progress: add terminal size detection
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>docker-18.09
parent
376ac07c8d
commit
c654d03037
|
@ -3,6 +3,7 @@ package progressui
|
|||
import (
|
||||
"context"
|
||||
"fmt"
|
||||
"os"
|
||||
"time"
|
||||
|
||||
"github.com/containerd/console"
|
||||
|
@ -10,15 +11,22 @@ import (
|
|||
"github.com/morikuni/aec"
|
||||
digest "github.com/opencontainers/go-digest"
|
||||
"github.com/tonistiigi/buildkit_poc/client"
|
||||
"golang.org/x/time/rate"
|
||||
)
|
||||
|
||||
func DisplaySolveStatus(ctx context.Context, ch chan *client.SolveStatus) error {
|
||||
disp := &display{c: console.Current()}
|
||||
c, err := console.ConsoleFromFile(os.Stdout)
|
||||
if err != nil {
|
||||
return err // TODO: switch to log mode
|
||||
}
|
||||
disp := &display{c: c}
|
||||
|
||||
t := newTrace()
|
||||
ticker := time.NewTicker(100 * time.Millisecond)
|
||||
defer ticker.Stop()
|
||||
|
||||
displayLimiter := rate.NewLimiter(rate.Every(50*time.Millisecond), 1)
|
||||
|
||||
var done bool
|
||||
|
||||
for {
|
||||
|
@ -28,14 +36,17 @@ func DisplaySolveStatus(ctx context.Context, ch chan *client.SolveStatus) error
|
|||
case <-ticker.C:
|
||||
case ss, ok := <-ch:
|
||||
if ok {
|
||||
t.update(ss) // rate limit
|
||||
t.update(ss)
|
||||
} else {
|
||||
done = true
|
||||
}
|
||||
}
|
||||
disp.print(t.displayInfo(-1))
|
||||
|
||||
if done {
|
||||
disp.print(t.displayInfo(), true)
|
||||
return nil
|
||||
} else if displayLimiter.Allow() {
|
||||
disp.print(t.displayInfo(), false)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
@ -51,6 +62,7 @@ type job struct {
|
|||
startTime *time.Time
|
||||
completedTime *time.Time
|
||||
name string
|
||||
status string
|
||||
}
|
||||
|
||||
type trace struct {
|
||||
|
@ -107,7 +119,7 @@ func (t *trace) update(s *client.SolveStatus) {
|
|||
}
|
||||
}
|
||||
|
||||
func (t *trace) displayInfo(maxRows int) (d displayInfo) {
|
||||
func (t *trace) displayInfo() (d displayInfo) {
|
||||
d.startTime = time.Now()
|
||||
if t.localTimeDiff != 0 {
|
||||
d.startTime = (*t.vertexes[0].Started).Add(t.localTimeDiff)
|
||||
|
@ -133,7 +145,7 @@ func (t *trace) displayInfo(maxRows int) (d displayInfo) {
|
|||
name: "=> " + s.ID,
|
||||
}
|
||||
if s.Total != 0 {
|
||||
j.name += " " + units.HumanSize(float64(s.Current)) + " / " + units.HumanSize(float64(s.Total))
|
||||
j.status = units.HumanSize(float64(s.Current)) + " / " + units.HumanSize(float64(s.Total))
|
||||
}
|
||||
d.jobs = append(d.jobs, j)
|
||||
}
|
||||
|
@ -156,13 +168,19 @@ type display struct {
|
|||
repeated bool
|
||||
}
|
||||
|
||||
func (disp *display) print(d displayInfo) {
|
||||
width := 60
|
||||
func (disp *display) print(d displayInfo, all bool) {
|
||||
// this output is inspired by Buck
|
||||
width := 80
|
||||
height := 10
|
||||
size, err := disp.c.Size()
|
||||
if err == nil {
|
||||
width = int(size.Width)
|
||||
height = int(size.Height)
|
||||
}
|
||||
|
||||
if !all {
|
||||
d.jobs = wrapHeight(d.jobs, height-2)
|
||||
}
|
||||
_ = width
|
||||
|
||||
b := aec.EmptyBuilder
|
||||
for i := 0; i <= disp.lineCount; i++ {
|
||||
|
@ -181,6 +199,7 @@ func (disp *display) print(d displayInfo) {
|
|||
}
|
||||
|
||||
fmt.Printf("[+] Building %.1fs (%d/%d) %s\n", time.Since(d.startTime).Seconds(), d.countCompleted, d.countTotal, statusStr)
|
||||
lineCount := 0
|
||||
for _, j := range d.jobs {
|
||||
endTime := time.Now()
|
||||
if j.completedTime != nil {
|
||||
|
@ -190,11 +209,43 @@ func (disp *display) print(d displayInfo) {
|
|||
if dt < 0.05 {
|
||||
dt = 0
|
||||
}
|
||||
