From 5ac7466be5deaf6e0391f2d214bb1794a170e78e Mon Sep 17 00:00:00 2001 From: Gyu-Ho Lee Date: Tue, 20 Dec 2016 12:46:39 -0800 Subject: [PATCH] vendor: add 'time/rate' --- glide.lock | 12 +- glide.yaml | 4 + .../prometheus/common/model/metric.go | 2 +- vendor/golang.org/x/image/font/font.go | 87 +++++ vendor/golang.org/x/time/LICENSE | 27 ++ vendor/golang.org/x/time/PATENTS | 22 ++ vendor/golang.org/x/time/rate/rate.go | 368 ++++++++++++++++++ 7 files changed, 517 insertions(+), 5 deletions(-) create mode 100644 vendor/golang.org/x/time/LICENSE create mode 100644 vendor/golang.org/x/time/PATENTS create mode 100644 vendor/golang.org/x/time/rate/rate.go diff --git a/glide.lock b/glide.lock index 107d4b47..726c1f5a 100644 --- a/glide.lock +++ b/glide.lock @@ -1,5 +1,5 @@ -hash: 7e56e2b0795ce80b8d55b4ed02cea643952ce670b7f5d6cd09fbc5817b88db86 -updated: 2016-12-19T11:51:16.093755958-08:00 +hash: d4a1ceef843a6f16e969081a50aeb9117cdca088ddee1f652b847f1bf322a03d +updated: 2016-12-20T12:42:08.836209288-08:00 imports: - name: bitbucket.org/zombiezen/gopdf version: 1c63dc69751bc45441c2ce1f56b631c55294b4d5 @@ -133,7 +133,7 @@ imports: subpackages: - go - name: github.com/prometheus/common - version: 195bde7883f7c39ea62b0d92ab7359b5327065cb + version: 6d76b79f239843a04e8ad8dfd8fcadfa3920236f subpackages: - expfmt - internal/bitbucket.org/ww/goautoneg @@ -153,7 +153,7 @@ imports: subpackages: - codec - name: golang.org/x/image - version: ed90ab82a880d9b63d5adecdc23c5cd5020addc1 + version: f1b1ff53e10e288d0ab6f161067c0a69b72cee28 subpackages: - draw - font @@ -178,6 +178,10 @@ imports: - internal - jws - jwt +- name: golang.org/x/time + version: a4bde12657593d5e90d0533a3e4fd95e635124cb + subpackages: + - rate - name: google.golang.org/api version: a53f28dc539c26b08a77fc5ae954e02917686ef4 subpackages: diff --git a/glide.yaml b/glide.yaml index 080863dc..59be3064 100644 --- a/glide.yaml +++ b/glide.yaml @@ -103,3 +103,7 @@ import: version: 53feefa2559fb8dfa8d81baad31be332c97d6c77 - package: github.com/spf13/pflag version: 5ccb023bc27df288a957c5e994cd44fd19619465 +- package: golang.org/x/time + version: a4bde12657593d5e90d0533a3e4fd95e635124cb + subpackages: + - rate diff --git a/vendor/github.com/prometheus/common/model/metric.go b/vendor/github.com/prometheus/common/model/metric.go index 9dff899c..f7250909 100644 --- a/vendor/github.com/prometheus/common/model/metric.go +++ b/vendor/github.com/prometheus/common/model/metric.go @@ -44,7 +44,7 @@ func (m Metric) Before(o Metric) bool { // Clone returns a copy of the Metric. func (m Metric) Clone() Metric { - clone := Metric{} + clone := make(Metric, len(m)) for k, v := range m { clone[k] = v } diff --git a/vendor/golang.org/x/image/font/font.go b/vendor/golang.org/x/image/font/font.go index 36a16380..d523baf4 100644 --- a/vendor/golang.org/x/image/font/font.go +++ b/vendor/golang.org/x/image/font/font.go @@ -169,6 +169,26 @@ func (d *Drawer) DrawString(s string) { } } +// BoundBytes returns the bounding box of s, drawn at the drawer dot, as well as +// the advance. +// +// It is equivalent to BoundBytes(string(s)) but may be more efficient. +func (d *Drawer) BoundBytes(s []byte) (bounds fixed.Rectangle26_6, advance fixed.Int26_6) { + bounds, advance = BoundBytes(d.Face, s) + bounds.Min = bounds.Min.Add(d.Dot) + bounds.Max = bounds.Max.Add(d.Dot) + return +} + +// BoundString returns the bounding box of s, drawn at the drawer dot, as well +// as the advance. +func (d *Drawer) BoundString(s string) (bounds fixed.Rectangle26_6, advance