diff options
Diffstat (limited to 'vendor/github.com/juju/ratelimit')
| -rw-r--r-- | vendor/github.com/juju/ratelimit/LICENSE | 191 | ||||
| -rw-r--r-- | vendor/github.com/juju/ratelimit/README.md | 117 | ||||
| -rw-r--r-- | vendor/github.com/juju/ratelimit/ratelimit.go | 284 | ||||
| -rw-r--r-- | vendor/github.com/juju/ratelimit/reader.go | 51 |
4 files changed, 0 insertions, 643 deletions
diff --git a/vendor/github.com/juju/ratelimit/LICENSE b/vendor/github.com/juju/ratelimit/LICENSE deleted file mode 100644 index ade9307b3..000000000 --- a/vendor/github.com/juju/ratelimit/LICENSE +++ /dev/null @@ -1,191 +0,0 @@ -All files in this repository are licensed as follows. If you contribute -to this repository, it is assumed that you license your contribution -under the same license unless you state otherwise. - -All files Copyright (C) 2015 Canonical Ltd. unless otherwise specified in the file. - -This software is licensed under the LGPLv3, included below. - -As a special exception to the GNU Lesser General Public License version 3 -("LGPL3"), the copyright holders of this Library give you permission to -convey to a third party a Combined Work that links statically or dynamically -to this Library without providing any Minimal Corresponding Source or -Minimal Application Code as set out in 4d or providing the installation -information set out in section 4e, provided that you comply with the other -provisions of LGPL3 and provided that you meet, for the Application the -terms and conditions of the license(s) which apply to the Application. - -Except as stated in this special exception, the provisions of LGPL3 will -continue to comply in full to this Library. If you modify this Library, you -may apply this exception to your version of this Library, but you are not -obliged to do so. If you do not wish to do so, delete this exception -statement from your version. This exception does not (and cannot) modify any -license terms which apply to the Application, with which you must still -comply. - - - GNU LESSER GENERAL PUBLIC LICENSE - Version 3, 29 June 2007 - - Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/> - Everyone is permitted to copy and distribute verbatim copies - of this license document, but changing it is not allowed. - - - This version of the GNU Lesser General Public License incorporates -the terms and conditions of version 3 of the GNU General Public -License, supplemented by the additional permissions listed below. - - 0. Additional Definitions. - - As used herein, "this License" refers to version 3 of the GNU Lesser -General Public License, and the "GNU GPL" refers to version 3 of the GNU -General Public License. - - "The Library" refers to a covered work governed by this License, -other than an Application or a Combined Work as defined below. - - An "Application" is any work that makes use of an interface provided -by the Library, but which is not otherwise based on the Library. -Defining a subclass of a class defined by the Library is deemed a mode -of using an interface provided by the Library. - - A "Combined Work" is a work produced by combining or linking an -Application with the Library. The particular version of the Library -with which the Combined Work was made is also called the "Linked -Version". - - The "Minimal Corresponding Source" for a Combined Work means the -Corresponding Source for the Combined Work, excluding any source code -for portions of the Combined Work that, considered in isolation, are -based on the Application, and not on the Linked Version. - - The "Corresponding Application Code" for a Combined Work means the -object code and/or source code for the Application, including any data -and utility programs needed for reproducing the Combined Work from the -Application, but excluding the System Libraries of the Combined Work. - - 1. Exception to Section 3 of the GNU GPL. - - You may convey a covered work under sections 3 and 4 of this License -without being bound by section 3 of the GNU GPL. - - 2. Conveying Modified Versions. - - If you modify a copy of the Library, and, in your modifications, a -facility refers to a function or data to be supplied by an Application -that uses the facility (other than as an argument passed when the -facility is invoked), then you may convey a copy of the modified -version: - - a) under this License, provided that you make a good faith effort to - ensure that, in the event an Application does not supply the - function or data, the facility still operates, and performs - whatever part of its purpose remains meaningful, or - - b) under the GNU GPL, with none of the additional permissions of - this License applicable to that copy. - - 3. Object Code Incorporating Material from Library Header Files. - - The object code