Add logging tests

util/log_test.go

@@ -0,0 +1,96 @@
+package util
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/require"
+)
+
+// TestSetupLogFile_RotatesOnSize drives >MaxSize bytes through the writer
+// returned by setupLogFile and asserts a backup file appears.
+func TestSetupLogFile_RotatesOnSize(t *testing.T) {
+	t.Setenv("NB_LOG_MAX_SIZE_MB", "1")
+
+	dir := t.TempDir()
+	logPath := filepath.Join(dir, "netbird.log")
+
+	w, err := setupLogFile(logPath, false)
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		if c, ok := w.(io.Closer); ok {
+			_ = c.Close()
+		}
+	})
+
+	chunk := []byte(strings.Repeat("x", 64*1024) + "\n")
+	for range 20 {
+		_, err := w.Write(chunk)
+		require.NoError(t, err)
+	}
+
+	info, err := os.Stat(logPath)
+	require.NoError(t, err)
+	require.Less(t, info.Size(), int64(1<<20),
+		"active log should be < 1 MB after rotation, got %d", info.Size())
+
+	require.Eventually(t, func() bool {
+		entries, _ := os.ReadDir(dir)
+		for _, e := range entries {
+			name := e.Name()
+			if name == filepath.Base(logPath) {
+				continue
+			}
+			if strings.HasPrefix(name, "netbird-") && strings.HasSuffix(name, ".log.gz") {
+				return true
+			}
+		}
+		return false
+	}, 5*time.Second, 50*time.Millisecond, "expected a rotated backup file in %s", dir)
+}
+
+// TestSetupLogFile_RotationDisabled verifies that with rotation off, the file
+// grows past MaxSize and no backups are created.
+func TestSetupLogFile_RotationDisabled(t *testing.T) {
+	t.Setenv("NB_LOG_MAX_SIZE_MB", "1")
+
+	dir := t.TempDir()
+	logPath := filepath.Join(dir, "netbird.log")
+
+	w, err := setupLogFile(logPath, true)
+	require.NoError(t, err)
+
+	f, ok := w.(*os.File)
+	require.True(t, ok, "expected plain *os.File when rotation is disabled, got %T", w)
+	t.Cleanup(func() { _ = f.Close() })
+
+	chunk := []byte(strings.Repeat("y", 64*1024) + "\n")
+	for range 20 {
+		_, err := w.Write(chunk)
+		require.NoError(t, err)
+	}
+
+	info, err := os.Stat(logPath)
+	require.NoError(t, err)
+	require.GreaterOrEqual(t, info.Size(), int64(1<<20),
+		"file should exceed MaxSize when rotation is disabled, got %d", info.Size())
+
+	entries, err := os.ReadDir(dir)
+	require.NoError(t, err)
+	require.Len(t, entries, 1, "no backup files should exist when rotation is disabled, got %v", entries)
+}
+
+// TestIsRotationDisabled_EnvFlag covers the NB_LOG_DISABLE_ROTATION env path.
+// The logrotate-conflict branch is exercised separately on linux.
+func TestIsRotationDisabled_EnvFlag(t *testing.T) {
+	logger := log.New()
+	logger.SetOutput(io.Discard)
+
+	t.Setenv("NB_LOG_DISABLE_ROTATION", "true")
+	require.True(t, isRotationDisabled(logger))
+}

util/logrotate_linux.go

@@ -23,7 +23,11 @@ const (
 // indications of conflict with netbird. It returns true and the config file
 // path if a conflict was found.
 func FindFirstLogrotateConflict() (bool, string) {
-	for _, f := range listLogrotateConfigs() {
+	return findFirstLogrotateConflictIn(defaultLogrotateConfPath, defaultLogrotateConfDir)
+}
+
+func findFirstLogrotateConflictIn(confPath, confDir string) (bool, string) {
+	for _, f := range listLogrotateConfigs(confPath, confDir) {
 		present, err := scanLogrotateFile(f, netbirdString)
 		if err != nil {
 			if !errors.Is(err, fs.ErrNotExist) {
@@ -39,9 +43,9 @@ func FindFirstLogrotateConflict() (bool, string) {
 }
 