fixed.Int26_6) { + bounds, advance = BoundString(d.Face, s) + bounds.Min = bounds.Min.Add(d.Dot) + bounds.Max = bounds.Max.Add(d.Dot) + return +} + // MeasureBytes returns how far dot would advance by drawing s. // // It is equivalent to MeasureString(string(s)) but may be more efficient. @@ -181,6 +201,73 @@ func (d *Drawer) MeasureString(s string) (advance fixed.Int26_6) { return MeasureString(d.Face, s) } +// BoundBytes returns the bounding box of s with f, drawn at a dot equal to the +// origin, as well as the advance. +// +// It is equivalent to BoundString(string(s)) but may be more efficient. +func BoundBytes(f Face, s []byte) (bounds fixed.Rectangle26_6, advance fixed.Int26_6) { + prevC := rune(-1) + for len(s) > 0 { + c, size := utf8.DecodeRune(s) + s = s[size:] + if prevC >= 0 { + advance += f.Kern(prevC, c) + } + b, a, ok := f.GlyphBounds(c) + if !ok { + // TODO: is falling back on the U+FFFD glyph the responsibility of + // the Drawer or the Face? + // TODO: set prevC = '\ufffd'? + continue + } + bounds = grow(bounds, b, advance) + advance += a + prevC = c + } + return +} + +// BoundString returns the bounding box of s with f, drawn at a dot equal to the +// origin, as well as the advance. +func BoundString(f Face, s string) (bounds fixed.Rectangle26_6, advance fixed.Int26_6) { + prevC := rune(-1) + for _, c := range s { + if prevC >= 0 { + advance += f.Kern(prevC, c) + } + b, a, ok := f.GlyphBounds(c) + if !ok { + // TODO: is falling back on the U+FFFD glyph the responsibility of + // the Drawer or the Face? + // TODO: set prevC = '\ufffd'? + continue + } + bounds = grow(bounds, b, advance) + advance += a + prevC = c + } + return +} + +// grow returns the smallest rectangle containing both b and b2+shift. +func grow(b, b2 fixed.Rectangle26_6, shift fixed.Int26_6) fixed.Rectangle26_6 { + x := b2.Min.X + shift + if b.Min.X > x { + b.Min.X = x + } + if b.Min.Y > b2.Min.Y { + b.Min.Y = b2.Min.Y + } + x = b2.Max.X + shift + if b.Max.X < x { + b.Max.X = x + } + if b.Max.Y < b2.Max.Y { + b.Max.Y = b2.Max.Y + } + return b +} + // MeasureBytes returns how far dot would advance by drawing s with f. // // It is equivalent to MeasureString(string(s)) but may be more efficient. diff --git a/vendor/golang.org/x/time/LICENSE b/vendor/golang.org/x/time/LICENSE new file mode 100644 index 00000000..6a66aea5 --- /dev/null +++ b/vendor/golang.org/x/time/LICENSE @@ -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. diff --git a/vendor/golang.org/x/time/PATENTS b/vendor/golang.org/x/time/PATENTS new file mode 100644 index 00000000..73309904 --- /dev/null +++ b/vendor/golang.org/x/time/PATENTS @@ -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. diff --git a/vendor/golang.org/x/time/rate/rate.go b/vendor/golang.org/x/time/rate/rate.go new file mode 100644 index 00000000..2131b921 --- /dev/null +++ b/vendor/golang.org/x/time/rate/rate.go @@ -0,0 +1,368 @@ +// 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" + + "golang.org/x/net/context" +) + +// 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, ok := lim.ReserveN(time.Now(), 1) +// if !ok { +// // Not allowed to act! Did you remember to set lim.burst to be > 0 ? +// } +// 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 +} + +// 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) { + if n > lim.burst { + 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() + defer lim.mu.Unlock() + + if lim.limit == Inf { + 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 + } + + 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) +}