mirror of https://github.com/fatedier/frp
fatedier
5 years ago
committed by
GitHub
14 changed files with 719 additions and 13 deletions
@ -0,0 +1,100 @@
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// Copyright 2019 fatedier, fatedier@gmail.com
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package config |
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import ( |
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"errors" |
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"strconv" |
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"strings" |
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) |
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const ( |
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MB = 1024 * 1024 |
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KB = 1024 |
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) |
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type BandwithQuantity struct { |
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s string // MB or KB
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i int64 // bytes
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} |
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func NewBandwithQuantity(s string) (BandwithQuantity, error) { |
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q := BandwithQuantity{} |
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err := q.UnmarshalString(s) |
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if err != nil { |
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return q, err |
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} |
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return q, nil |
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} |
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func (q *BandwithQuantity) Equal(u *BandwithQuantity) bool { |
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if q == nil && u == nil { |
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return true |
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} |
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if q != nil && u != nil { |
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return q.i == u.i |
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} |
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return false |
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} |
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func (q *BandwithQuantity) String() string { |
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return q.s |
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} |
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func (q *BandwithQuantity) UnmarshalString(s string) error { |
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q.s = strings.TrimSpace(s) |
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if q.s == "" { |
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return nil |
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} |
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var ( |
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base int64 |
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f float64 |
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err error |
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) |
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if strings.HasSuffix(s, "MB") { |
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base = MB |
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s = strings.TrimSuffix(s, "MB") |
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f, err = strconv.ParseFloat(s, 64) |
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if err != nil { |
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return err |
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} |
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} else if strings.HasSuffix(s, "KB") { |
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base = KB |
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s = strings.TrimSuffix(s, "KB") |
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f, err = strconv.ParseFloat(s, 64) |
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if err != nil { |
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return err |
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} |
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} else { |
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return errors.New("unit not support") |
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} |
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q.i = int64(f * float64(base)) |
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return nil |
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} |
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func (q *BandwithQuantity) UnmarshalJSON(b []byte) error { |
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return q.UnmarshalString(string(b)) |
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} |
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func (q *BandwithQuantity) MarshalJSON() ([]byte, error) { |
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return []byte(q.s), nil |
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} |
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func (q *BandwithQuantity) Bytes() int64 { |
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return q.i |
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} |
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@ -0,0 +1,51 @@
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// Copyright 2019 fatedier, fatedier@gmail.com
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
|
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// You may obtain a copy of the License at
|
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
|
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// distributed under the License is distributed on an "AS IS" BASIS,
|
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
|
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// limitations under the License.
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package limit |
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import ( |
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"context" |
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"io" |
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"golang.org/x/time/rate" |
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) |
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type Reader struct { |
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r io.Reader |
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limiter *rate.Limiter |
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} |
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func NewReader(r io.Reader, limiter *rate.Limiter) *Reader { |
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return &Reader{ |
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r: r, |
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limiter: limiter, |
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} |
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} |
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func (r *Reader) Read(p []byte) (n int, err error) { |
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b := r.limiter.Burst() |
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if b < len(p) { |
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p = p[:b] |
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} |
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n, err = r.r.Read(p) |
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if err != nil { |
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return |
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} |
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err = r.limiter.WaitN(context.Background(), n) |
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if err != nil { |
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return |
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} |
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return |
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} |
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@ -0,0 +1,60 @@
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// Copyright 2019 fatedier, fatedier@gmail.com
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
|
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// you may not use this file except in compliance with the License.
|
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// You may obtain a copy of the License at
|
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
|
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// Unless required by applicable law or agreed to in writing, software
|
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// distributed under the License is distributed on an "AS IS" BASIS,
|
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
|
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// limitations under the License.
