Check container symlink when a new source is scheduled (#28712)

pkg/logs/launchers/file/launcher.go

@@ -277,6 +277,10 @@ func (s *Launcher) launchTailers(source *sources.LogSource) {
 		if s.tailers.Count() >= s.tailingLimit {
 			return
 		}
+
+		if fileprovider.ShouldIgnore(s.validatePodContainerID, file) {
+			continue
+		}
 		if tailer, isTailed := s.tailers.Get(file.GetScanKey()); isTailed {
 			// the file is already tailed, update the existing tailer's source so that the tailer
 			// uses this new source going forward

pkg/logs/launchers/file/provider/file_provider.go

@@ -132,7 +132,7 @@ func (p *FileProvider) addFilesToTailList(validatePodContainerID bool, inputFile
 	// Add each file one by one up to the limit
 	for j := 0; j < len(inputFiles) && len(filesToTail) < p.filesLimit; j++ {
 		file := inputFiles[j]
-		if shouldIgnore(validatePodContainerID, file) {
+		if ShouldIgnore(validatePodContainerID, file) {
 			continue
 		}
 		filesToTail = append(filesToTail, file)
@@ -348,7 +348,7 @@ func (p *FileProvider) applyOrdering(files []*tailer.File) {
 	}
 }
 
-// shouldIgnore resolves symlinks in /var/log/containers in order to use that redirection
+// ShouldIgnore resolves symlinks in /var/log/containers in order to use that redirection
 // to validate that we will be reading a file for the correct container.
 //
 // We have to make sure that the file we just detected is tagged with the correct
@@ -361,7 +361,7 @@ func (p *FileProvider) applyOrdering(files []*tailer.File) {
 // See these links for more info:
 //   - https://github.com/kubernetes/kubernetes/issues/58638
 //   - https://github.com/fabric8io/fluent-plugin-kubernetes_metadata_filter/issues/105
-func shouldIgnore(validatePodContainerID bool, file *tailer.File) bool {
+func ShouldIgnore(validatePodContainerID bool, file *tailer.File) bool {
 	// this method needs a source config to detect whether we should ignore that file or not
 	if file == nil || file.Source == nil || file.Source.Config() == nil {
 		return false

pkg/logs/launchers/file/provider/file_provider_test.go

@@ -679,21 +679,21 @@ func TestContainerIDInContainerLogFile(t *testing.T) {
 	}
 
 	// we've found a symlink validating that the file we have just scanned is concerning the container we're currently processing for this source
-	assert.False(shouldIgnore(true, &file), "the file existing in ContainersLogsDir is pointing to the same container, scanned file should be tailed")
+	assert.False(ShouldIgnore(true, &file), "the file existing in ContainersLogsDir is pointing to the same container, scanned file should be tailed")
 
 	// now, let's change the container for which we are trying to scan files,
 	// because the symlink is pointing from another container, we should ignore
 	// that log file
 	file.Source.Config().Identifier = "1234123412341234123412341234123412341234123412341234123412341234"
-	assert.True(shouldIgnore(true, &file), "the file existing in ContainersLogsDir is not pointing to the same container, scanned file should be ignored")
+	assert.True(ShouldIgnore(true, &file), "the file existing in ContainersLogsDir is not pointing to the same container, scanned file should be ignored")
 
 	// in this scenario, no link is found in /var/log/containers, thus, we should not ignore the file
 	os.Remove("/tmp/myapp_my-namespace_myapp-abcdefabcdefabcdabcdefabcdefabcdabcdefabcdefabcdabcdefabcdefabcd.log")
-	assert.False(shouldIgnore(true, &file), "no files existing in ContainersLogsDir, we should not ignore the file we have just scanned")
+	assert.False(ShouldIgnore(true, &file), "no files existing in ContainersLogsDir, we should not ignore the file we have just scanned")
 
 	// in this scenario, the file we've found doesn't look like a container ID
 	os.Symlink("/var/log/pods/file-uuid-foo-bar.log", "/tmp/myapp_my-namespace_myapp-thisisnotacontainerIDevenifthisispointingtothecorrectfile.log")
-	assert.False(shouldIgnore(true, &file), "no container ID found, we don't want to ignore this scanned file")
+	assert.False(ShouldIgnore(true, &file), "no container ID found, we don't want to ignore this scanned file")
 }
 
 func TestContainerPathsAreCorrectlyIgnored(t *testing.T) {

releasenotes/notes/fix-short-lived-container-schedule-87fc0be81e7e160d.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:
+  - |
+    Fixed a rare issue where short-lived containers could cause 
+    logs to be sent with the wrong container ID.