Update file watcher to only monitor directories referenced in the nginx configuration (#1134)

Author: dhurley

internal/collector/containermetricsreceiver/internal/utils.go

@@ -22,12 +22,20 @@ func ReadLines(filename string) ([]string, error) {
 }
 
 // nolint: revive
-func ReadLinesOffsetN(filename string, offset uint, n int) ([]string, error) {
+func ReadLinesOffsetN(filename string, offset uint, n int) (lines []string, err error) {
 	f, err := os.Open(filename)
+	defer func() {
+		closeErr := f.Close()
+		if closeErr != nil {
+			if err == nil {
+				err = closeErr
+			}
+		}
+	}()
+
 	if err != nil {
 		return []string{}, err
 	}
-	defer f.Close()
 
 	var ret []string
 

internal/config/types.go

@@ -415,6 +415,10 @@ func (c *Config) AreReceiversConfigured() bool {
 }
 
 func isAllowedDir(dir string, allowedDirs []string) bool {
+	if !strings.HasSuffix(dir, "/") && filepath.Ext(dir) == "" {
+		dir += "/"
+	}
+
 	for _, allowedDirectory := range allowedDirs {
 		if strings.HasPrefix(dir, allowedDirectory) {
 			return true

internal/config/types_test.go

@@ -25,10 +25,10 @@ func TestTypes_IsDirectoryAllowed(t *testing.T) {
 			allowed: true,
 			allowedDirs: []string{
 				AgentDirName,
-				"/etc/nginx",
+				"/etc/nginx/",
 				"/var/log/nginx/",
 			},
-			fileDir: "/etc/nginx/nginx.conf",
+			fileDir: "/etc/nginx",
 		},
 		{
 			name:    "Test 2: directory not allowed",

internal/datasource/config/nginx_config_parser.go

@@ -100,7 +100,7 @@ func (ncp *NginxConfigParser) Parse(ctx context.Context, instance *mpi.Instance)
 	return ncp.createNginxConfigContext(ctx, instance, payload)
 }
 
-// nolint: cyclop,revive,gocognit
+// nolint: cyclop,revive,gocognit,gocyclo
 func (ncp *NginxConfigParser) createNginxConfigContext(
 	ctx context.Context,
 	instance *mpi.Instance,
@@ -138,6 +138,10 @@ func (ncp *NginxConfigParser) createNginxConfigContext(
 		err := ncp.crossplaneConfigTraverse(ctx, &conf,
 			func(ctx context.Context, parent, directive *crossplane.Directive) error {
 				switch directive.Directive {
+				case "include":
+					include := ncp.parseIncludeDirective(directive)
+
+					nginxConfigContext.Includes = append(nginxConfigContext.Includes, include)
 				case "log_format":
 					formatMap = ncp.formatMap(directive)
 				case "access_log":
@@ -214,6 +218,17 @@ func (ncp *NginxConfigParser) createNginxConfigContext(
 	return nginxConfigContext, nil
 }
 
+func (ncp *NginxConfigParser) parseIncludeDirective(directive *crossplane.Directive) string {
+	var include string
+	if filepath.IsAbs(directive.Args[0]) {
+		include = directive.Args[0]
+	} else {
+		include = filepath.Join(filepath.Dir(directive.File), directive.Args[0])
+	}
+
+	return include
+}
+
 func (ncp *NginxConfigParser) addAccessLog(accessLog *model.AccessLog,
 	accessLogs []*model.AccessLog,
 ) []*model.AccessLog {

internal/datasource/host/info.go

@@ -205,16 +205,17 @@ func (i *Info) containerID() string {
 // mountInfo is the path: "/proc/self/mountinfo"
 func containerIDFromMountInfo(mountInfo string) (string, error) {
 	mInfoFile, err := os.Open(mountInfo)
-	if err != nil {
-		return "", fmt.Errorf("could not read %s: %w", mountInfo, err)
-	}
 	defer func(f *os.File, fileName string) {
 		closeErr := f.Close()
 		if closeErr != nil {
 			slog.Error("Unable to close file", "file", fileName, "error", closeErr)
 		}
 	}(mInfoFile, mountInfo)
 
+	if err != nil {
+		return "", fmt.Errorf("could not read %s: %w", mountInfo, err)
+	}
+
 	fileScanner := bufio.NewScanner(mInfoFile)
 	fileScanner.Split(bufio.ScanLines)
 
@@ -308,15 +309,15 @@ func (i *Info) releaseInfo(ctx context.Context, osReleaseLocation string) (relea
 
 func readOsRelease(path string) (map[string]string, error) {
 	f, err := os.Open(path)
-	if err != nil {
-		return nil, fmt.Errorf("release file %s is unreadable: %w", path, err)
-	}
 	defer func(f *os.File, fileName string) {
 		closeErr := f.Close()
 		if closeErr != nil {
 			slog.Error("Unable to close file", "file", fileName, "error", closeErr)
 		}
 	}(f, path)
+	if err != nil {
+		return nil, fmt.Errorf("release file %s is unreadable: %w", path, err)
+	}
 
 	info, err := parseOsReleaseFile(f)
 	if err != nil {

internal/file/file_manager_service.go

@@ -869,15 +869,16 @@ func (fms *FileManagerService) writeManifestFile(updatedFiles map[string]*model.
 
 	// 0600 ensures only root can read/write
 	newFile, err := os.OpenFile(fms.manifestFilePath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, filePerm)
-	if err != nil {
-		return fmt.Errorf("failed to read manifest file: %w", err)
-	}
 	defer func() {
 		if closeErr := newFile.Close(); closeErr != nil {
 			writeError = closeErr
 		}
 	}()
 
+	if err != nil {
+		return fmt.Errorf("failed to read manifest file: %w", err)
+	}
+
 	_, err = newFile.Write(manifestJSON)
 	if err != nil {
 		return fmt.Errorf("failed to write manifest file: %w", err)

internal/model/config.go

@@ -19,6 +19,7 @@ type NginxConfigContext struct {
 	AccessLogs       []*AccessLog
 	ErrorLogs        []*ErrorLog
 	NAPSysLogServers []string
+	Includes         []string
 }
 
 type APIDetails struct {