HistogramPercentiles is used to determine which percentiles to return for
|
||||
// SimpleCounter.Aggregate
|
||||
HistogramPercentiles = map[string]float64{
|
||||
"p50": 0.5,
|
||||
"p95": 0.95,
|
||||
"p99": 0.99,
|
||||
}
|
||||
|
||||
// MinSamplesForPercentiles is used by SimpleCounter.Aggregate to determine
|
||||
// what the minimum number of samples is required for percentile analysis
|
||||
MinSamplesForPercentiles = 10
|
||||
)
|
||||
|
||||
// Aggregates can be used to merge counters together. This is not goroutine safe
|
||||
type Aggregates map[string]Counter
|
||||
|
||||
// Add adds the counter for aggregation. This is not goroutine safe
|
||||
func (a Aggregates) Add(c Counter) error {
|
||||
key := c.FullKey()
|
||||
if counter, ok := a[key]; ok {
|
||||
if counter.GetType() != c.GetType() {
|
||||
return fmt.Errorf("stats: mismatched aggregation type for: %s", key)
|
||||
}
|
||||
counter.AddValues(c.GetValues()...)
|
||||
} else {
|
||||
a[key] = c
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Counter is the interface used by Aggregates to merge counters together
|
||||
type Counter interface {
|
||||
// FullKey is used to uniquely identify the counter
|
||||
FullKey() string
|
||||
|
||||
// AddValues adds values for aggregation
|
||||
AddValues(...float64)
|
||||
|
||||
// GetValues returns the values for aggregation
|
||||
GetValues() []float64
|
||||
|
||||
// GetType returns the type of aggregation to apply
|
||||
GetType() Type
|
||||
}
|
||||
|
||||
// SimpleCounter is a basic implementation of the Counter interface
|
||||
type SimpleCounter struct {
|
||||
Key string
|
||||
Values []float64
|
||||
Type Type
|
||||
}
|
||||
|
||||
// FullKey is part of the Counter interace
|
||||
func (s *SimpleCounter) FullKey() string {
|
||||
return s.Key
|
||||
}
|
||||
|
||||
// GetValues is part of the Counter interface
|
||||
func (s *SimpleCounter) GetValues() []float64 {
|
||||
return s.Values
|
||||
}
|
||||
|
||||
// AddValues is part of the Counter interface
|
||||
func (s *SimpleCounter) AddValues(vs ...float64) {
|
||||
s.Values = append(s.Values, vs...)
|
||||
}
|
||||
|
||||
// GetType is part of the Counter interface
|
||||
func (s *SimpleCounter) GetType() Type {
|
||||
return s.Type
|
||||
}
|
||||
|
||||
// Aggregate aggregates the provided values appropriately, returning a map
|
||||
// from key to value. If AggregateHistogram is specified, the map will contain
|
||||
// the relevant percentiles as specified by HistogramPercentiles
|
||||
func (s *SimpleCounter) Aggregate() map[string]float64 {
|
||||
switch s.Type {
|
||||
case AggregateAvg:
|
||||
return map[string]float64{
|
||||
s.Key: Average(s.Values),
|
||||
}
|
||||
case AggregateSum:
|
||||
return map[string]float64{
|
||||
s.Key: Sum(s.Values),
|
||||
}
|
||||
case AggregateHistogram:
|
||||
histogram := map[string]float64{
|
||||
s.Key: Average(s.Values),
|
||||
}
|
||||
if len(s.Values) > MinSamplesForPercentiles {
|
||||
for k, v := range Percentiles(s.Values, HistogramPercentiles) {
|
||||
histogram[fmt.Sprintf("%s.%s", s.Key, k)] = v
|
||||
}
|
||||
}
|
||||
return histogram
|
||||
}
|
||||
panic("stats: unsupported aggregation type")
|
||||
}
|
||||
@ -0,0 +1,30 @@
|
||||
BSD License
|
||||
|
||||
For stats software
|
||||
|
||||
Copyright (c) 2015, Facebook, Inc. 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 Facebook 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.
|
||||
@ -0,0 +1,4 @@
|
||||
stats [](https://travis-ci.org/facebookgo/stats)
|
||||
=====
|
||||
|
||||
Documentation: https://godoc.org/github.com/facebookgo/stats
|
||||
@ -0,0 +1,166 @@
|
||||
// Package stats defines a lightweight interface for collecting statistics. It
|
||||
// doesn't provide an implementation, just the shared interface.
|
||||
package stats
|
||||
|
||||
// Client provides methods to collection statistics.
|
||||
type Client interface {
|
||||
// BumpAvg bumps the average for the given key.
|
||||
BumpAvg(key string, val float64)
|
||||
|
||||
// BumpSum bumps the sum for the given key.
|
||||
BumpSum(key string, val float64)
|
||||
|
||||
// BumpHistogram bumps the histogram for the given key.
|
||||
BumpHistogram(key string, val float64)
|
||||
|
||||
// BumpTime is a special version of BumpHistogram which is specialized for
|
||||
// timers. Calling it starts the timer, and it returns a value on which End()
|
||||
// can be called to indicate finishing the timer. A convenient way of
|
||||
// recording the duration of a function is calling it like such at the top of
|
||||
// the function:
|
||||
//
|
||||
// defer s.BumpTime("my.function").End()
|
||||
BumpTime(key string) interface {
|
||||
End()
|
||||
}
|
||||
}
|
||||
|
||||
// PrefixClient adds multiple keys for the same value, with each prefix
|
||||
// added to the key and calls the underlying client.
