Add more robust error handling for files

pkg/logs/launchers/integration/launcher.go

@@ -7,6 +7,7 @@
 package integration
 
 import (
+	"errors"
 	"math"
 	"os"
 	"path/filepath"
@@ -67,10 +68,17 @@ func NewLauncher(sources *sources.LogSources, integrationsLogsComp integrations.
 
 	logsTotalUsageSetting := datadogConfig.GetInt64("logs_config.integrations_logs_total_usage") * 1024 * 1024
 	logsUsageRatio := datadogConfig.GetFloat64("logs_config.integrations_logs_disk_ratio")
-	maxDiskUsage, err := computeMaxDiskUsage(runPath, logsTotalUsageSetting, logsUsageRatio)
-	if err != nil {
-		ddLog.Warn("Unable to compute integrations logs max disk usage, using default value of 100 MB:", err)
+
+	var maxDiskUsage int64
+	if logsUsageRatio > 1 || logsUsageRatio < 0 {
+		ddLog.Warn("Logs usage ratio setting must be between 0 and 1, current value is:", logsUsageRatio, ". Falling back to integrations_logs_total_usage setting.")
 		maxDiskUsage = logsTotalUsageSetting
+	} else {
+		maxDiskUsage, err = computeMaxDiskUsage(runPath, logsTotalUsageSetting, logsUsageRatio)
+		if err != nil {
+			ddLog.Warn("Unable to compute integrations logs max disk usage, falling back to integrations_logs_total_usage setting:", err)
+			maxDiskUsage = logsTotalUsageSetting
+		}
 	}
 
 	return &Launcher{
@@ -109,6 +117,9 @@ func (s *Launcher) run() {
 	for {
 		select {
 		case cfg := <-s.addedConfigs:
+			if s.combinedUsageMax == 0 {
+				continue
+			}
 
 			sources, err := ad.CreateSources(cfg.Config)
 			if err != nil {
@@ -140,6 +151,10 @@ func (s *Launcher) run() {
 			}
 
 		case log := <-s.integrationsLogsChan:
+			if s.combinedUsageMax == 0 {
+				continue
+			}
+
 			s.receiveLogs(log)
 		case <-s.stop:
 			return
@@ -181,6 +196,10 @@ func (s *Launcher) receiveLogs(log integrations.IntegrationLog) {
 	// deleting files until total usage falls below the set maximum
 	for s.combinedUsageSize+logSize > s.combinedUsageMax {
 		leastRecentlyModifiedFile := s.getLeastRecentlyModifiedFile()
+		if leastRecentlyModifiedFile == nil {
+			ddLog.Warn("getLeastRecentlyModifiedFile returned nil, skipping writing log to file.")
+			return
+		}
 
 		err := s.deleteFile(leastRecentlyModifiedFile)
 		if err != nil {
@@ -212,7 +231,6 @@ func (s *Launcher) receiveLogs(log integrations.IntegrationLog) {
 	fileToUpdate.size += logSize
 }
 
-// deleteFile deletes the given file
 func (s *Launcher) deleteFile(file *fileInfo) error {
 	filename := filepath.Join(s.runPath, file.filename)
 	err := os.Remove(filename)
@@ -315,7 +333,7 @@ func (s *Launcher) integrationLogFilePath(id string) string {
 	return logFilePath
 }
 
-// computerDiskUsageMax computes the max disk space the launcher can use based
+// computeDiskUsageMax computes the max disk space the launcher can use based
 // off the integrations_logs_disk_ratio and integrations_logs_total_usage
 // settings
 func computeMaxDiskUsage(runPath string, logsTotalUsageSetting int64, usageRatio float64) (int64, error) {
@@ -327,6 +345,11 @@ func computeMaxDiskUsage(runPath string, logsTotalUsageSetting int64, usageRatio
 	diskReserved := float64(usage.Total) * (1 - usageRatio)
 	diskAvailable := int64(usage.Available) - int64(math.Ceil(diskReserved))
 
+	if diskAvailable < 0 {
+		ddLog.Warn("Available disk calculated as less than 0: ", diskAvailable, ". Disk reserved:", diskReserved)
+		diskAvailable = 0
+	}
+
 	return min(logsTotalUsageSetting, diskAvailable), nil
 }
 
@@ -363,6 +386,11 @@ func (s *Launcher) scanInitialFiles(dir string) error {
 	for s.combinedUsageSize > s.combinedUsageMax {
 		leastRecentlyModifiedFile := s.getLeastRecentlyModifiedFile()
 
+		if leastRecentlyModifiedFile == nil {
+			ddLog.Warn("getLeastRecentlyModifiedFile returned nil.")
+			return errors.New("getLeastRecentlyModifiedFile returned nil when trying to delete files")
+		}
+
 		err = s.deleteFile(leastRecentlyModifiedFile)
 		if err != nil {
 			ddLog.Warn("Error deleting log file:", err)

pkg/logs/launchers/integration/launcher_test.go

@@ -156,6 +156,14 @@ func (suite *LauncherTestSuite) TestDeleteFile() {
 	assert.True(suite.T(), os.IsNotExist(err))
 }
 
+// TestNegativeCombinedUsageMax ensures errors in combinedUsageMax don't result
+// in panics from `deleteFile`
+func (suite *LauncherTestSuite) TestNegativeCombinedUsageMax() {
+	suite.s.combinedUsageMax = -1
+	err := suite.s.scanInitialFiles(suite.s.runPath)
+	assert.NotNil(suite.T(), err)
+}
+
 // TestIntegrationLogFilePath ensures the filepath for the logs files are correct
 func (suite *LauncherTestSuite) TestIntegrationLogFilePath() {
 	id := "123456789"
@@ -458,3 +466,16 @@ func TestReadOnlyFileSystem(t *testing.T) {
 	// send a second log to make sure the launcher isn't blocking
 	integrationsComp.SendLog(logSample, id)
 }
+
+// TestCombinedDiskUsageFallback ensures the launcher falls back to the
+// logsTotalUsageSetting if there is an error in the logsUsageRatio
+func TestCombinedDiskUsageFallback(t *testing.T) {
+	totalUsage := 100
+	pkgconfigsetup.Datadog().SetWithoutSource("logs_config.integrations_logs_disk_ratio", -1)
+	pkgconfigsetup.Datadog().SetWithoutSource("logs_config.integrations_logs_total_usage", totalUsage)
+
+	integrationsComp := integrationsmock.Mock()
+	s := NewLauncher(sources.NewLogSources(), integrationsComp)
+
+	assert.Equal(t, s.combinedUsageMax, int64(totalUsage*1024*1024))
+}