Piotr Tabor 45b1e6b470 ClientV3: Ordering: Fix the ordering test such it does not fail.
The test depended on very subtle timing semantic and on properties of
'copied' clients.

https://travis-ci.com/github/etcd-io/etcd/jobs/486191449

Examplar failure:
```
{"level":"warn","ts":"2021-02-25T12:34:47.894Z","caller":"v3/retry_interceptor.go:62","msg":"retrying of unary invoker failed","target":"etcd-endpoints://0xc0000d6fc0/#initially=[unix://localhost:86269902489114839060]","attempt":1,"error":"rpc error: code = Unavailable desc = etcdserver: rpc not supported for learner"}
{"level":"warn","ts":"2021-02-25T12:34:48.163Z","caller":"v3/retry_interceptor.go:62","msg":"retrying of unary invoker failed","target":"etcd-endpoints://0xc00035a000/#initially=[unix://localhost:78285857058450835940]","attempt":0,"error":"rpc error: code = FailedPrecondition desc = etcdserver: not leader"}
{"level":"info","ts":"2021-02-25T12:34:48.255Z","caller":"v3/maintenance.go:211","msg":"opened snapshot stream; downloading"}
{"level":"warn","ts":"2021-02-25T12:34:48.255Z","caller":"v3/maintenance.go:221","msg":"failed to receive from snapshot stream; closing","error":"rpc error: code = Canceled desc = context canceled"}
{"level":"info","ts":"2021-02-25T12:34:48.255Z","caller":"v3/maintenance.go:211","msg":"opened snapshot stream; downloading"}
{"level":"info","ts":"2021-02-25T12:34:50.255Z","caller":"v3/maintenance.go:219","msg":"completed snapshot read; closing"}
{"level":"info","ts":"2021-02-25T12:34:51.717Z","caller":"v3/maintenance.go:211","msg":"opened snapshot stream; downloading"}
{"level":"warn","ts":"2021-02-25T12:34:52.017Z","caller":"v3/maintenance.go:221","msg":"failed to receive from snapshot stream; closing","error":"rpc error: code = Canceled desc = context canceled"}
{"level":"info","ts":"2021-02-25T12:34:52.018Z","caller":"v3/maintenance.go:211","msg":"opened snapshot stream; downloading"}
{"level":"warn","ts":"2021-02-25T12:34:53.018Z","caller":"v3/maintenance.go:221","msg":"failed to receive from snapshot stream; closing","error":"rpc error: code = DeadlineExceeded desc = context deadline exceeded"}
--- FAIL: TestEndpointSwitchResolvesViolation (10.12s)
    ordering_util_test.go:81: failed to resolve order violation etcdclient: no cluster members have a revision higher than the previously received revision
```
2021-02-25 22:15:13 +01:00

43 lines
1.6 KiB
Go

// Copyright 2017 The etcd Authors
//
// 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 ordering
import (
"errors"
"sync/atomic"
"go.etcd.io/etcd/client/v3"
)
type OrderViolationFunc func(op clientv3.Op, resp clientv3.OpResponse, prevRev int64) error
var ErrNoGreaterRev = errors.New("etcdclient: no cluster members have a revision higher than the previously received revision")
func NewOrderViolationSwitchEndpointClosure(c *clientv3.Client) OrderViolationFunc {
violationCount := int32(0)
return func(_ clientv3.Op, _ clientv3.OpResponse, _ int64) error {
// Each request is assigned by round-robin load-balancer's picker to a different
// endpoints. If we cycled them 5 times (even with some level of concurrency),
// with high probability no endpoint points on a member with fresh data.
// TODO: Ideally we should track members (resp.opp.Header) that returned
// stale result and explicitly temporarily disable them in 'picker'.
if atomic.LoadInt32(&violationCount) > int32(5*len(c.Endpoints())) {
return ErrNoGreaterRev
}
atomic.AddInt32(&violationCount, 1)
return nil
}
}