From 1b81d8f5427827b4cbdf53f635943c223650c78b Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@victoriametrics.com>
Date: Fri, 27 Jan 2023 13:24:30 -0800
Subject: [PATCH] lib/netutil: move IsTrivialNetworkError() function there,
 since it is used in multiple places across the code

---
 app/vmselect/bufferedwriter/bufferedwriter.go | 16 ++++------------
 lib/httpserver/httpserver.go                  | 14 +++-----------
 lib/netutil/netutil.go                        | 15 +++++++++++++++
 3 files changed, 22 insertions(+), 23 deletions(-)
 create mode 100644 lib/netutil/netutil.go

diff --git a/app/vmselect/bufferedwriter/bufferedwriter.go b/app/vmselect/bufferedwriter/bufferedwriter.go
index a06e59ecb..5e25d6ab3 100644
--- a/app/vmselect/bufferedwriter/bufferedwriter.go
+++ b/app/vmselect/bufferedwriter/bufferedwriter.go
@@ -4,8 +4,9 @@ import (
 	"bufio"
 	"fmt"
 	"io"
-	"strings"
 	"sync"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/netutil"
 )
 
 // Get returns buffered writer for the given w.
@@ -63,7 +64,7 @@ func (bw *Writer) Write(p []byte) (int, error) {
 		return 0, bw.err
 	}
 	n, err := bw.bw.Write(p)
-	if err != nil && !isTrivialNetworkError(err) {
+	if err != nil && !netutil.IsTrivialNetworkError(err) {
 		bw.err = fmt.Errorf("cannot send %d bytes to client: %w", len(p), err)
 	}
 	return n, bw.err
@@ -76,7 +77,7 @@ func (bw *Writer) Flush() error {
 	if bw.err != nil {
 		return bw.err
 	}
-	if err := bw.bw.Flush(); err != nil && !isTrivialNetworkError(err) {
+	if err := bw.bw.Flush(); err != nil && !netutil.IsTrivialNetworkError(err) {
 		bw.err = fmt.Errorf("cannot flush data to client: %w", err)
 	}
 	return bw.err
@@ -88,12 +89,3 @@ func (bw *Writer) Error() error {
 	defer bw.lock.Unlock()
 	return bw.err
 }
-
-func isTrivialNetworkError(err error) bool {
-	// Suppress trivial network errors, which could occur at remote side.
-	s := err.Error()
-	if strings.Contains(s, "broken pipe") || strings.Contains(s, "reset by peer") {
-		return true
-	}
-	return false
-}
diff --git a/lib/httpserver/httpserver.go b/lib/httpserver/httpserver.go
index 1668489ef..09a54c505 100644
--- a/lib/httpserver/httpserver.go
+++ b/lib/httpserver/httpserver.go
@@ -199,7 +199,7 @@ func gzipHandler(s *server, rh RequestHandler) http.HandlerFunc {
 		w = maybeGzipResponseWriter(w, r)
 		handlerWrapper(s, w, r, rh)
 		if zrw, ok := w.(*gzipResponseWriter); ok {
-			if err := zrw.Close(); err != nil && !isTrivialNetworkError(err) {
+			if err := zrw.Close(); err != nil && !netutil.IsTrivialNetworkError(err) {
 				logger.Warnf("gzipResponseWriter.Close: %s", err)
 			}
 		}
@@ -503,10 +503,10 @@ func (zrw *gzipResponseWriter) Flush() {
 		_, _ = zrw.Write(nil)
 	}
 	if !zrw.disableCompression {
-		if err := zrw.bw.Flush(); err != nil && !isTrivialNetworkError(err) {
+		if err := zrw.bw.Flush(); err != nil && !netutil.IsTrivialNetworkError(err) {
 			logger.Warnf("gzipResponseWriter.Flush (buffer): %s", err)
 		}
-		if err := zrw.zw.Flush(); err != nil && !isTrivialNetworkError(err) {
+		if err := zrw.zw.Flush(); err != nil && !netutil.IsTrivialNetworkError(err) {
 			logger.Warnf("gzipResponseWriter.Flush (gzip): %s", err)
 		}
 	}
@@ -643,14 +643,6 @@ func (e *ErrorWithStatusCode) Error() string {
 	return e.Err.Error()
 }
 
-func isTrivialNetworkError(err error) bool {
-	s := err.Error()
-	if strings.Contains(s, "broken pipe") || strings.Contains(s, "reset by peer") {
-		return true
-	}
-	return false
-}
-
 // IsTLS indicates is tls enabled or not
 func IsTLS() bool {
 	return *tlsEnable
diff --git a/lib/netutil/netutil.go b/lib/netutil/netutil.go
new file mode 100644
index 000000000..91f72296c
--- /dev/null
+++ b/lib/netutil/netutil.go
@@ -0,0 +1,15 @@
+package netutil
+
+import (
+	"strings"
+)
+
+// IsTrivialNetworkError returns true if the err can be ignored during logging.
+func IsTrivialNetworkError(err error) bool {
+	// Suppress trivial network errors, which could occur at remote side.
+	s := err.Error()
+	if strings.Contains(s, "broken pipe") || strings.Contains(s, "reset by peer") {
+		return true
+	}
+	return false
+}