services: refactor test WS reader

1. Replace isFinished atomic variable with a channel, no functional changes
   here, just use more common way as all our services do.

2. Do not check erors from SetReadDeadline and ReadMessage on exit. It
   seems to be not quite right because connection is not closed by this
   moment, and thus, these error checks are racy.
3. Add read timeout for the message reader. It is needed because some
   tests may leave message unread in the end which results in hanging
   test cleanup.
4. Add drain loop to message reader in order not to block WS reader on
   sending message.

Ref. https://github.com/nspcc-dev/neo-go/pull/3392#issuecomment-2031590403.
It's clear that TestBadSubUnsub is hanging on test cleanup, in
particular, on attempt to wait for wsRead routine to exit. The only
place where wsRead routine may hang is sending to msgCh in case if
receiver is not going to read from this channel:
```
2024-04-02T08:14:51.4957621Z goroutine 14329 [chan receive]:
2024-04-02T08:14:51.4958010Z github.com/nspcc-dev/neo-go/pkg/services/rpcsrv.initCleanServerAndWSClient.func1()
2024-04-02T08:14:51.4958344Z 	D:/a/neo-go/neo-go/pkg/services/rpcsrv/subscription_test.go:80 +0x71
2024-04-02T08:14:51.4958457Z testing.(*common).Cleanup.func1()
2024-04-02T08:14:51.4958757Z 	C:/hostedtoolcache/windows/go/1.22.1/x64/src/testing/testing.go:1175 +0x17a
2024-04-02T08:14:51.4958903Z testing.(*common).runCleanup(0xc002cf5860, 0x0)
2024-04-02T08:14:51.4959193Z 	C:/hostedtoolcache/windows/go/1.22.1/x64/src/testing/testing.go:1353 +0x262
2024-04-02T08:14:51.4959291Z testing.tRunner.func2()
2024-04-02T08:14:51.4959566Z 	C:/hostedtoolcache/windows/go/1.22.1/x64/src/testing/testing.go:1683 +0x51
2024-04-02T08:14:51.4959695Z testing.tRunner(0xc002cf5860, 0x141687410)
2024-04-02T08:14:51.4959976Z 	C:/hostedtoolcache/windows/go/1.22.1/x64/src/testing/testing.go:1695 +0x25e
2024-04-02T08:14:51.4960115Z created by testing.(*T).Run in goroutine 1
2024-04-02T08:14:51.4960385Z 	C:/hostedtoolcache/windows/go/1.22.1/x64/src/testing/testing.go:1742 +0x826
```

Signed-off-by: Anna Shaleva <shaleva.ann@nspcc.ru>
This commit is contained in:
Anna Shaleva 2024-04-03 12:29:04 +03:00
parent b947d09552
commit 29deba45ca

View file

@ -4,7 +4,6 @@ import (
"encoding/json"
"fmt"
"strings"
"sync/atomic"
"testing"
"time"
@ -20,21 +19,36 @@ import (
const testOverflow = false
func wsReader(t *testing.T, ws *websocket.Conn, msgCh chan<- []byte, isFinished *atomic.Bool, readerToExitCh chan struct{}) {
for !isFinished.Load() {
err := ws.SetReadDeadline(time.Now().Add(5 * time.Second))
if isFinished.Load() {
require.Error(t, err)
break
func wsReader(t *testing.T, ws *websocket.Conn, msgCh chan<- []byte, readerStopCh chan struct{}, readerToExitCh chan struct{}) {
readLoop:
for {
select {
case <-readerStopCh:
break readLoop
default:
err := ws.SetReadDeadline(time.Now().Add(5 * time.Second))
select {
case <-readerStopCh:
break readLoop
default:
require.NoError(t, err)
}
_, body, err := ws.ReadMessage()
select {
case <-readerStopCh:
break readLoop
default:
require.NoError(t, err)
}
select {
case msgCh <- body:
case <-time.After(10 * time.Second):
t.Log("exiting wsReader loop: unable to send response to receiver")
break readLoop
}
}
require.NoError(t, err)
_, body, err := ws.ReadMessage()
if isFinished.Load() {
require.Error(t, err)
break
}
require.NoError(t, err)
msgCh <- body
}
close(readerToExitCh)
}
@ -69,14 +83,22 @@ func initCleanServerAndWSClient(t *testing.T, startNetworkServer ...bool) (*core
// Use buffered channel to read server's messages and then read expected
// responses from it.
respMsgs := make(chan []byte, 16)
finishedFlag := &atomic.Bool{}
readerStopCh := make(chan struct{})
readerToExitCh := make(chan struct{})
go wsReader(t, ws, respMsgs, finishedFlag, readerToExitCh)
go wsReader(t, ws, respMsgs, readerStopCh, readerToExitCh)
if len(startNetworkServer) != 0 && startNetworkServer[0] {
rpcSrv.coreServer.Start()
}
t.Cleanup(func() {
finishedFlag.Store(true)
drainLoop:
for {
select {
case <-respMsgs:
default:
break drainLoop
}
}
close(readerStopCh)
<-readerToExitCh
ws.Close()
if len(startNetworkServer) != 0 && startNetworkServer[0] {