fix(http_listener_v2): fix panic on close (#10132)

plugins/inputs/http_listener_v2/http_listener_v2.go

@@ -4,6 +4,7 @@ import (
 	"compress/gzip"
 	"crypto/subtle"
 	"crypto/tls"
+	"errors"
 	"io"
 	"net"
 	"net/http"
@@ -50,12 +51,15 @@ type HTTPListenerV2 struct {
 	BasicUsername  string            `toml:"basic_username"`
 	BasicPassword  string            `toml:"basic_password"`
 	HTTPHeaderTags map[string]string `toml:"http_header_tags"`
+
 	tlsint.ServerConfig
+	tlsConf *tls.Config
 
 	TimeFunc
 	Log telegraf.Logger
 
 	wg    sync.WaitGroup
+	close chan struct{}
 
 	listener net.Listener
 
@@ -154,17 +158,48 @@ func (h *HTTPListenerV2) Start(acc telegraf.Accumulator) error {
 
 	h.acc = acc
 
-	tlsConf, err := h.ServerConfig.TLSConfig()
+	server := h.createHTTPServer()
-	if err != nil {
+
-		return err
+	h.wg.Add(1)
+	go func() {
+		defer h.wg.Done()
+		if err := server.Serve(h.listener); err != nil {
+			if !errors.Is(err, net.ErrClosed) {
+				h.Log.Errorf("Serve failed: %v", err)
+			}
+			close(h.close)
+		}
+	}()
+
+	h.Log.Infof("Listening on %s", h.listener.Addr().String())
+
+	return nil
 }
 
-	server := &http.Server{
+func (h *HTTPListenerV2) createHTTPServer() *http.Server {
+	return &http.Server{
 		Addr:         h.ServiceAddress,
 		Handler:      h,
 		ReadTimeout:  time.Duration(h.ReadTimeout),
 		WriteTimeout: time.Duration(h.WriteTimeout),
-		TLSConfig:    tlsConf,
+		TLSConfig:    h.tlsConf,
+	}
+}
+
+// Stop cleans up all resources
+func (h *HTTPListenerV2) Stop() {
+	if h.listener != nil {
+		// Ignore the returned error as we cannot do anything about it anyway
+		//nolint:errcheck,revive
+		h.listener.Close()
+	}
+	h.wg.Wait()
+}
+
+func (h *HTTPListenerV2) Init() error {
+	tlsConf, err := h.ServerConfig.TLSConfig()
+	if err != nil {
+		return err
 	}
 
 	var listener net.Listener
@@ -176,32 +211,13 @@ func (h *HTTPListenerV2) Start(acc telegraf.Accumulator) error {
 	if err != nil {
 		return err
 	}
+	h.tlsConf = tlsConf
 	h.listener = listener
 	h.Port = listener.Addr().(*net.TCPAddr).Port
 
-	h.wg.Add(1)
-	go func() {
-		defer h.wg.Done()
-		if err := server.Serve(h.listener); err != nil {
-			h.Log.Errorf("Serve failed: %v", err)
-		}
-	}()
-
-	h.Log.Infof("Listening on %s", listener.Addr().String())
-
 	return nil
 }
 
-// Stop cleans up all resources
-func (h *HTTPListenerV2) Stop() {
-	if h.listener != nil {
-		// Ignore the returned error as we cannot do anything about it anyway
-		//nolint:errcheck,revive
-		h.listener.Close()
-	}
-	h.wg.Wait()
-}
-
 func (h *HTTPListenerV2) ServeHTTP(res http.ResponseWriter, req *http.Request) {
 	handler := h.serveWrite
 
@@ -213,6 +229,13 @@ func (h *HTTPListenerV2) ServeHTTP(res http.ResponseWriter, req *http.Request) {
 }
 
 func (h *HTTPListenerV2) serveWrite(res http.ResponseWriter, req *http.Request) {
+	select {
+	case <-h.close:
+		res.WriteHeader(http.StatusGone)
+		return
+	default:
+	}
+
 	// Check that the content length is not too large for us to handle.
 	if req.ContentLength > int64(h.MaxBodySize) {
 		if err := tooLarge(res); err != nil {
@@ -393,6 +416,7 @@ func init() {
 			Paths:          []string{"/telegraf"},
 			Methods:        []string{"POST", "PUT"},
 			DataSource:     body,
+			close:          make(chan struct{}),
 		}
 	})
 }