out := fmt.Sprintf(" => %s %.1fs\n", j.name, dt)
|
||||
pfx := " => "
|
||||
timer := fmt.Sprintf(" %.1fs\n", dt)
|
||||
status := j.status
|
||||
showStatus := false
|
||||
|
||||
left := width - len(pfx) - len(timer) - 1
|
||||
if status != "" {
|
||||
if left+len(status) > 20 {
|
||||
showStatus = true
|
||||
left -= len(status) + 1
|
||||
}
|
||||
}
|
||||
if left < 12 { // too small screen to show progress
|
||||
continue
|
||||
}
|
||||
if len(j.name) > left {
|
||||
j.name = j.name[:left]
|
||||
}
|
||||
|
||||
out := pfx + j.name
|
||||
if showStatus {
|
||||
out += " " + status
|
||||
}
|
||||
|
||||
out = fmt.Sprintf("%-[2]*[1]s %[3]s", out, width-len(timer)-1, timer)
|
||||
if j.completedTime != nil {
|
||||
out = aec.Apply(out, aec.BlueF)
|
||||
}
|
||||
fmt.Print(out)
|
||||
lineCount++
|
||||
}
|
||||
disp.lineCount = len(d.jobs)
|
||||
disp.lineCount = lineCount
|
||||
}
|
||||
|
||||
func wrapHeight(j []job, limit int) []job {
|
||||
if len(j) > limit {
|
||||
j = j[len(j)-limit:]
|
||||
}
|
||||
return j
|
||||
}
|
||||
|
|
|
@ -28,4 +28,5 @@ golang.org/x/text 19e51611da83d6be54ddafce4a4af510cb3e9ea4
|
|||
|
||||
github.com/urfave/cli d70f47eeca3afd795160003bc6e28b001d60c67c
|
||||
github.com/docker/go-units 0dadbb0345b35ec7ef35e228dabb8de89a65bf52
|
||||
github.com/google/shlex 6f45313302b9c56850fc17f99e40caebce98c716
|
||||
github.com/google/shlex 6f45313302b9c56850fc17f99e40caebce98c716
|
||||
golang.org/x/time 8be79e1e0910c292df4e79c241bb7e8f7e725959
|
|
@ -0,0 +1,27 @@
|
|||
Copyright (c) 2009 The Go Authors. 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 Google Inc. 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
|
||||
OWNER 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 +1,22 @@
|
|||
Additional IP Rights Grant (Patents)
|
||||
|
||||
"This implementation" means the copyrightable works distributed by
|
||||
Google as part of the Go project.
|
||||
|
||||
Google hereby grants to You a perpetual, worldwide, non-exclusive,
|
||||
no-charge, royalty-free, irrevocable (except as stated in this section)
|
||||
patent license to make, have made, use, offer to sell, sell, import,
|
||||
transfer and otherwise run, modify and propagate the contents of this
|
||||
implementation of Go, where such license applies only to those patent
|
||||
claims, both currently owned or controlled by Google and acquired in
|
||||
the future, licensable by Google that are necessarily infringed by this
|
||||
implementation of Go. This grant does not include claims that would be
|
||||
infringed only as a consequence of further modification of this
|
||||
implementation. If you or your agent or exclusive licensee institute or
|
||||
order or agree to the institution of patent litigation against any
|
||||
entity (including a cross-claim or counterclaim in a lawsuit) alleging
|
||||
that this implementation of Go or any code incorporated within this
|
||||
implementation of Go constitutes direct or contributory patent
|
||||
infringement, or inducement of patent infringement, then any patent
|
||||
rights granted to you under this License for this implementation of Go
|
||||
shall terminate as of the date such litigation is filed.
|
|
@ -0,0 +1 @@
|
|||
This repository provides supplementary Go time packages.
|
|
@ -0,0 +1,380 @@
|
|||
// Copyright 2015 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// Package rate provides a rate limiter.
|
||||
package rate
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"math"
|
||||
"sync"
|
||||
"time"
|
||||
)
|
||||
|
||||
// Limit defines the maximum frequency of some events.
