100 lines
3.3 KiB
Go
100 lines
3.3 KiB
Go
// Copyright 2016, Google Inc.
|
|
// 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.
|
|
|
|
package gax
|
|
|
|
import (
|
|
"context"
|
|
"strings"
|
|
"time"
|
|
)
|
|
|
|
// APICall is a user defined call stub.
|
|
type APICall func(context.Context, CallSettings) error
|
|
|
|
// Invoke calls the given APICall,
|
|
// performing retries as specified by opts, if any.
|
|
func Invoke(ctx context.Context, call APICall, opts ...CallOption) error {
|
|
var settings CallSettings
|
|
for _, opt := range opts {
|
|
opt.Resolve(&settings)
|
|
}
|
|
return invoke(ctx, call, settings, Sleep)
|
|
}
|
|
|
|
// Sleep is similar to time.Sleep, but it can be interrupted by ctx.Done() closing.
|
|
// If interrupted, Sleep returns ctx.Err().
|
|
func Sleep(ctx context.Context, d time.Duration) error {
|
|
t := time.NewTimer(d)
|
|
select {
|
|
case <-ctx.Done():
|
|
t.Stop()
|
|
return ctx.Err()
|
|
case <-t.C:
|
|
return nil
|
|
}
|
|
}
|
|
|
|
type sleeper func(ctx context.Context, d time.Duration) error
|
|
|
|
// invoke implements Invoke, taking an additional sleeper argument for testing.
|
|
func invoke(ctx context.Context, call APICall, settings CallSettings, sp sleeper) error {
|
|
var retryer Retryer
|
|
for {
|
|
err := call(ctx, settings)
|
|
if err == nil {
|
|
return nil
|
|
}
|
|
if settings.Retry == nil {
|
|
return err
|
|
}
|
|
// Never retry permanent certificate errors. (e.x. if ca-certificates
|
|
// are not installed). We should only make very few, targeted
|
|
// exceptions: many (other) status=Unavailable should be retried, such
|
|
// as if there's a network hiccup, or the internet goes out for a
|
|
// minute. This is also why here we are doing string parsing instead of
|
|
// simply making Unavailable a non-retried code elsewhere.
|
|
if strings.Contains(err.Error(), "x509: certificate signed by unknown authority") {
|
|
return err
|
|
}
|
|
if retryer == nil {
|
|
if r := settings.Retry(); r != nil {
|
|
retryer = r
|
|
} else {
|
|
return err
|
|
}
|
|
}
|
|
if d, ok := retryer.Retry(err); !ok {
|
|
return err
|
|
} else if err = sp(ctx, d); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
}
|