form of an Application may incorporate material from -a header file that is part of the Library. You may convey such object -code under terms of your choice, provided that, if the incorporated -material is not limited to numerical parameters, data structure -layouts and accessors, or small macros, inline functions and templates -(ten or fewer lines in length), you do both of the following: - - a) Give prominent notice with each copy of the object code that the - Library is used in it and that the Library and its use are - covered by this License. - - b) Accompany the object code with a copy of the GNU GPL and this license - document. - - 4. Combined Works. - - You may convey a Combined Work under terms of your choice that, -taken together, effectively do not restrict modification of the -portions of the Library contained in the Combined Work and reverse -engineering for debugging such modifications, if you also do each of -the following: - - a) Give prominent notice with each copy of the Combined Work that - the Library is used in it and that the Library and its use are - covered by this License. - - b) Accompany the Combined Work with a copy of the GNU GPL and this license - document. - - c) For a Combined Work that displays copyright notices during - execution, include the copyright notice for the Library among - these notices, as well as a reference directing the user to the - copies of the GNU GPL and this license document. - - d) Do one of the following: - - 0) Convey the Minimal Corresponding Source under the terms of this - License, and the Corresponding Application Code in a form - suitable for, and under terms that permit, the user to - recombine or relink the Application with a modified version of - the Linked Version to produce a modified Combined Work, in the - manner specified by section 6 of the GNU GPL for conveying - Corresponding Source. - - 1) Use a suitable shared library mechanism for linking with the - Library. A suitable mechanism is one that (a) uses at run time - a copy of the Library already present on the user's computer - system, and (b) will operate properly with a modified version - of the Library that is interface-compatible with the Linked - Version. - - e) Provide Installation Information, but only if you would otherwise - be required to provide such information under section 6 of the - GNU GPL, and only to the extent that such information is - necessary to install and execute a modified version of the - Combined Work produced by recombining or relinking the - Application with a modified version of the Linked Version. (If - you use option 4d0, the Installation Information must accompany - the Minimal Corresponding Source and Corresponding Application - Code. If you use option 4d1, you must provide the Installation - Information in the manner specified by section 6 of the GNU GPL - for conveying Corresponding Source.) - - 5. Combined Libraries. - - You may place library facilities that are a work based on the -Library side by side in a single library together with other library -facilities that are not Applications and are not covered by this -License, and convey such a combined library under terms of your -choice, if you do both of the following: - - a) Accompany the combined library with a copy of the same work based - on the Library, uncombined with any other library facilities, - conveyed under the terms of this License. - - b) Give prominent notice with the combined library that part of it - is a work based on the Library, and explaining where to find the - accompanying uncombined form of the same work. - - 6. Revised Versions of the GNU Lesser General Public License. - - The Free Software Foundation may publish revised and/or new versions -of the GNU Lesser General Public License from time to time. Such new -versions will be similar in spirit to the present version, but may -differ in detail to address new problems or concerns. - - Each version is given a distinguishing version number. If the -Library as you received it specifies that a certain numbered version -of the GNU Lesser General Public License "or any later version" -applies to it, you have the option of following the terms and -conditions either of that published version or of any later version -published by the Free Software Foundation. If the Library as you -received it does not specify a version number of the GNU Lesser -General Public License, you may choose any version of the GNU Lesser -General Public License ever published by the Free Software Foundation. - - If the Library as you received it specifies that a proxy can decide -whether future versions of the GNU Lesser General Public License shall -apply, that proxy's public statement of acceptance of any version is -permanent authorization