|
||||
// Limit is represented as number of events per second.
|
||||
// A zero Limit allows no events.
|
||||
type Limit float64
|
||||
|
||||
// Inf is the infinite rate limit; it allows all events (even if burst is zero).
|
||||
const Inf = Limit(math.MaxFloat64)
|
||||
|
||||
// Every converts a minimum time interval between events to a Limit.
|
||||
func Every(interval time.Duration) Limit {
|
||||
if interval <= 0 {
|
||||
return Inf
|
||||
}
|
||||
return 1 / Limit(interval.Seconds())
|
||||
}
|
||||
|
||||
// A Limiter controls how frequently events are allowed to happen.
|
||||
// It implements a "token bucket" of size b, initially full and refilled
|
||||
// at rate r tokens per second.
|
||||
// Informally, in any large enough time interval, the Limiter limits the
|
||||
// rate to r tokens per second, with a maximum burst size of b events.
|
||||
// As a special case, if r == Inf (the infinite rate), b is ignored.
|
||||
// See https://en.wikipedia.org/wiki/Token_bucket for more about token buckets.
|
||||
//
|
||||
// The zero value is a valid Limiter, but it will reject all events.
|
||||
// Use NewLimiter to create non-zero Limiters.
|
||||
//
|
||||
// Limiter has three main methods, Allow, Reserve, and Wait.
|
||||
// Most callers should use Wait.
|
||||
//
|
||||
// Each of the three methods consumes a single token.
|
||||
// They differ in their behavior when no token is available.
|
||||
// If no token is available, Allow returns false.
|
||||
// If no token is available, Reserve returns a reservation for a future token
|
||||
// and the amount of time the caller must wait before using it.
|
||||
// If no token is available, Wait blocks until one can be obtained
|
||||
// or its associated context.Context is canceled.
|
||||
//
|
||||
// The methods AllowN, ReserveN, and WaitN consume n tokens.
|
||||
type Limiter struct {
|
||||
limit Limit
|
||||
burst int
|
||||
|
||||
mu sync.Mutex
|
||||
tokens float64
|
||||
// last is the last time the limiter's tokens field was updated
|
||||
last time.Time
|
||||
// lastEvent is the latest time of a rate-limited event (past or future)
|
||||
lastEvent time.Time
|
||||
}
|
||||
|
||||
// Limit returns the maximum overall event rate.
|
||||
func (lim *Limiter) Limit() Limit {
|
||||
lim.mu.Lock()
|
||||
defer lim.mu.Unlock()
|
||||
return lim.limit
|
||||
}
|
||||
|
||||
// Burst returns the maximum burst size. Burst is the maximum number of tokens
|
||||
// that can be consumed in a single call to Allow, Reserve, or Wait, so higher
|
||||
// Burst values allow more events to happen at once.
|
||||
// A zero Burst allows no events, unless limit == Inf.
|
||||
func (lim *Limiter) Burst() int {
|
||||
return lim.burst
|
||||
}
|
||||
|
||||
// NewLimiter returns a new Limiter that allows events up to rate r and permits
|
||||
// bursts of at most b tokens.
|
||||
func NewLimiter(r Limit, b int) *Limiter {
|
||||
return &Limiter{
|
||||
limit: r,
|
||||
burst: b,
|
||||
}
|
||||
}
|
||||
|
||||
// Allow is shorthand for AllowN(time.Now(), 1).
|
||||
func (lim *Limiter) Allow() bool {
|
||||
return lim.AllowN(time.Now(), 1)
|
||||
}
|
||||
|
||||
// AllowN reports whether n events may happen at time now.
|
||||
// Use this method if you intend to drop / skip events that exceed the rate limit.
|
||||
// Otherwise use Reserve or Wait.
|
||||
func (lim *Limiter) AllowN(now time.Time, n int) bool {
|
||||
return lim.reserveN(now, n, 0).ok
|
||||
}
|
||||
|
||||
// A Reservation holds information about events that are permitted by a Limiter to happen after a delay.
|
||||
// A Reservation may be canceled, which may enable the Limiter to permit additional events.
|
||||
type Reservation struct {
|
||||
ok bool
|
||||
lim *Limiter
|
||||
tokens int
|
||||
timeToAct time.Time
|
||||
// This is the Limit at reservation time, it can change later.
|
||||
limit Limit
|
||||
}
|
||||
|
||||
// OK returns whether the limiter can provide the requested number of tokens
|
||||
// within the maximum wait time. If OK is false, Delay returns InfDuration, and
|
||||
// Cancel does nothing.
