Fix duplicate tags in TCP/UDP logs

pkg/logs/tailers/socket/tailer.go

@@ -98,8 +98,7 @@ func (t *Tailer) readForever() {
  log.Warnf("Couldn't read message from connection: %v", err)
  return
  }
- copiedTags := make([]string, len(t.source.Config.Tags))
- copy(copiedTags, t.source.Config.Tags)
+ msg := decoder.NewInput(data)
  if ipAddress != "" && pkgconfigsetup.Datadog().GetBool("logs_config.use_sourcehost_tag") {
  lastColonIndex := strings.LastIndex(ipAddress, ":")
  var ipAddressWithoutPort string
@@ -109,10 +108,8 @@ func (t *Tailer) readForever() {
  ipAddressWithoutPort = ipAddress
  }
  sourceHostTag := fmt.Sprintf("source_host:%s", ipAddressWithoutPort)
- copiedTags = append(copiedTags, sourceHostTag)
+ msg.ParsingExtra.Tags = append(msg.ParsingExtra.Tags, sourceHostTag)
  }
- msg := decoder.NewInput(data)
- msg.ParsingExtra.Tags = append(msg.ParsingExtra.Tags, copiedTags...)
  t.decoder.InputChan <- msg
  }
  }

pkg/logs/tailers/socket/tailer_test.go

@@ -58,6 +58,26 @@ func TestReadShouldFailWithError(t *testing.T) {
  tailer.Stop()
 }
 
+func TestDuplicateTags(t *testing.T) {
+ msgChan := make(chan *message.Message)
+ r, w := net.Pipe()
+ logsConfig := &config.LogsConfig{
+ Tags: []string{"test:tag"},
+ }
+ logSource := sources.NewLogSource("test-source", logsConfig)
+
+ tailer := NewTailer(logSource, r, msgChan, read)
+ tailer.Start()
+
+ var msg *message.Message
+
+ w.Write([]byte("foo\n"))
+ msg = <-msgChan
+ assert.Equal(t, []string{"test:tag"}, msg.Tags())
+
+ tailer.Stop()
+}
+
 func read(tailer *Tailer) ([]byte, string, error) {
  inBuf := make([]byte, 4096)
  n, err := tailer.Conn.Read(inBuf)

releasenotes/notes/fix-duplicate-tags-e97e8eeb6492235f.yaml

@@ -0,0 +1,12 @@
+# Each section from every release note are combined when the
+# CHANGELOG.rst is rendered. So the text needs to be worded so that
+# it does not depend on any information only available in another
+# section. This may mean repeating some details, but each section
+# must be readable independently of the other.
+#
+# Each section note must be formatted as reStructuredText.
+---
+fixes:
+ - |
+ Fix duplicate tags in UDP/TCP logs.
+