 // listLogrotateConfigs returns all config files for logrotate.
-func listLogrotateConfigs() []string {
-	files := []string{defaultLogrotateConfPath}
-	entries, err := os.ReadDir(defaultLogrotateConfDir)
+func listLogrotateConfigs(confPath, confDir string) []string {
+	files := []string{confPath}
+	entries, err := os.ReadDir(confDir)
 	if err != nil {
 		return files
 	}
@@ -49,7 +53,7 @@ func listLogrotateConfigs() []string {
 		if e.IsDir() {
 			continue
 		}
-		files = append(files, filepath.Join(defaultLogrotateConfDir, e.Name()))
+		files = append(files, filepath.Join(confDir, e.Name()))
 	}
 	return files
 }

util/logrotate_linux_test.go

@@ -0,0 +1,95 @@
+//go:build linux
+
+package util
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestFindFirstLogrotateConflict(t *testing.T) {
+	t.Run("conflict in confDir", func(t *testing.T) {
+		confPath, confDir := newLogrotateLayout(t)
+		conflictPath := filepath.Join(confDir, "netbird")
+		writeLogrotateConfig(t, conflictPath, `/var/log/netbird/*.log {
+    daily
+    rotate 7
+}`)
+		writeLogrotateConfig(t, filepath.Join(confDir, "nginx"), `/var/log/nginx/*.log { daily }`)
+
+		got, path := findFirstLogrotateConflictIn(confPath, confDir)
+		require.True(t, got)
+		require.Equal(t, conflictPath, path)
+	})
+
+	t.Run("conflict in main conf file", func(t *testing.T) {
+		confPath, confDir := newLogrotateLayout(t)
+		writeLogrotateConfig(t, confPath, `weekly
+rotate 4
+include /etc/logrotate.d
+/var/log/netbird/client.log { rotate 5 }`)
+
+		got, path := findFirstLogrotateConflictIn(confPath, confDir)
+		require.True(t, got)
+		require.Equal(t, confPath, path)
+	})
+
+	t.Run("no conflict when netbird is absent", func(t *testing.T) {
+		confPath, confDir := newLogrotateLayout(t)
+		writeLogrotateConfig(t, filepath.Join(confDir, "nginx"), `/var/log/nginx/*.log { daily }`)
+		writeLogrotateConfig(t, filepath.Join(confDir, "syslog"), `/var/log/syslog { weekly }`)
+
+		got, path := findFirstLogrotateConflictIn(confPath, confDir)
+		require.False(t, got)
+		require.Empty(t, path)
+	})
+
+	t.Run("commented-out netbird line is ignored", func(t *testing.T) {
+		confPath, confDir := newLogrotateLayout(t)
+		writeLogrotateConfig(t, filepath.Join(confDir, "misc"), `# /var/log/netbird/*.log { daily }
+/var/log/other.log { weekly }`)
+
+		got, path := findFirstLogrotateConflictIn(confPath, confDir)
+		require.False(t, got)
+		require.Empty(t, path)
+	})
+
+	t.Run("subdirectories in confDir are ignored", func(t *testing.T) {
+		confPath, confDir := newLogrotateLayout(t)
+		sub := filepath.Join(confDir, "nested")
+		require.NoError(t, os.MkdirAll(sub, 0o755))
+		writeLogrotateConfig(t, filepath.Join(sub, "netbird"), `/var/log/netbird/*.log { daily }`)
+
+		got, path := findFirstLogrotateConflictIn(confPath, confDir)
+		require.False(t, got)
+		require.Empty(t, path)
+	})
+
+	t.Run("missing paths return no conflict", func(t *testing.T) {
+		dir := t.TempDir()
+		got, path := findFirstLogrotateConflictIn(
+			filepath.Join(dir, "does-not-exist.conf"),
+			filepath.Join(dir, "does-not-exist.d"),
+		)
+		require.False(t, got)
+		require.Empty(t, path)
+	})
+}
+
+// newLogrotateLayout creates a temp logrotate.conf path and logrotate.d dir,
+// returning their paths. The conf file itself is not created.
+func newLogrotateLayout(t *testing.T) (confPath, confDir string) {
+	t.Helper()
+	root := t.TempDir()
+	confDir = filepath.Join(root, "logrotate.d")
+	require.NoError(t, os.MkdirAll(confDir, 0o755))
+	return filepath.Join(root, "logrotate.conf"), confDir
+}
+
+func writeLogrotateConfig(t *testing.T, path, body string) {
+	t.Helper()
+	require.NoError(t, os.WriteFile(path, []byte(body), 0o644))
+}