|
||||
func (r *Reservation) OK() bool {
|
||||
return r.ok
|
||||
}
|
||||
|
||||
// Delay is shorthand for DelayFrom(time.Now()).
|
||||
func (r *Reservation) Delay() time.Duration {
|
||||
return r.DelayFrom(time.Now())
|
||||
}
|
||||
|
||||
// InfDuration is the duration returned by Delay when a Reservation is not OK.
|
||||
const InfDuration = time.Duration(1<<63 - 1)
|
||||
|
||||
// DelayFrom returns the duration for which the reservation holder must wait
|
||||
// before taking the reserved action. Zero duration means act immediately.
|
||||
// InfDuration means the limiter cannot grant the tokens requested in this
|
||||
// Reservation within the maximum wait time.
|
||||
func (r *Reservation) DelayFrom(now time.Time) time.Duration {
|
||||
if !r.ok {
|
||||
return InfDuration
|
||||
}
|
||||
delay := r.timeToAct.Sub(now)
|
||||
if delay < 0 {
|
||||
return 0
|
||||
}
|
||||
return delay
|
||||
}
|
||||
|
||||
// Cancel is shorthand for CancelAt(time.Now()).
|
||||
func (r *Reservation) Cancel() {
|
||||
r.CancelAt(time.Now())
|
||||
return
|
||||
}
|
||||
|
||||
// CancelAt indicates that the reservation holder will not perform the reserved action
|
||||
// and reverses the effects of this Reservation on the rate limit as much as possible,
|
||||
// considering that other reservations may have already been made.
|
||||
func (r *Reservation) CancelAt(now time.Time) {
|
||||
if !r.ok {
|
||||
return
|
||||
}
|
||||
|
||||
r.lim.mu.Lock()
|
||||
defer r.lim.mu.Unlock()
|
||||
|
||||
if r.lim.limit == Inf || r.tokens == 0 || r.timeToAct.Before(now) {
|
||||
return
|
||||
}
|
||||
|
||||
// calculate tokens to restore
|
||||
// The duration between lim.lastEvent and r.timeToAct tells us how many tokens were reserved
|
||||
// after r was obtained. These tokens should not be restored.
|
||||
restoreTokens := float64(r.tokens) - r.limit.tokensFromDuration(r.lim.lastEvent.Sub(r.timeToAct))
|
||||
if restoreTokens <= 0 {
|
||||
return
|
||||
}
|
||||
// advance time to now
|
||||
now, _, tokens := r.lim.advance(now)
|
||||
// calculate new number of tokens
|
||||
tokens += restoreTokens
|
||||
if burst := float64(r.lim.burst); tokens > burst {
|
||||
tokens = burst
|
||||
}
|
||||
// update state
|
||||
r.lim.last = now
|
||||
r.lim.tokens = tokens
|
||||
if r.timeToAct == r.lim.lastEvent {
|
||||
prevEvent := r.timeToAct.Add(r.limit.durationFromTokens(float64(-r.tokens)))
|
||||
if !prevEvent.Before(now) {
|
||||
r.lim.lastEvent = prevEvent
|
||||
}
|
||||
}
|
||||
|
||||
return
|
||||
}
|
||||
|
||||
// Reserve is shorthand for ReserveN(time.Now(), 1).
|
||||
func (lim *Limiter) Reserve() *Reservation {
|
||||
return lim.ReserveN(time.Now(), 1)
|
||||
}
|
||||
|
||||
// ReserveN returns a Reservation that indicates how long the caller must wait before n events happen.
|
||||
// The Limiter takes this Reservation into account when allowing future events.
|
||||
// ReserveN returns false if n exceeds the Limiter's burst size.
|
||||
// Usage example:
|
||||
// r := lim.ReserveN(time.Now(), 1)
|
||||
// if !r.OK() {
|
||||
// // Not allowed to act! Did you remember to set lim.burst to be > 0 ?
|
||||
// return
|
||||
// }
|
||||
// time.Sleep(r.Delay())
|
||||
// Act()
|
||||
// Use this method if you wish to wait and slow down in accordance with the rate limit without dropping events.
|
||||
// If you need to respect a deadline or cancel the delay, use Wait instead.
|
||||
// To drop or skip events exceeding rate limit, use Allow instead.
