152 lines
4.3 KiB
Go
152 lines
4.3 KiB
Go
/*
|
|
* Minio Go Library for Amazon S3 Compatible Cloud Storage (C) 2015, 2016 Minio, Inc.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
package minio
|
|
|
|
import (
|
|
"net"
|
|
"net/http"
|
|
"net/url"
|
|
"strings"
|
|
"time"
|
|
)
|
|
|
|
// MaxRetry is the maximum number of retries before stopping.
|
|
var MaxRetry = 5
|
|
|
|
// MaxJitter will randomize over the full exponential backoff time
|
|
const MaxJitter = 1.0
|
|
|
|
// NoJitter disables the use of jitter for randomizing the exponential backoff time
|
|
const NoJitter = 0.0
|
|
|
|
// DefaultRetryUnit - default unit multiplicative per retry.
|
|
// defaults to 1 second.
|
|
const DefaultRetryUnit = time.Second
|
|
|
|
// DefaultRetryCap - Each retry attempt never waits no longer than
|
|
// this maximum time duration.
|
|
const DefaultRetryCap = time.Second * 30
|
|
|
|
// newRetryTimer creates a timer with exponentially increasing
|
|
// delays until the maximum retry attempts are reached.
|
|
func (c Client) newRetryTimer(maxRetry int, unit time.Duration, cap time.Duration, jitter float64, doneCh chan struct{}) <-chan int {
|
|
attemptCh := make(chan int)
|
|
|
|
// computes the exponential backoff duration according to
|
|
// https://www.awsarchitectureblog.com/2015/03/backoff.html
|
|
exponentialBackoffWait := func(attempt int) time.Duration {
|
|
// normalize jitter to the range [0, 1.0]
|
|
if jitter < NoJitter {
|
|
jitter = NoJitter
|
|
}
|
|
if jitter > MaxJitter {
|
|
jitter = MaxJitter
|
|
}
|
|
|
|
//sleep = random_between(0, min(cap, base * 2 ** attempt))
|
|
sleep := unit * time.Duration(1<<uint(attempt))
|
|
if sleep > cap {
|
|
sleep = cap
|
|
}
|
|
if jitter != NoJitter {
|
|
sleep -= time.Duration(c.random.Float64() * float64(sleep) * jitter)
|
|
}
|
|
return sleep
|
|
}
|
|
|
|
go func() {
|
|
defer close(attemptCh)
|
|
for i := 0; i < maxRetry; i++ {
|
|
select {
|
|
// Attempts start from 1.
|
|
case attemptCh <- i + 1:
|
|
case <-doneCh:
|
|
// Stop the routine.
|
|
return
|
|
}
|
|
time.Sleep(exponentialBackoffWait(i))
|
|
}
|
|
}()
|
|
return attemptCh
|
|
}
|
|
|
|
// isNetErrorRetryable - is network error retryable.
|
|
func isNetErrorRetryable(err error) bool {
|
|
if err == nil {
|
|
return false
|
|
}
|
|
switch err.(type) {
|
|
case net.Error:
|
|
switch err.(type) {
|
|
case *net.DNSError, *net.OpError, net.UnknownNetworkError:
|
|
return true
|
|
case *url.Error:
|
|
// For a URL error, where it replies back "connection closed"
|
|
// retry again.
|
|
if strings.Contains(err.Error(), "Connection closed by foreign host") {
|
|
return true
|
|
}
|
|
default:
|
|
if strings.Contains(err.Error(), "net/http: TLS handshake timeout") {
|
|
// If error is - tlsHandshakeTimeoutError, retry.
|
|
return true
|
|
} else if strings.Contains(err.Error(), "i/o timeout") {
|
|
// If error is - tcp timeoutError, retry.
|
|
return true
|
|
} else if strings.Contains(err.Error(), "connection timed out") {
|
|
// If err is a net.Dial timeout, retry.
|
|
return true
|
|
}
|
|
}
|
|
}
|
|
return false
|
|
}
|
|
|
|
// List of AWS S3 error codes which are retryable.
|
|
var retryableS3Codes = map[string]struct{}{
|
|
"RequestError": {},
|
|
"RequestTimeout": {},
|
|
"Throttling": {},
|
|
"ThrottlingException": {},
|
|
"RequestLimitExceeded": {},
|
|
"RequestThrottled": {},
|
|
"InternalError": {},
|
|
"ExpiredToken": {},
|
|
"ExpiredTokenException": {},
|
|
// Add more AWS S3 codes here.
|
|
}
|
|
|
|
// isS3CodeRetryable - is s3 error code retryable.
|
|
func isS3CodeRetryable(s3Code string) (ok bool) {
|
|
_, ok = retryableS3Codes[s3Code]
|
|
return ok
|
|
}
|
|
|
|
// List of HTTP status codes which are retryable.
|
|
var retryableHTTPStatusCodes = map[int]struct{}{
|
|
429: {}, // http.StatusTooManyRequests is not part of the Go 1.5 library, yet
|
|
http.StatusInternalServerError: {},
|
|
http.StatusBadGateway: {},
|
|
http.StatusServiceUnavailable: {},
|
|
// Add more HTTP status codes here.
|
|
}
|
|
|
|
// isHTTPStatusRetryable - is HTTP error code retryable.
|
|
func isHTTPStatusRetryable(httpStatusCode int) (ok bool) {
|
|
_, ok = retryableHTTPStatusCodes[httpStatusCode]
|
|
return ok
|
|
}
|