for you to choose that version for the -Library. diff --git a/vendor/github.com/juju/ratelimit/README.md b/vendor/github.com/juju/ratelimit/README.md deleted file mode 100644 index a0fdfe2b1..000000000 --- a/vendor/github.com/juju/ratelimit/README.md +++ /dev/null @@ -1,117 +0,0 @@ -# ratelimit --- - import "github.com/juju/ratelimit" - -The ratelimit package provides an efficient token bucket implementation. See -http://en.wikipedia.org/wiki/Token_bucket. - -## Usage - -#### func Reader - -```go -func Reader(r io.Reader, bucket *Bucket) io.Reader -``` -Reader returns a reader that is rate limited by the given token bucket. Each -token in the bucket represents one byte. - -#### func Writer - -```go -func Writer(w io.Writer, bucket *Bucket) io.Writer -``` -Writer returns a writer that is rate limited by the given token bucket. Each -token in the bucket represents one byte. - -#### type Bucket - -```go -type Bucket struct { -} -``` - -Bucket represents a token bucket that fills at a predetermined rate. Methods on -Bucket may be called concurrently. - -#### func NewBucket - -```go -func NewBucket(fillInterval time.Duration, capacity int64) *Bucket -``` -NewBucket returns a new token bucket that fills at the rate of one token every -fillInterval, up to the given maximum capacity. Both arguments must be positive. -The bucket is initially full. - -#### func NewBucketWithQuantum - -```go -func NewBucketWithQuantum(fillInterval time.Duration, capacity, quantum int64) *Bucket -``` -NewBucketWithQuantum is similar to NewBucket, but allows the specification of -the quantum size - quantum tokens are added every fillInterval. - -#### func NewBucketWithRate - -```go -func NewBucketWithRate(rate float64, capacity int64) *Bucket -``` -NewBucketWithRate returns a token bucket that fills the bucket at the rate of -rate tokens per second up to the given maximum capacity. Because of limited -clock resolution, at high rates, the actual rate may be up to 1% different from -the specified rate. - -#### func (*Bucket) Rate - -```go -func (tb *Bucket) Rate() float64 -``` -Rate returns the fill rate of the bucket, in tokens per second. - -#### func (*Bucket) Take - -```go -func (tb *Bucket) Take(count int64) time.Duration -``` -Take takes count tokens from the bucket without blocking. It returns the time -that the caller should wait until the tokens are actually available. - -Note that if the request is irrevocable - there is no way to return tokens to -the bucket once this method commits us to taking them. - -#### func (*Bucket) TakeAvailable - -```go -func (tb *Bucket) TakeAvailable(count int64) int64 -``` -TakeAvailable takes up to count immediately available tokens from the bucket. It -returns the number of tokens removed, or zero if there are no available tokens. -It does not block. - -#### func (*Bucket) TakeMaxDuration - -```go -func (tb *Bucket) TakeMaxDuration(count int64, maxWait time.Duration) (time.Duration, bool) -``` -TakeMaxDuration is like Take, except that it will only take tokens from the -bucket if the wait time for the tokens is no greater than maxWait. - -If it would take longer than maxWait for the tokens to become available, it does -nothing and reports false, otherwise it returns the time that the caller should -wait until the tokens are actually available, and reports true. - -#### func (*Bucket) Wait - -```go -func (tb *Bucket) Wait(count int64) -``` -Wait takes count tokens from the bucket, waiting until they are available. - -#### func (*Bucket) WaitMaxDuration - -```go -func (tb *Bucket) WaitMaxDuration(count int64, maxWait time.Duration) bool -``` -WaitMaxDuration is like Wait except that it will only take tokens from the -bucket if it needs to wait for no greater than maxWait. It reports whether any -tokens have been removed from the bucket If no tokens have been removed, it -returns immediately. diff --git a/vendor/github.com/juju/ratelimit/ratelimit.go b/vendor/github.com/juju/ratelimit/ratelimit.go deleted file mode 100644 index 1c3f25b2e..000000000 --- a/vendor/github.com/juju/ratelimit/ratelimit.go +++ /dev/null @@ -1,284 +0,0 @@ -// Copyright 2014 Canonical Ltd. -// Licensed under the LGPLv3 with static-linking exception. -// See LICENCE file for details. - -// Package ratelimit provides an efficient token bucket implementation -// that can be used to limit the rate of arbitrary things. -// See http://en.wikipedia.org/wiki/Token_bucket. -package ratelimit - -import ( - "math" - "strconv" - "sync" - "time" -) - -// Bucket represents a token bucket that fills at a predetermined rate. -// Methods on Bucket may be called concurrently. -type Bucket struct { - startTime time.Time - capacity int64 - quantum int64 - fillInterval time.Duration - clock Clock - - // The mutex guards