add --keep-dist

cmd/dkl-dir2config/render-context_test.go

@@ -33,7 +33,7 @@ m:
   c1: s
 ` {
 		t.Errorf("got\n%s", v)
-}
+	}
 }
 
 func parse(s string) (r interface{}) {

cmd/dkl-local-server/cache.go

@@ -86,7 +86,12 @@ func updateCache() {
 
 	existing := []string{}
 
-	for _, dir := range []string{distDir, cacheDir} {
+	cleanDirs := []string{cacheDir}
+	if !*keepDist {
+		cleanDirs = append(cleanDirs, distDir)
+	}
+
+	for _, dir := range cleanDirs {
 		fs.WalkDir(os.DirFS(dir), ".", func(path string, d fs.DirEntry, err error) error {
 			if err != nil {
 				log.Printf("update cache: walking %s failed: %v", dir, err)

cmd/dkl-local-server/data.go

@@ -9,6 +9,7 @@ import (
 
 var (
 	dataDir  = flag.String("data", "/var/lib/direktil", "Data dir")
+	keepDist = flag.Bool("keep-dist", false, "Keep dist files during cache cleanup (still removes assembled erofs)")
 )
 
 func configFilePath() string {