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package limit |
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import ( |
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"context" |
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"io" |
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"golang.org/x/time/rate" |
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) |
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type Writer struct { |
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w io.Writer |
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limiter *rate.Limiter |
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} |
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func NewWriter(w io.Writer, limiter *rate.Limiter) *Writer { |
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return &Writer{ |
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w: w, |
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limiter: limiter, |
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} |
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} |
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func (w *Writer) Write(p []byte) (n int, err error) { |
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var nn int |
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b := w.limiter.Burst() |
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for { |
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end := len(p) |
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if end == 0 { |
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break |
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} |
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if b < len(p) { |
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end = b |
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} |
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err = w.limiter.WaitN(context.Background(), end) |
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if err != nil { |
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return |
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} |
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nn, err = w.w.Write(p[:end]) |
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n += nn |
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if err != nil { |
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return |
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} |
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p = p[end:] |
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} |
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return |
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} |
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@ -0,0 +1,3 @@
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# This source code refers to The Go Authors for copyright purposes. |
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# The master list of authors is in the main Go distribution, |
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# visible at http://tip.golang.org/AUTHORS. |
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@ -0,0 +1,3 @@
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# This source code was written by the Go contributors. |
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# The master list of contributors is in the main Go distribution, |
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# visible at http://tip.golang.org/CONTRIBUTORS. |
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@ -0,0 +1,27 @@
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Copyright (c) 2009 The Go Authors. All rights reserved. |
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Redistribution and use in source and binary forms, with or without |
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modification, are permitted provided that the following conditions are |
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met: |
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|
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* 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. |
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* Neither the name of Google Inc. nor the names of its |
||||
contributors may be used to endorse or promote products derived from |
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this software without specific prior written permission. |
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|
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
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"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 |
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||||
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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@ -0,0 +1,22 @@
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Additional IP Rights Grant (Patents) |
||||
|
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"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 +1,400 @@
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// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package rate provides a rate limiter.
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package rate |
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import ( |
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"context" |
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"fmt" |
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"math" |
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"sync" |
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"time" |
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) |
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// Limit defines the maximum frequency of some events.
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// Limit is represented as number of events per second.
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// A zero Limit allows no events.
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type Limit float64 |
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// Inf is the infinite rate limit; it allows all events (even if burst is zero).
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const Inf = Limit(math.MaxFloat64) |
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// Every converts a minimum time interval between events to a Limit.
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func Every(interval time.Duration) Limit { |
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if interval <= 0 { |
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return Inf |
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} |
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return 1 / Limit(interval.Seconds()) |
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} |
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// A Limiter controls how frequently events are allowed to happen.
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// It implements a "token bucket" of size b, initially full and refilled
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// at rate r tokens per second.
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// Informally, in any large enough time interval, the Limiter limits the
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// rate to r tokens per second, with a maximum burst size of b events.
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// As a special case, if r == Inf (the infinite rate), b is ignored.
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// See https://en.wikipedia.org/wiki/Token_bucket for more about token buckets.
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//
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// The zero value is a valid Limiter, but it will reject all events.
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// Use NewLimiter to create non-zero Limiters.
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//
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// Limiter has three main methods, Allow, Reserve, and Wait.
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// Most callers should use Wait.
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//
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// Each of the three methods consumes a single token.
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// They differ in their behavior when no token is available.
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// If no token is available, Allow returns false.
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// If no token is available, Reserve returns a reservation for a future token
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// and the amount of time the caller must wait before using it.
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// If no token is available, Wait blocks until one can be obtained
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// or its associated context.Context is canceled.
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//
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// The methods AllowN, ReserveN, and WaitN consume n tokens.
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type Limiter struct { |
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limit Limit |
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burst int |
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mu sync.Mutex |
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tokens float64 |
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// last is the last time the limiter's tokens field was updated
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last time.Time |
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// lastEvent is the latest time of a rate-limited event (past or future)
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lastEvent time.Time |
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} |
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// Limit returns the maximum overall event rate.
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func (lim *Limiter) Limit() Limit { |
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lim.mu.Lock() |
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defer lim.mu.Unlock() |
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return lim.limit |
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} |
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// Burst returns the maximum burst size. Burst is the maximum number of tokens
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// that can be consumed in a single call to Allow, Reserve, or Wait, so higher
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// Burst values allow more events to happen at once.
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// A zero Burst allows no events, unless limit == Inf.
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func (lim *Limiter) Burst() int { |
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return lim.burst |
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} |
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// NewLimiter returns a new Limiter that allows events up to rate r and permits
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// bursts of at most b tokens.
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func NewLimiter(r Limit, b int) *Limiter { |
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return &Limiter{ |
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limit: r, |
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burst: b, |
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} |
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} |
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// Allow is shorthand for AllowN(time.Now(), 1).
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func (lim *Limiter) Allow() bool { |
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return lim.AllowN(time.Now(), 1) |
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} |
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// AllowN reports whether n events may happen at time now.
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// Use this method if you intend to drop / skip events that exceed the rate limit.
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// Otherwise use Reserve or Wait.
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func (lim *Limiter) AllowN(now time.Time, n int) bool { |
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return lim.reserveN(now, n, 0).ok |
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} |
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// A Reservation holds information about events that are permitted by a Limiter to happen after a delay.
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// A Reservation may be canceled, which may enable the Limiter to permit additional events.
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type Reservation struct { |
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ok bool |
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lim *Limiter |
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tokens int |
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timeToAct time.Time |
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// This is the Limit at reservation time, it can change later.
