From 3102ccdfd47d4c6f747a5fc95a6d66d2dedcf34c Mon Sep 17 00:00:00 2001
From: NickIAm <nickiam@pm.me>
Date: Thu, 3 Aug 2023 21:31:27 +1000
Subject: [PATCH] fix(cli): write cachedir.tag to log directories

---
 internal/logfile/logfile.go      | 10 ++++++++++
 internal/logfile/logfile_test.go | 30 ++++++++++++++++++++++++++----
 2 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/internal/logfile/logfile.go b/internal/logfile/logfile.go
index 2589b8f779..1d605454e8 100644
--- a/internal/logfile/logfile.go
+++ b/internal/logfile/logfile.go
@@ -24,6 +24,7 @@ import (
 	"github.com/kopia/kopia/internal/zaplogutil"
 	"github.com/kopia/kopia/repo/content"
 	"github.com/kopia/kopia/repo/logging"
+	"github.com/kopia/kopia/internal/cachedir"
 )
 
 const logsDirMode = 0o700
@@ -213,6 +214,15 @@ func (c *loggingFlags) setupLogFileBasedLogger(now time.Time, subdir, suffix, lo
 		fmt.Fprintln(os.Stderr, "Unable to create logs directory:", err)
 	}
 
+	// write a cachetag.dir to the log path to keep log files out of the backup
+	cacheTagName := filepath.Join(logDir, "CACHEDIR.TAG")
+
+	if _, err := os.Stat(cacheTagName); errors.Is(err, os.ErrNotExist) {
+		if err := cachedir.WriteCacheMarker(logDir); err != nil {
+			fmt.Fprintln(os.Stderr, "Unable to write CACHETAG")
+		}
+	}
+
 	sweepLogWG := &sync.WaitGroup{}
 	doSweep := func() {}
 
diff --git a/internal/logfile/logfile_test.go b/internal/logfile/logfile_test.go
index 220a9b005d..ed5e3ca96b 100644
--- a/internal/logfile/logfile_test.go
+++ b/internal/logfile/logfile_test.go
@@ -115,8 +115,8 @@ func TestLogFileRotation(t *testing.T) {
 
 	// expected number of files per directory
 	subdirs := map[string]int{
-		"cli-logs":     3,
-		"content-logs": 4,
+		"cli-logs":     4,
+		"content-logs": 5,
 	}
 
 	for subdir, wantEntryCount := range subdirs {
@@ -189,8 +189,8 @@ func TestLogFileMaxTotalSize(t *testing.T) {
 
 			env.RunAndExpectSuccess(t, "snap", "ls", "--file-log-level=debug", "--log-dir", tmpLogDir, fmt.Sprintf("%s=%v", flag, size1MB/2))
 			size2 := getTotalDirSize(t, logSubdir)
-			require.LessOrEqual(t, size1, size0/2)
-			require.LessOrEqual(t, size2, size1/2)
+			require.LessOrEqual(t, size1, size0/2+291)
+			require.LessOrEqual(t, size2, size1/2+291)
 			require.Greater(t, size2, size1/4)
 		})
 	}
@@ -238,3 +238,25 @@ func getTotalDirSize(t *testing.T, dir string) int {
 
 	return totalSize
 }
+
+func TestCacheFileExists(t *testing.T) {
+	t.Parallel()
+
+	runner := testenv.NewInProcRunner(t)
+	runner.CustomizeApp = logfile.Attach
+
+	env := testenv.NewCLITest(t, testenv.RepoFormatNotImportant, runner)
+
+	tmpLogDir := testutil.TempDirectory(t)
+	cacheTagName := "CACHEDIR.TAG"
+
+	env.RunAndExpectSuccess(t, "repo", "create", "filesystem", "--path", env.RepoDir, "--log-dir", tmpLogDir)
+
+	if _, err := os.Stat(filepath.Join(tmpLogDir, "cli-logs", cacheTagName)); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := os.Stat(filepath.Join(tmpLogDir, "content-logs", cacheTagName)); err != nil {
+		t.Fatal(err)
+	}
+}