|
||||
func PrefixClient(prefixes []string, client Client) Client {
|
||||
return &prefixClient{
|
||||
Prefixes: prefixes,
|
||||
Client: client,
|
||||
}
|
||||
}
|
||||
|
||||
type prefixClient struct {
|
||||
Prefixes []string
|
||||
Client Client
|
||||
}
|
||||
|
||||
func (p *prefixClient) BumpAvg(key string, val float64) {
|
||||
for _, prefix := range p.Prefixes {
|
||||
p.Client.BumpAvg(prefix+key, val)
|
||||
}
|
||||
}
|
||||
|
||||
func (p *prefixClient) BumpSum(key string, val float64) {
|
||||
for _, prefix := range p.Prefixes {
|
||||
p.Client.BumpSum(prefix+key, val)
|
||||
}
|
||||
}
|
||||
|
||||
func (p *prefixClient) BumpHistogram(key string, val float64) {
|
||||
for _, prefix := range p.Prefixes {
|
||||
p.Client.BumpHistogram(prefix+key, val)
|
||||
}
|
||||
}
|
||||
|
||||
func (p *prefixClient) BumpTime(key string) interface {
|
||||
End()
|
||||
} {
|
||||
var m multiEnder
|
||||
for _, prefix := range p.Prefixes {
|
||||
m = append(m, p.Client.BumpTime(prefix+key))
|
||||
}
|
||||
return m
|
||||
}
|
||||
|
||||
// multiEnder combines many enders together.
|
||||
type multiEnder []interface {
|
||||
End()
|
||||
}
|
||||
|
||||
func (m multiEnder) End() {
|
||||
for _, e := range m {
|
||||
e.End()
|
||||
}
|
||||
}
|
||||
|
||||
// HookClient is useful for testing. It provides optional hooks for each
|
||||
// expected method in the interface, which if provided will be called. If a
|
||||
// hook is not provided, it will be ignored.
|
||||
type HookClient struct {
|
||||
BumpAvgHook func(key string, val float64)
|
||||
BumpSumHook func(key string, val float64)
|
||||
BumpHistogramHook func(key string, val float64)
|
||||
BumpTimeHook func(key string) interface {
|
||||
End()
|
||||
}
|
||||
}
|
||||
|
||||
// BumpAvg will call BumpAvgHook if defined.
|
||||
func (c *HookClient) BumpAvg(key string, val float64) {
|
||||
if c.BumpAvgHook != nil {
|
||||
c.BumpAvgHook(key, val)
|
||||
}
|
||||
}
|
||||
|
||||
// BumpSum will call BumpSumHook if defined.
|
||||
func (c *HookClient) BumpSum(key string, val float64) {
|
||||
if c.BumpSumHook != nil {
|
||||
c.BumpSumHook(key, val)
|
||||
}
|
||||
}
|
||||
|
||||
// BumpHistogram will call BumpHistogramHook if defined.
|
||||
func (c *HookClient) BumpHistogram(key string, val float64) {
|
||||
if c.BumpHistogramHook != nil {
|
||||
c.BumpHistogramHook(key, val)
|
||||
}
|
||||
}
|
||||
|
||||
// BumpTime will call BumpTimeHook if defined.
|
||||
func (c *HookClient) BumpTime(key string) interface {
|
||||
End()
|
||||
} {
|
||||
if c.BumpTimeHook != nil {
|
||||
return c.BumpTimeHook(key)
|
||||
}
|
||||
return NoOpEnd
|
||||
}
|
||||
|
||||
type noOpEnd struct{}
|
||||
|
||||
func (n noOpEnd) End() {}
|
||||
|
||||
// NoOpEnd provides a dummy value for use in tests as valid return value for
|
||||
// BumpTime().
|
||||
var NoOpEnd = noOpEnd{}
|
||||
|
||||
// BumpAvg calls BumpAvg on the Client if it isn't nil. This is useful when a
|
||||
// component has an optional stats.Client.
|
||||
func BumpAvg(c Client, key string, val float64) {
|
||||
if c != nil {
|
||||
c.BumpAvg(key, val)
|
||||
}
|
||||
}
|
||||
|
||||
// BumpSum calls BumpSum on the Client if it isn't nil. This is useful when a
|
||||
// component has an optional stats.Client.
|
||||
func BumpSum(c Client, key string, val float64) {
|
||||
if c != nil {
|
||||
c.BumpSum(key, val)
|
||||
}
|
||||
}
|
||||
|
||||
// BumpHistogram calls BumpHistogram on the Client if it isn't nil. This is
|
||||
// useful when a component has an optional stats.Client.
|
||||
func BumpHistogram(c Client, key string, val float64) {
|
||||
if c != nil {
|
||||
c.BumpHistogram(key, val)
|
||||
}
|
||||
}
|
||||
|
||||
// BumpTime calls BumpTime on the Client if it isn't nil. If the Client is nil
|
||||
// it still returns a valid return value which will be a no-op. This is useful
|
||||
// when a component has an optional stats.Client.
|
||||
func BumpTime(c Client, key string) interface {
|
||||
End()
|
||||
} {
|
||||
if c != nil {
|
||||
return c.BumpTime(key)
|
||||
}
|
||||
return NoOpEnd
|
||||
}
|
||||
@ -0,0 +1,17 @@
|
||||
package stats
|
||||
|
||||
import "time"
|
||||
|
||||
// Stopper calls Client.BumpSum and Client.BumpHistogram when End'ed
|
||||
type Stopper struct {
|
||||
Key string
|
||||
Start time.Time
|
||||
Client Client
|
||||
}
|
||||
|
||||
// End the Stopper
|
||||
func (s *Stopper) End() {
|
||||
since := time.Since(s.Start).Seconds() * 1000.0
|
||||
s.Client.BumpSum(s.Key+".total", since)
|
||||
s.Client.BumpHistogram(s.Key, since)
|
||||
}
|
||||
Loading…
Reference in new issue