refactor code for performance and security (#19)

Author: juev

.github/workflows/build.yaml

@@ -1,7 +1,10 @@
 name: check
 on:
-  push:
   pull_request:
+    branches: [main]
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+    branches: [main]
   workflow_dispatch:
 
 jobs:
@@ -15,9 +18,9 @@ jobs:
         with:
           version: latest
       -
-        uses: golangci/golangci-lint-action@v4
+        uses: golangci/golangci-lint-action@v7
         with:
-          version: latest
+          version: v2.2.0
       - 
         run: go test ./...
         shell: bash

.github/workflows/release.yml

@@ -4,25 +4,27 @@ on:
       - '*'
 
 name: "Create release"
+
+permissions:
+  contents: write
+
 jobs:
   goreleaser:
     runs-on: ubuntu-latest
     steps:
-      -
-        name: Checkout
+      - name: Checkout
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
-      - 
-        uses: kevincobain2000/action-gobrew@v2
+      - name: Set up Go
+        uses: actions/setup-go@v5
         with:
-          version: latest
-      -
-        name: Run GoReleaser
-        uses: goreleaser/goreleaser-action@v5
+          go-version: stable
+      - name: Run GoReleaser
+        uses: goreleaser/goreleaser-action@v6
         with:
           distribution: goreleaser
-          version: latest
+          version: "~> v2"
           args: release --clean
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.golangci.yaml

@@ -1,24 +1,36 @@
+version: "2"
 linters:
-  # Disable all linters.
-  # Default: false
-  disable-all: true
-  # Enable specific linter
-  # https://golangci-lint.run/usage/linters/#enabled-by-default
+  default: none
   enable:
-    - errcheck
-    - gosimple
-    - govet
-    - ineffassign
-    - staticcheck
     - dupl
+    - errcheck
     - errorlint
-    - exportloopref
     - goconst
     - gocritic
     - gocyclo
     - goprintffuncname
     - gosec
+    - govet
+    - ineffassign
     - prealloc
     - revive
-    - stylecheck
+    - staticcheck
     - whitespace
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
+formatters:
+  exclusions:
+    generated: lax
+    paths:
+      - third_party$
+      - builtin$
+      - examples$

.goreleaser.yaml

@@ -1,9 +1,11 @@
+version: 2
+
 before:
   hooks:
     - go mod tidy
+
 builds:
-  -
-    env:
+  - env:
       - CGO_ENABLED=0
     goos:
       - linux
@@ -12,6 +14,11 @@ builds:
     goarch:
       - amd64
       - arm64
+    ldflags:
+      - -s -w
+      - -X main.version={{.Version}}
+      - -X main.commit={{.Commit}}
+      - -X main.date={{.Date}}
 archives:
   -
     format: binary

cache_example.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+// Example of how to use the improved directory cache with performance monitoring
+func ExampleCacheUsage() {
+	// Create custom cache configuration
+	cacheConfig := &CacheConfig{
+		TTL:                  2 * time.Minute,  // Longer TTL for better performance
+		CleanupInterval:      1 * time.Minute,  // More frequent cleanup
+		MaxEntries:          500,               // Smaller cache for this example
+		EnablePeriodicCleanup: true,
+	}
+
+	// Create cache with custom configuration
+	fs := &DefaultFileSystem{}
+	cache := NewDirCache(cacheConfig, fs)
+	defer cache.Close() // Important: close to stop cleanup goroutine
+
+	// Test some directory checks
+	testDirs := []string{
+		"/tmp",
+		"/etc",
+		"/var",
+		"/usr/bin",
+		"/nonexistent/dir",
+	}
+
+	fmt.Println("Testing directory cache performance...")
+	
+	// First round - cache misses
+	start := time.Now()
+	for _, dir := range testDirs {
+		exists := cache.IsDirectoryNotEmpty(dir)
+		fmt.Printf("Directory %s exists and not empty: %v\n", dir, exists)
+	}
+	firstRoundTime := time.Since(start)
+
+	// Second round - cache hits (should be much faster)
+	start = time.Now()
+	for _, dir := range testDirs {
+		exists := cache.IsDirectoryNotEmpty(dir)
+		fmt.Printf("Directory %s exists and not empty: %v (cached)\n", dir, exists)
+	}
+	secondRoundTime := time.Since(start)
+
+	// Get and display cache statistics
+	stats := cache.GetStats()
+	fmt.Printf("\n=== Cache Performance Statistics ===\n")
+	fmt.Printf("Cache Hits: %d\n", stats.Hits)
+	fmt.Printf("Cache Misses: %d\n", stats.Misses)
+	fmt.Printf("Hit Ratio: %.2f%%\n", stats.HitRatio()*100)
+	fmt.Printf("Total Entries: %d\n", stats.TotalSize)
+	fmt.Printf("Evictions: %d\n", stats.Evictions)
+	
+	fmt.Printf("\n=== Performance Improvement ===\n")
+	fmt.Printf("First round (cache misses): %v\n", firstRoundTime)
+	fmt.Printf("Second round (cache hits): %v\n", secondRoundTime)
+	if secondRoundTime.Nanoseconds() > 0 {
+		speedup := float64(firstRoundTime.Nanoseconds()) / float64(secondRoundTime.Nanoseconds())
+		fmt.Printf("Speedup: %.1fx faster with cache\n", speedup)
+	}
+}
+
+// Uncomment to run the example:
+// func main() {
+// 	ExampleCacheUsage()
+// }