[receiver/opencensus]: check for ErrListenerClosed when reporting mul…

…tiplexer status (#34093)

Fixes #33865

---------

Signed-off-by: odubajDT <ondrej.dubaj@dynatrace.com>

.chloggen/correctness-traces.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: opencensusreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Do not report an error into resource status during receiver shutdown when the listener connection was closed.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [33865]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

receiver/opencensusreceiver/opencensus.go

@@ -113,10 +113,12 @@ func (ocr *ocReceiver) Start(ctx context.Context, host component.Host) error {
 	if !hasConsumer {
 		return errors.New("cannot start receiver: no consumers were specified")
 	}
+
 	ocr.ln, err = net.Listen(string(ocr.cfg.NetAddr.Transport), ocr.cfg.NetAddr.Endpoint)
 	if err != nil {
 		return fmt.Errorf("failed to bind to address %q: %w", ocr.cfg.NetAddr.Endpoint, err)
 	}
+
 	// Register the grpc-gateway on the HTTP server mux
 	var c context.Context
 	c, ocr.cancel = context.WithCancel(context.Background())
@@ -155,7 +157,7 @@ func (ocr *ocReceiver) Start(ctx context.Context, host component.Host) error {
 	}()
 	go func() {
 		startWG.Done()
-		if err := ocr.multiplexer.Serve(); !errors.Is(err, cmux.ErrServerClosed) && err != nil {
+		if err := ocr.multiplexer.Serve(); !errors.Is(err, cmux.ErrServerClosed) && !errors.Is(err, cmux.ErrListenerClosed) && err != nil {
 			ocr.settings.TelemetrySettings.ReportStatus(component.NewFatalErrorEvent(err))
 		}
 	}()

receiver/opencensusreceiver/opencensus_test.go

@@ -302,6 +302,89 @@ func TestStartWithoutConsumersShouldFail(t *testing.T) {
 	require.Error(t, r.Start(context.Background(), componenttest.NewNopHost()))
 }
 
+func TestStartListenerClosed(t *testing.T) {
+
+	addr := testutil.GetAvailableLocalAddress(t)
+
+	// Set the buffer count to 1 to make it flush the test span immediately.
+	sink := new(consumertest.TracesSink)
+	cfg := &Config{
+		ServerConfig: configgrpc.ServerConfig{
+			NetAddr: confignet.AddrConfig{
+				Endpoint:  addr,
+				Transport: "tcp",
+			},
+		},
+	}
+	ocr := newOpenCensusReceiver(cfg, sink, nil, receivertest.NewNopSettings())
+
+	ctx := context.Background()
+
+	// start receiver
+	err := ocr.Start(ctx, componenttest.NewNopHost())
+	require.NoError(t, err, "Failed to start trace receiver: %v", err)
+
+	url := fmt.Sprintf("http://%s/v1/trace", addr)
+
+	traceJSON := []byte(`
+	{
+	   "node":{"identifier":{"hostName":"testHost"}},
+	   "spans":[
+	      {
+	          "traceId":"W47/95gDgQPSabYzgT/GDA==",
+	          "spanId":"7uGbfsPBsXM=",
+	          "name":{"value":"testSpan"},
+	          "startTime":"2018-12-13T14:51:00Z",
+	          "endTime":"2018-12-13T14:51:01Z",
+	          "attributes": {
+	            "attributeMap": {
+	              "attr1": {"intValue": "55"}
+	            }
+	          }
+	      }
+	   ]
+	}`)
+
+	// send request to verify listener is working
+	req, err := http.NewRequest(http.MethodPost, url, bytes.NewBuffer(traceJSON))
+	require.NoError(t, err, "Error creating trace POST request: %v", err)
+	req.Header.Set("Content-Type", "application/json")
+
+	client := &http.Client{}
+	defer client.CloseIdleConnections()
+	resp, err := client.Do(req)
+	require.NoError(t, err, "Error posting trace to grpc-gateway server: %v", err)
+
+	defer func() {
+		require.NoError(t, resp.Body.Close())
+	}()
+
+	respBytes, err := io.ReadAll(resp.Body)
+	require.NoError(t, err)
+	respStr := string(respBytes)
+
+	assert.Equal(t, http.StatusOK, resp.StatusCode)
+	assert.Empty(t, respStr)
+
+	// stop the listener
+	ocr.ln.Close()
+
+	// verify trace was sent
+	got := sink.AllTraces()
+	require.Len(t, got, 1)
+	require.Equal(t, 1, got[0].ResourceSpans().Len())
+	gotNode, gotResource, gotSpans := opencensus.ResourceSpansToOC(got[0].ResourceSpans().At(0))
+
+	wantNode := &commonpb.Node{Identifier: &commonpb.ProcessIdentifier{HostName: "testHost"}}
+	wantResource := &resourcepb.Resource{}
+	assert.True(t, proto.Equal(wantNode, gotNode))
+	assert.True(t, proto.Equal(wantResource, gotResource))
+	require.Len(t, gotSpans, 1)
+
+	// stop the receiver to verify it's not blocked by the closed listener
+	require.NoError(t, ocr.Shutdown(ctx))
+}
+
 func tempSocketName(t *testing.T) string {
 	tmpfile, err := os.CreateTemp("", "sock")
 	require.NoError(t, err)