mirror of https://github.com/restic/restic.git
121 lines
3.7 KiB
Go
121 lines
3.7 KiB
Go
// Copyright 2016 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.
|
|
|
|
package pubsub
|
|
|
|
import (
|
|
"fmt"
|
|
"math"
|
|
"strings"
|
|
|
|
pb "google.golang.org/genproto/googleapis/pubsub/v1"
|
|
"google.golang.org/grpc/codes"
|
|
"google.golang.org/grpc/status"
|
|
)
|
|
|
|
// maxPayload is the maximum number of bytes to devote to actual ids in
|
|
// acknowledgement or modifyAckDeadline requests. A serialized
|
|
// AcknowledgeRequest proto has a small constant overhead, plus the size of the
|
|
// subscription name, plus 3 bytes per ID (a tag byte and two size bytes). A
|
|
// ModifyAckDeadlineRequest has an additional few bytes for the deadline. We
|
|
// don't know the subscription name here, so we just assume the size exclusive
|
|
// of ids is 100 bytes.
|
|
//
|
|
// With gRPC there is no way for the client to know the server's max message size (it is
|
|
// configurable on the server). We know from experience that it
|
|
// it 512K.
|
|
const (
|
|
maxPayload = 512 * 1024
|
|
reqFixedOverhead = 100
|
|
overheadPerID = 3
|
|
maxSendRecvBytes = 20 * 1024 * 1024 // 20M
|
|
)
|
|
|
|
func convertMessages(rms []*pb.ReceivedMessage) ([]*Message, error) {
|
|
msgs := make([]*Message, 0, len(rms))
|
|
for i, m := range rms {
|
|
msg, err := toMessage(m)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("pubsub: cannot decode the retrieved message at index: %d, message: %+v", i, m)
|
|
}
|
|
msgs = append(msgs, msg)
|
|
}
|
|
return msgs, nil
|
|
}
|
|
|
|
func trunc32(i int64) int32 {
|
|
if i > math.MaxInt32 {
|
|
i = math.MaxInt32
|
|
}
|
|
return int32(i)
|
|
}
|
|
|
|
// Logic from https://github.com/GoogleCloudPlatform/google-cloud-java/blob/master/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/StatusUtil.java.
|
|
func isRetryable(err error) bool {
|
|
s, ok := status.FromError(err)
|
|
if !ok { // includes io.EOF, normal stream close, which causes us to reopen
|
|
return true
|
|
}
|
|
switch s.Code() {
|
|
case codes.DeadlineExceeded, codes.Internal, codes.Canceled, codes.ResourceExhausted:
|
|
return true
|
|
case codes.Unavailable:
|
|
return !strings.Contains(s.Message(), "Server shutdownNow invoked")
|
|
default:
|
|
return false
|
|
}
|
|
}
|
|
|
|
// Split req into a prefix that is smaller than maxSize, and a remainder.
|
|
func splitRequest(req *pb.StreamingPullRequest, maxSize int) (prefix, remainder *pb.StreamingPullRequest) {
|
|
const int32Bytes = 4
|
|
|
|
// Copy all fields before splitting the variable-sized ones.
|
|
remainder = &pb.StreamingPullRequest{}
|
|
*remainder = *req
|
|
// Split message so it isn't too big.
|
|
size := reqFixedOverhead
|
|
i := 0
|
|
for size < maxSize && (i < len(req.AckIds) || i < len(req.ModifyDeadlineAckIds)) {
|
|
if i < len(req.AckIds) {
|
|
size += overheadPerID + len(req.AckIds[i])
|
|
}
|
|
if i < len(req.ModifyDeadlineAckIds) {
|
|
size += overheadPerID + len(req.ModifyDeadlineAckIds[i]) + int32Bytes
|
|
}
|
|
i++
|
|
}
|
|
|
|
min := func(a, b int) int {
|
|
if a < b {
|
|
return a
|
|
}
|
|
return b
|
|
}
|
|
|
|
j := i
|
|
if size > maxSize {
|
|
j--
|
|
}
|
|
k := min(j, len(req.AckIds))
|
|
remainder.AckIds = req.AckIds[k:]
|
|
req.AckIds = req.AckIds[:k]
|
|
k = min(j, len(req.ModifyDeadlineAckIds))
|
|
remainder.ModifyDeadlineAckIds = req.ModifyDeadlineAckIds[k:]
|
|
remainder.ModifyDeadlineSeconds = req.ModifyDeadlineSeconds[k:]
|
|
req.ModifyDeadlineAckIds = req.ModifyDeadlineAckIds[:k]
|
|
req.ModifyDeadlineSeconds = req.ModifyDeadlineSeconds[:k]
|
|
return req, remainder
|
|
}
|