cri-o/vendor/cloud.google.com/go/bigtable/internal/gax/invoke.go
Jacek J. Łakis bf51655a7b vendor: Update vendoring for the exec client and server implementations
Signed-off-by: Jacek J. Łakis <jacek.lakis@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2017-04-24 18:38:41 +02:00

84 lines
2.4 KiB
Go

/*
Copyright 2015 Google Inc. All Rights Reserved.
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.
*/
// This is ia snapshot from github.com/googleapis/gax-go with minor modifications.
package gax
import (
"math/rand"
"time"
"golang.org/x/net/context"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"log"
"os"
)
var logger *log.Logger = log.New(os.Stderr, "", log.LstdFlags)
// A user defined call stub.
type APICall func(context.Context) error
// scaleDuration returns the product of a and mult.
func scaleDuration(a time.Duration, mult float64) time.Duration {
ns := float64(a) * mult
return time.Duration(ns)
}
// invokeWithRetry calls stub using an exponential backoff retry mechanism
// based on the values provided in callSettings.
func invokeWithRetry(ctx context.Context, stub APICall, callSettings CallSettings) error {
retrySettings := callSettings.RetrySettings
backoffSettings := callSettings.RetrySettings.BackoffSettings
delay := backoffSettings.DelayTimeoutSettings.Initial
for {
// If the deadline is exceeded...
if ctx.Err() != nil {
return ctx.Err()
}
err := stub(ctx)
code := grpc.Code(err)
if code == codes.OK {
return nil
}
if !retrySettings.RetryCodes[code] {
return err
}
// Sleep a random amount up to the current delay
d := time.Duration(rand.Int63n(int64(delay)))
delayCtx, _ := context.WithTimeout(ctx, delay)
logger.Printf("Retryable error: %v, retrying in %v", err, d)
<-delayCtx.Done()
delay = scaleDuration(delay, backoffSettings.DelayTimeoutSettings.Multiplier)
if delay > backoffSettings.DelayTimeoutSettings.Max {
delay = backoffSettings.DelayTimeoutSettings.Max
}
}
}
// Invoke calls stub with a child of context modified by the specified options.
func Invoke(ctx context.Context, stub APICall, opts ...CallOption) error {
settings := &CallSettings{}
callOptions(opts).Resolve(settings)
if len(settings.RetrySettings.RetryCodes) > 0 {
return invokeWithRetry(ctx, stub, *settings)
}
return stub(ctx)
}