the fields following it. - mu sync.Mutex - - // avail holds the number of available tokens - // in the bucket, as of availTick ticks from startTime. - // It will be negative when there are consumers - // waiting for tokens. - avail int64 - availTick int64 -} - -// Clock is used to inject testable fakes. -type Clock interface { - Now() time.Time - Sleep(d time.Duration) -} - -// realClock implements Clock in terms of standard time functions. -type realClock struct{} - -// Now is identical to time.Now. -func (realClock) Now() time.Time { - return time.Now() -} - -// Sleep is identical to time.Sleep. -func (realClock) Sleep(d time.Duration) { - time.Sleep(d) -} - -// NewBucket returns a new token bucket that fills at the -// rate of one token every fillInterval, up to the given -// maximum capacity. Both arguments must be -// positive. The bucket is initially full. -func NewBucket(fillInterval time.Duration, capacity int64) *Bucket { - return NewBucketWithClock(fillInterval, capacity, realClock{}) -} - -// NewBucketWithClock is identical to NewBucket but injects a testable clock -// interface. -func NewBucketWithClock(fillInterval time.Duration, capacity int64, clock Clock) *Bucket { - return NewBucketWithQuantumAndClock(fillInterval, capacity, 1, clock) -} - -// rateMargin specifes the allowed variance of actual -// rate from specified rate. 1% seems reasonable. -const rateMargin = 0.01 - -// NewBucketWithRate returns a token bucket that fills the bucket -// at the rate of rate tokens per second up to the given -// maximum capacity. Because of limited clock resolution, -// at high rates, the actual rate may be up to 1% different from the -// specified rate. -func NewBucketWithRate(rate float64, capacity int64) *Bucket { - return NewBucketWithRateAndClock(rate, capacity, realClock{}) -} - -// NewBucketWithRateAndClock is identical to NewBucketWithRate but injects a -// testable clock interface. -func NewBucketWithRateAndClock(rate float64, capacity int64, clock Clock) *Bucket { - for quantum := int64(1); quantum < 1<<50; quantum = nextQuantum(quantum) { - fillInterval := time.Duration(1e9 * float64(quantum) / rate) - if fillInterval <= 0 { - continue - } - tb := NewBucketWithQuantumAndClock(fillInterval, capacity, quantum, clock) - if diff := math.Abs(tb.Rate() - rate); diff/rate <= rateMargin { - return tb - } - } - panic("cannot find suitable quantum for " + strconv.FormatFloat(rate, 'g', -1, 64)) -} - -// nextQuantum returns the next quantum to try after q. -// We grow the quantum exponentially, but slowly, so we -// get a good fit in the lower numbers. -func nextQuantum(q int64) int64 { - q1 := q * 11 / 10 - if q1 == q { - q1++ - } - return q1 -} - -// NewBucketWithQuantum is similar to NewBucket, but allows -// the specification of the quantum size - quantum tokens -// are added every fillInterval. -func NewBucketWithQuantum(fillInterval time.Duration, capacity, quantum int64) *Bucket { - return NewBucketWithQuantumAndClock(fillInterval, capacity, quantum, realClock{}) -} - -// NewBucketWithQuantumAndClock is identical to NewBucketWithQuantum but injects -// a testable clock interface. -func NewBucketWithQuantumAndClock(fillInterval time.Duration, capacity, quantum int64, clock Clock) *Bucket { - if fillInterval <= 0 { - panic("token bucket fill interval is not > 0") - } - if capacity <= 0 { - panic("token bucket capacity is not > 0") - } - if quantum <= 0 { - panic("token bucket quantum is not > 0") - } - return &Bucket{ - clock: clock, - startTime: clock.Now(), - capacity: capacity, - quantum: quantum, - avail: capacity, - fillInterval: fillInterval, - } -} - -// Wait takes count tokens from the bucket, waiting until they are -// available. -func (tb *Bucket) Wait(count int64) { - if d := tb.Take(count); d > 0 { - tb.clock.Sleep(d) - } -} - -// WaitMaxDuration is like Wait except that it will -// only take tokens from the bucket if it needs to wait -// for no greater than maxWait. It reports whether -// any tokens have been removed from the bucket -// If no tokens have been removed, it returns immediately. -func (tb *Bucket) WaitMaxDuration(count int64, maxWait time.Duration) bool { - d, ok := tb.TakeMaxDuration(count, maxWait) - if d > 0 { - tb.clock.Sleep(d) - } - return ok -} - -const infinityDuration time.Duration = 0x7fffffffffffffff - -// Take takes count tokens from the bucket without blocking. It returns -// the time that the caller should wait until the tokens are actually -// available. -// -// Note that if the request is irrevocable - there is no way to return -// tokens to the bucket once this method commits us to taking them. -func (tb *Bucket) Take(count int64) time.Duration { - d, _ := tb.take(tb.clock.Now(), count, infinityDuration) - return d -} - -// TakeMaxDuration