|
||||
func (lim *Limiter) ReserveN(now time.Time, n int) *Reservation {
|
||||
r := lim.reserveN(now, n, InfDuration)
|
||||
return &r
|
||||
}
|
||||
|
||||
// contextContext is a temporary(?) copy of the context.Context type
|
||||
// to support both Go 1.6 using golang.org/x/net/context and Go 1.7+
|
||||
// with the built-in context package. If people ever stop using Go 1.6
|
||||
// we can remove this.
|
||||
type contextContext interface {
|
||||
Deadline() (deadline time.Time, ok bool)
|
||||
Done() <-chan struct{}
|
||||
Err() error
|
||||
Value(key interface{}) interface{}
|
||||
}
|
||||
|
||||
// Wait is shorthand for WaitN(ctx, 1).
|
||||
func (lim *Limiter) wait(ctx contextContext) (err error) {
|
||||
return lim.WaitN(ctx, 1)
|
||||
}
|
||||
|
||||
// WaitN blocks until lim permits n events to happen.
|
||||
// It returns an error if n exceeds the Limiter's burst size, the Context is
|
||||
// canceled, or the expected wait time exceeds the Context's Deadline.
|
||||
// The burst limit is ignored if the rate limit is Inf.
|
||||
func (lim *Limiter) waitN(ctx contextContext, n int) (err error) {
|
||||
if n > lim.burst && lim.limit != Inf {
|
||||
return fmt.Errorf("rate: Wait(n=%d) exceeds limiter's burst %d", n, lim.burst)
|
||||
}
|
||||
// Check if ctx is already cancelled
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return ctx.Err()
|
||||
default:
|
||||
}
|
||||
// Determine wait limit
|
||||
now := time.Now()
|
||||
waitLimit := InfDuration
|
||||
if deadline, ok := ctx.Deadline(); ok {
|
||||
waitLimit = deadline.Sub(now)
|
||||
}
|
||||
// Reserve
|
||||
r := lim.reserveN(now, n, waitLimit)
|
||||
if !r.ok {
|
||||
return fmt.Errorf("rate: Wait(n=%d) would exceed context deadline", n)
|
||||
}
|
||||
// Wait
|
||||
t := time.NewTimer(r.DelayFrom(now))
|
||||
defer t.Stop()
|
||||
select {
|
||||
case <-t.C:
|
||||
// We can proceed.
|
||||
return nil
|
||||
case <-ctx.Done():
|
||||
// Context was canceled before we could proceed. Cancel the
|
||||
// reservation, which may permit other events to proceed sooner.
|
||||
r.Cancel()
|
||||
return ctx.Err()
|
||||
}
|
||||
}
|
||||
|
||||
// SetLimit is shorthand for SetLimitAt(time.Now(), newLimit).
|
||||
func (lim *Limiter) SetLimit(newLimit Limit) {
|
||||
lim.SetLimitAt(time.Now(), newLimit)
|
||||
}
|
||||
|
||||
// SetLimitAt sets a new Limit for the limiter. The new Limit, and Burst, may be violated
|
||||
// or underutilized by those which reserved (using Reserve or Wait) but did not yet act
|
||||
// before SetLimitAt was called.
|
||||
func (lim *Limiter) SetLimitAt(now time.Time, newLimit Limit) {
|
||||
lim.mu.Lock()
|
||||
defer lim.mu.Unlock()
|
||||
|
||||
now, _, tokens := lim.advance(now)
|
||||
|
||||
lim.last = now
|
||||
lim.tokens = tokens
|
||||
lim.limit = newLimit
|
||||
}
|
||||
|
||||
// reserveN is a helper method for AllowN, ReserveN, and WaitN.
|
||||
// maxFutureReserve specifies the maximum reservation wait duration allowed.
|
||||
// reserveN returns Reservation, not *Reservation, to avoid allocation in AllowN and WaitN.
|
||||
func (lim *Limiter) reserveN(now time.Time, n int, maxFutureReserve time.Duration) Reservation {
|
||||
lim.mu.Lock()
|
||||
|
||||
if lim.limit == Inf {
|
||||
lim.mu.Unlock()
|
||||
return Reservation{
|
||||
ok: true,
|
||||
lim: lim,
|
||||
tokens: n,
|
||||
timeToAct: now,
|
||||
}
|
||||
}
|
||||
|
||||
now, last, tokens := lim.advance(now)
|
||||
|
||||
// Calculate the remaining number of tokens resulting from the request.