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limit Limit |
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} |
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// OK returns whether the limiter can provide the requested number of tokens
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// within the maximum wait time. If OK is false, Delay returns InfDuration, and
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// Cancel does nothing.
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func (r *Reservation) OK() bool { |
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return r.ok |
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} |
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// Delay is shorthand for DelayFrom(time.Now()).
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func (r *Reservation) Delay() time.Duration { |
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return r.DelayFrom(time.Now()) |
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} |
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// InfDuration is the duration returned by Delay when a Reservation is not OK.
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const InfDuration = time.Duration(1<<63 - 1) |
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// DelayFrom returns the duration for which the reservation holder must wait
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// before taking the reserved action. Zero duration means act immediately.
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// InfDuration means the limiter cannot grant the tokens requested in this
|
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// Reservation within the maximum wait time.
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func (r *Reservation) DelayFrom(now time.Time) time.Duration { |
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if !r.ok { |
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return InfDuration |
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} |
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delay := r.timeToAct.Sub(now) |
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if delay < 0 { |
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return 0 |
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} |
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return delay |
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} |
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|
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// Cancel is shorthand for CancelAt(time.Now()).
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func (r *Reservation) Cancel() { |
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r.CancelAt(time.Now()) |
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return |
||||
} |
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|
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// CancelAt indicates that the reservation holder will not perform the reserved action
|
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// and reverses the effects of this Reservation on the rate limit as much as possible,
|
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// considering that other reservations may have already been made.
|
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func (r *Reservation) CancelAt(now time.Time) { |
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if !r.ok { |
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return |
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} |
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|
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r.lim.mu.Lock() |
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defer r.lim.mu.Unlock() |
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|
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if r.lim.limit == Inf || r.tokens == 0 || r.timeToAct.Before(now) { |
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return |
||||
} |
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|
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// calculate tokens to restore
|
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// The duration between lim.lastEvent and r.timeToAct tells us how many tokens were reserved
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// after r was obtained. These tokens should not be restored.
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restoreTokens := float64(r.tokens) - r.limit.tokensFromDuration(r.lim.lastEvent.Sub(r.timeToAct)) |
||||
if restoreTokens <= 0 { |
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return |
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} |
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// advance time to now
|
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now, _, tokens := r.lim.advance(now) |
||||
// calculate new number of tokens
|
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tokens += restoreTokens |
||||
if burst := float64(r.lim.burst); tokens > burst { |
||||
tokens = burst |
||||
} |
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// update state
|
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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 |
||||
} |
||||
|
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// Reserve is shorthand for ReserveN(time.Now(), 1).
|
||||
func (lim *Limiter) Reserve() *Reservation { |
||||
return lim.ReserveN(time.Now(), 1) |
||||
} |
||||
|
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// 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 |
||||
} |
||||
|
||||
// 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.
|
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// The burst limit is ignored if the rate limit is Inf.
|
||||
func (lim *Limiter) WaitN(ctx context.Context, n int) (err error) { |
||||
lim.mu.Lock() |
||||
burst := lim.burst |
||||
limit := lim.limit |
||||
lim.mu.Unlock() |
||||
|
||||
if n > burst && limit != Inf { |
||||
return fmt.Errorf("rate: Wait(n=%d) exceeds limiter's burst %d", n, lim.burst) |
||||
} |
||||
// Check if ctx is already cancelled
|
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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 if necessary
|
||||
delay := r.DelayFrom(now) |
||||
if delay == 0 { |
||||
return nil |
||||
} |
||||
t := time.NewTimer(delay) |
||||
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 |
||||
} |
||||
|
||||
// SetBurst is shorthand for SetBurstAt(time.Now(), newBurst).
|
||||
func (lim *Limiter) SetBurst(newBurst int) { |
||||
lim.SetBurstAt(time.Now(), newBurst) |
||||
} |
||||
|
||||
// SetBurstAt sets a new burst size for the limiter.
|
||||
func (lim *Limiter) SetBurstAt(now time.Time, newBurst int) { |
||||
lim.mu.Lock() |
||||
defer lim.mu.Unlock() |
||||
|
||||
now, _, tokens := lim.advance(now) |
||||
|
||||
lim.last = now |
||||
lim.tokens = tokens |
||||
lim.burst = newBurst |
||||
} |
||||
|
||||
// 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 { |
||||
// Split the integer and fractional parts ourself to minimize rounding errors.
|
||||
// See golang.org/issues/34861.
|
||||
sec := float64(d/time.Second) * float64(limit) |
||||
nsec := float64(d%time.Second) * float64(limit) |
||||
return sec + nsec/1e9 |
||||
} |
||||
Loading…
Reference in new issue