is like Take, except that -// it will only take tokens from the bucket if the wait -// time for the tokens is no greater than maxWait. -// -// If it would take longer than maxWait for the tokens -// to become available, it does nothing and reports false, -// otherwise it returns the time that the caller should -// wait until the tokens are actually available, and reports -// true. -func (tb *Bucket) TakeMaxDuration(count int64, maxWait time.Duration) (time.Duration, bool) { - return tb.take(tb.clock.Now(), count, maxWait) -} - -// TakeAvailable takes up to count immediately available tokens from the -// bucket. It returns the number of tokens removed, or zero if there are -// no available tokens. It does not block. -func (tb *Bucket) TakeAvailable(count int64) int64 { - return tb.takeAvailable(tb.clock.Now(), count) -} - -// takeAvailable is the internal version of TakeAvailable - it takes the -// current time as an argument to enable easy testing. -func (tb *Bucket) takeAvailable(now time.Time, count int64) int64 { - if count <= 0 { - return 0 - } - tb.mu.Lock() - defer tb.mu.Unlock() - - tb.adjust(now) - if tb.avail <= 0 { - return 0 - } - if count > tb.avail { - count = tb.avail - } - tb.avail -= count - return count -} - -// Available returns the number of available tokens. It will be negative -// when there are consumers waiting for tokens. Note that if this -// returns greater than zero, it does not guarantee that calls that take -// tokens from the buffer will succeed, as the number of available -// tokens could have changed in the meantime. This method is intended -// primarily for metrics reporting and debugging. -func (tb *Bucket) Available() int64 { - return tb.available(tb.clock.Now()) -} - -// available is the internal version of available - it takes the current time as -// an argument to enable easy testing. -func (tb *Bucket) available(now time.Time) int64 { - tb.mu.Lock() - defer tb.mu.Unlock() - tb.adjust(now) - return tb.avail -} - -// Capacity returns the capacity that the bucket was created with. -func (tb *Bucket) Capacity() int64 { - return tb.capacity -} - -// Rate returns the fill rate of the bucket, in tokens per second. -func (tb *Bucket) Rate() float64 { - return 1e9 * float64(tb.quantum) / float64(tb.fillInterval) -} - -// take is the internal version of Take - it takes the current time as -// an argument to enable easy testing. -func (tb *Bucket) take(now time.Time, count int64, maxWait time.Duration) (time.Duration, bool) { - if count <= 0 { - return 0, true - } - tb.mu.Lock() - defer tb.mu.Unlock() - - currentTick := tb.adjust(now) - avail := tb.avail - count - if avail >= 0 { - tb.avail = avail - return 0, true - } - // Round up the missing tokens to the nearest multiple - // of quantum - the tokens won't be available until - // that tick. - endTick := currentTick + (-avail+tb.quantum-1)/tb.quantum - endTime := tb.startTime.Add(time.Duration(endTick) * tb.fillInterval) - waitTime := endTime.Sub(now) - if waitTime > maxWait { - return 0, false - } - tb.avail = avail - return waitTime, true -} - -// adjust adjusts the current bucket capacity based on the current time. -// It returns the current tick. -func (tb *Bucket) adjust(now time.Time) (currentTick int64) { - currentTick = int64(now.Sub(tb.startTime) / tb.fillInterval) - - if tb.avail >= tb.capacity { - return - } - tb.avail += (currentTick - tb.availTick) * tb.quantum - if tb.avail > tb.capacity { - tb.avail = tb.capacity - } - tb.availTick = currentTick - return -} diff --git a/vendor/github.com/juju/ratelimit/reader.go b/vendor/github.com/juju/ratelimit/reader.go deleted file mode 100644 index 6403bf78d..000000000 --- a/vendor/github.com/juju/ratelimit/reader.go +++ /dev/null @@ -1,51 +0,0 @@ -// Copyright 2014 Canonical Ltd. -// Licensed under the LGPLv3 with static-linking exception. -// See LICENCE file for details. - -package ratelimit - -import "io" - -type reader struct { - r io.Reader - bucket *Bucket -} - -// Reader returns a reader that is rate limited by -// the given token bucket. Each token in the bucket -// represents one byte. -func Reader(r io.Reader, bucket *Bucket) io.Reader { - return &reader{ - r: r, - bucket: bucket, - } -} - -func (r *reader) Read(buf []byte) (int, error) { - n, err := r.r.Read(buf) - if n <= 0 { - return n, err - } - r.bucket.Wait(int64(n)) - return n, err -} - -type writer struct { - w io.Writer - bucket *Bucket -} - -// Writer returns a reader that is rate limited by -// the given token bucket. Each token in the bucket -// represents one byte. -func Writer(w io.Writer, bucket *Bucket) io.Writer { - return &writer{ - w: w, - bucket: bucket, - } -} - -func (w *writer) Write(buf []byte) (int, error) { - w.bucket.Wait(int64(len(buf))) - return w.w.Write(buf) -} |