|
||||
tokens -= float64(n)
|
||||
|
||||
// Calculate the wait duration
|
||||
var waitDuration time.Duration
|
||||
if tokens < 0 {
|
||||
waitDuration = lim.limit.durationFromTokens(-tokens)
|
||||
}
|
||||
|
||||
// Decide result
|
||||
ok := n <= lim.burst && waitDuration <= maxFutureReserve
|
||||
|
||||
// Prepare reservation
|
||||
r := Reservation{
|
||||
ok: ok,
|
||||
lim: lim,
|
||||
limit: lim.limit,
|
||||
}
|
||||
if ok {
|
||||
r.tokens = n
|
||||
r.timeToAct = now.Add(waitDuration)
|
||||
}
|
||||
|
||||
// Update state
|
||||
if ok {
|
||||
lim.last = now
|
||||
lim.tokens = tokens
|
||||
lim.lastEvent = r.timeToAct
|
||||
} else {
|
||||
lim.last = last
|
||||
}
|
||||
|
||||
lim.mu.Unlock()
|
||||
return r
|
||||
}
|
||||
|
||||
// advance calculates and returns an updated state for lim resulting from the passage of time.
|
||||
// lim is not changed.
|
||||
func (lim *Limiter) advance(now time.Time) (newNow time.Time, newLast time.Time, newTokens float64) {
|
||||
last := lim.last
|
||||
if now.Before(last) {
|
||||
last = now
|
||||
}
|
||||
|
||||
// Avoid making delta overflow below when last is very old.
|
||||
maxElapsed := lim.limit.durationFromTokens(float64(lim.burst) - lim.tokens)
|
||||
elapsed := now.Sub(last)
|
||||
if elapsed > maxElapsed {
|
||||
elapsed = maxElapsed
|
||||
}
|
||||
|
||||
// Calculate the new number of tokens, due to time that passed.
|
||||
delta := lim.limit.tokensFromDuration(elapsed)
|
||||
tokens := lim.tokens + delta
|
||||
if burst := float64(lim.burst); tokens > burst {
|
||||
tokens = burst
|
||||
}
|
||||
|
||||
return now, last, tokens
|
||||
}
|
||||
|
||||
// durationFromTokens is a unit conversion function from the number of tokens to the duration
|
||||
// of time it takes to accumulate them at a rate of limit tokens per second.
|
||||
func (limit Limit) durationFromTokens(tokens float64) time.Duration {
|
||||
seconds := tokens / float64(limit)
|
||||
return time.Nanosecond * time.Duration(1e9*seconds)
|
||||
}
|
||||
|
||||
// tokensFromDuration is a unit conversion function from a time duration to the number of tokens
|
||||
// which could be accumulated during that duration at a rate of limit tokens per second.
|
||||
func (limit Limit) tokensFromDuration(d time.Duration) float64 {
|
||||
return d.Seconds() * float64(limit)
|
||||
}
|
|
@ -0,0 +1,21 @@
|
|||
// Copyright 2017 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// +build !go1.7
|
||||
|
||||
package rate
|
||||
|
||||
import "golang.org/x/net/context"
|
||||
|
||||
// Wait is shorthand for WaitN(ctx, 1).
|
||||
func (lim *Limiter) Wait(ctx context.Context) (err error) {
|
||||
return lim.waitN(ctx, 1)
|
||||
}
|
||||
|
||||
// WaitN blocks until lim permits n events to happen.
|
||||
// It returns an error if n exceeds the Limiter's burst size, the Context is
|
||||
// canceled, or the expected wait time exceeds the Context's Deadline.
|
||||
func (lim *Limiter) WaitN(ctx context.Context, n int) (err error) {
|
||||
return lim.waitN(ctx, n)
|
||||
}
|
|
@ -0,0 +1,21 @@
|
|||
// Copyright 2017 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// +build go1.7
|
||||
|
||||
package rate
|
||||
|
||||
import "context"
|
||||
|
||||
// Wait is shorthand for WaitN(ctx, 1).
|
||||
func (lim *Limiter) Wait(ctx context.Context) (err error) {
|
||||
return lim.waitN(ctx, 1)
|
||||
}
|
||||
|
||||
// WaitN blocks until lim permits n events to happen.
|
||||
// It returns an error if n exceeds the Limiter's burst size, the Context is
|
||||
// canceled, or the expected wait time exceeds the Context's Deadline.
|
||||
func (lim *Limiter) WaitN(ctx context.Context, n int) (err error) {
|
||||
return lim.waitN(ctx, n)
|
||||
}
|
Loading…
Reference in New Issue