Revert "[Backport 7.58.x] Fix duplicate tags in TCP/UDP logs (#29996)"

This reverts commit 8c88cd3.

pkg/logs/tailers/socket/tailer.go

@@ -12,7 +12,7 @@ import (
 	"net"
 	"strings"
 
-	pkgconfigsetup "github.com/DataDog/datadog-agent/pkg/config/setup"
+	coreConfig "github.com/DataDog/datadog-agent/pkg/config"
 	"github.com/DataDog/datadog-agent/pkg/logs/internal/decoder"
 	"github.com/DataDog/datadog-agent/pkg/logs/internal/parsers/noop"
 	"github.com/DataDog/datadog-agent/pkg/logs/message"
@@ -98,8 +98,9 @@ func (t *Tailer) readForever() {
 				log.Warnf("Couldn't read message from connection: %v", err)
 				return
 			}
-			msg := decoder.NewInput(data)
-			if ipAddress != "" && pkgconfigsetup.Datadog().GetBool("logs_config.use_sourcehost_tag") {
+			copiedTags := make([]string, len(t.source.Config.Tags))
+			copy(copiedTags, t.source.Config.Tags)
+			if ipAddress != "" && coreConfig.Datadog().GetBool("logs_config.use_sourcehost_tag") {
 				lastColonIndex := strings.LastIndex(ipAddress, ":")
 				var ipAddressWithoutPort string
 				if lastColonIndex != -1 {
@@ -108,8 +109,10 @@ func (t *Tailer) readForever() {
 					ipAddressWithoutPort = ipAddress
 				}
 				sourceHostTag := fmt.Sprintf("source_host:%s", ipAddressWithoutPort)
-				msg.ParsingExtra.Tags = append(msg.ParsingExtra.Tags, sourceHostTag)
+				copiedTags = append(copiedTags, sourceHostTag)
 			}
+			msg := decoder.NewInput(data)
+			msg.ParsingExtra.Tags = append(msg.ParsingExtra.Tags, copiedTags...)
 			t.decoder.InputChan <- msg
 		}
 	}

pkg/logs/tailers/socket/tailer_test.go

@@ -13,7 +13,6 @@ import (
 	"github.com/stretchr/testify/assert"
 
 	"github.com/DataDog/datadog-agent/comp/logs/agent/config"
-	pkgconfigsetup "github.com/DataDog/datadog-agent/pkg/config/setup"
 	"github.com/DataDog/datadog-agent/pkg/logs/message"
 	"github.com/DataDog/datadog-agent/pkg/logs/sources"
 )
@@ -59,49 +58,6 @@ func TestReadShouldFailWithError(t *testing.T) {
 	tailer.Stop()
 }
 
-func TestSourceHostTag(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, readWithIP)
-	tailer.Start()
-
-	var msg *message.Message
-	w.Write([]byte("foo\n"))
-	msg = <-msgChan
-	assert.Equal(t, []string{"source_host:192.168.1.100", "test:tag"}, msg.Tags())
-	tailer.Stop()
-}
-
-func TestSourceHostTagFlagDisabled(t *testing.T) {
-	// Set the config flag for source_host tag to false
-	pkgconfigsetup.Datadog().BindEnvAndSetDefault("logs_config.use_sourcehost_tag", false)
-
-	// Set up test components
-	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, readWithIP)
-	tailer.Start()
-
-	var msg *message.Message
-	w.Write([]byte("foo\n"))
-	msg = <-msgChan
-
-	// Assert that only the original tag is present (source_host tag should not be added)
-	assert.Equal(t, []string{"test:tag"}, msg.Tags(), "source_host tag should not be added when flag is disabled")
-
-	tailer.Stop()
-}
-
 func read(tailer *Tailer) ([]byte, string, error) {
 	inBuf := make([]byte, 4096)
 	n, err := tailer.Conn.Read(inBuf)
@@ -110,13 +66,3 @@ func read(tailer *Tailer) ([]byte, string, error) {
 	}
 	return inBuf[:n], "", nil
 }
-
-func readWithIP(tailer *Tailer) ([]byte, string, error) {
-	inBuf := make([]byte, 4096)
-	n, err := tailer.Conn.Read(inBuf)
-	if err != nil {
-		return nil, "", err
-	}
-	mockIPAddress := "192.168.1.100:8080"
-	return inBuf[:n], mockIPAddress, nil
-}

test/new-e2e/tests/agent-metrics-logs/log-agent/utils/file_tailing_utils.go

@@ -149,7 +149,7 @@ func FetchAndFilterLogs(t *testing.T, fakeIntake *components.FakeIntake, service
 	return logs, nil
 }
 
-// CheckLogsExpected verifies the presence of expected logs, and verifies that there are no duplicate tags.
+// CheckLogsExpected verifies the presence of expected logs.
 func CheckLogsExpected(t *testing.T, fakeIntake *components.FakeIntake, service, content string, expectedTags ddtags) {
 	t.Helper()
 
@@ -160,14 +160,6 @@ func CheckLogsExpected(t *testing.T, fakeIntake *components.FakeIntake, service,
 			if assert.NotEmpty(c, logs, "Expected logs with content: '%s' not found. Instead, found: %s", content, intakeLog) {
 				t.Logf("Logs from service: '%s' with content: '%s' collected", service, content)
 				log := logs[0]
-				// Use a map to check for duplicate tags
-				seenTags := make(map[string]struct{})
-				for _, tag := range log.Tags {
-					if _, exists := seenTags[tag]; exists {
-						t.Errorf("Duplicate tag found: %s", tag)
-					}
-					seenTags[tag] = struct{}{} // Mark the tag as seen
-				}
 				for _, expectedTag := range expectedTags {
 					assert.Contains(t, log.Tags, expectedTag)
 				}