plugins/inputs/http_listener_v2/http_listener_v2_test.go

@@ -56,6 +56,7 @@ func newTestHTTPListenerV2() *HTTPListenerV2 {
 		TimeFunc:       time.Now,
 		MaxBodySize:    config.Size(70000),
 		DataSource:     "body",
+		close:          make(chan struct{}),
 	}
 	return listener
 }
@@ -78,6 +79,7 @@ func newTestHTTPSListenerV2() *HTTPListenerV2 {
 		Parser:         parser,
 		ServerConfig:   *pki.TLSServerConfig(),
 		TimeFunc:       time.Now,
+		close:          make(chan struct{}),
 	}
 
 	return listener
@@ -117,10 +119,10 @@ func TestInvalidListenerConfig(t *testing.T) {
 		TimeFunc:       time.Now,
 		MaxBodySize:    config.Size(70000),
 		DataSource:     "body",
+		close:          make(chan struct{}),
 	}
 
-	acc := &testutil.Accumulator{}
+	require.Error(t, listener.Init())
-	require.Error(t, listener.Start(acc))
 
 	// Stop is called when any ServiceInput fails to start; it must succeed regardless of state
 	listener.Stop()
@@ -131,6 +133,7 @@ func TestWriteHTTPSNoClientAuth(t *testing.T) {
 	listener.TLSAllowedCACerts = nil
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -155,6 +158,7 @@ func TestWriteHTTPSWithClientAuth(t *testing.T) {
 	listener := newTestHTTPSListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -169,6 +173,7 @@ func TestWriteHTTPBasicAuth(t *testing.T) {
 	listener := newTestHTTPAuthListener()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -187,6 +192,7 @@ func TestWriteHTTP(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -237,6 +243,7 @@ func TestWriteHTTPWithPathTag(t *testing.T) {
 	listener.PathTag = true
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -260,6 +267,7 @@ func TestWriteHTTPWithMultiplePaths(t *testing.T) {
 	listener.PathTag = true
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -292,6 +300,7 @@ func TestWriteHTTPNoNewline(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -319,9 +328,11 @@ func TestWriteHTTPExactMaxBodySize(t *testing.T) {
 		Parser:         parser,
 		MaxBodySize:    config.Size(len(hugeMetric)),
 		TimeFunc:       time.Now,
+		close:          make(chan struct{}),
 	}
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -342,9 +353,11 @@ func TestWriteHTTPVerySmallMaxBody(t *testing.T) {
 		Parser:         parser,
 		MaxBodySize:    config.Size(4096),
 		TimeFunc:       time.Now,
+		close:          make(chan struct{}),
 	}
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -359,6 +372,8 @@ func TestWriteHTTPGzippedData(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -391,6 +406,7 @@ func TestWriteHTTPSnappyData(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -429,6 +445,7 @@ func TestWriteHTTPHighTraffic(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -464,6 +481,7 @@ func TestReceive404ForInvalidEndpoint(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -478,6 +496,7 @@ func TestWriteHTTPInvalid(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -492,6 +511,7 @@ func TestWriteHTTPEmpty(t *testing.T) {
 	listener := newTestHTTPListenerV2()
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -507,6 +527,7 @@ func TestWriteHTTPTransformHeaderValuesToTagsSingleWrite(t *testing.T) {
 	listener.HTTPHeaderTags = map[string]string{"Present_http_header_1": "presentMeasurementKey1", "present_http_header_2": "presentMeasurementKey2", "NOT_PRESENT_HEADER": "notPresentMeasurementKey"}
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -545,6 +566,7 @@ func TestWriteHTTPTransformHeaderValuesToTagsBulkWrite(t *testing.T) {
 	listener.HTTPHeaderTags = map[string]string{"Present_http_header_1": "presentMeasurementKey1", "Present_http_header_2": "presentMeasurementKey2", "NOT_PRESENT_HEADER": "notPresentMeasurementKey"}
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -576,6 +598,7 @@ func TestWriteHTTPQueryParams(t *testing.T) {
 	listener.Parser = parser
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()
 
@@ -597,6 +620,7 @@ func TestWriteHTTPFormData(t *testing.T) {
 	listener.Parser = parser
 
 	acc := &testutil.Accumulator{}
+	require.NoError(t, listener.Init())
 	require.NoError(t, listener.Start(acc))
 	defer listener.Stop()