[chore] remove custom Host implementation (open-telemetry#31526)

This removes a custom Host implementation in favor of using ReportStatus
to check for errors.

extension/observer/ecsobserver/extension_test.go

@@ -6,7 +6,6 @@ package ecsobserver
 import (
  "context"
  "runtime"
- "sync"
  "testing"
  "time"
 
@@ -20,49 +19,6 @@ import (
  "github.com/open-telemetry/opentelemetry-collector-contrib/extension/observer/ecsobserver/internal/ecsmock"
 )
 
-// inspectErrorHost implements component.Host.
-// btw: I only find assertNoErrorHost in other components, seems there is no exported util struct.
-type inspectErrorHost struct {
- component.Host
-
- // Why we need a mutex here? Our extension only has one go routine so it seems
- // we don't need to protect the error as our extension is the only component for this 'host'.
- // But without the lock the test actually fails on race detector.
- // There is no actual concurrency in our test, when we read the error in test assertion,
- // we know the extension has already stopped because we provided invalided config and waited long enough.
- // However, (I assume) from race detector's perspective, race between a stopped goroutine and a running one
- // is same as two running goroutines. A goroutine's stop condition is uncertain at runtime, and the data
- // access order may varies, goroutine A can stop before B in first run and reverse in next run.
- // As long as there is some read/write of one memory area without protection from multiple go routines,
- // it means the code can have data race, but it does not mean this race always happen.
- // In our case, the race never happens because we hard coded the sleep time of two go routines.
- //
- // btw: assertNoErrorHost does not have mutex because it never saves the error. Its ReportFatalError
- // just call assertion and forget about nil error. For unexpected error it call helpers to fail the test
- // and those helper func all have mutex. https://golang.org/src/testing/testing.go
- mu sync.Mutex
- err error
-}
-
-func newInspectErrorHost() component.Host {
- return &inspectErrorHost{
- Host: componenttest.NewNopHost(),
- }
-}
-
-func (h *inspectErrorHost) ReportFatalError(err error) {
- h.mu.Lock()
- h.err = err
- h.mu.Unlock()
-}
-
-func (h *inspectErrorHost) getError() error {
- h.mu.Lock()
- cp := h.err
- h.mu.Unlock()
- return cp
-}
-
 // Simply start and stop, the actual test logic is in sd_test.go until we implement the ListWatcher interface.
 // In that case sd itself does not use timer and relies on caller to trigger List.
 func TestExtensionStartStop(t *testing.T) {
@@ -71,15 +27,18 @@ func TestExtensionStartStop(t *testing.T) {
  "https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/4042")
  }
  refreshInterval := 100 * time.Millisecond
- waitDuration := 2 * refreshInterval
 
  createTestExt := func(c *ecsmock.Cluster, output string) extension.Extension {
  f := newTestTaskFetcher(t, c)
  cfg := createDefaultConfig()
  sdCfg := cfg.(*Config)
  sdCfg.RefreshInterval = refreshInterval
  sdCfg.ResultFile = output
- ext, err := createExtensionWithFetcher(extensiontest.NewNopCreateSettings(), sdCfg, f)
+ cs := extensiontest.NewNopCreateSettings()
+ cs.ReportStatus = func(event *component.StatusEvent) {
+ require.NoError(t, event.Err())
+ }
+ ext, err := createExtensionWithFetcher(cs, sdCfg, f)
  require.NoError(t, err)
  return ext
  }
@@ -88,10 +47,7 @@ func TestExtensionStartStop(t *testing.T) {
  c := ecsmock.NewCluster()
  ext := createTestExt(c, "testdata/ut_ext_noop.actual.yaml")
  require.IsType(t, &ecsObserver{}, ext)
- host := newInspectErrorHost()
- require.NoError(t, ext.Start(context.TODO(), host))
- time.Sleep(waitDuration)
- require.NoError(t, host.(*inspectErrorHost).getError())
+ require.NoError(t, ext.Start(context.TODO(), componenttest.NewNopHost()))
  require.NoError(t, ext.Shutdown(context.TODO()))
  })