fix: resolve golangci-lint warnings and update GitHub Actions

- add http.MaxBytesReader (64MB cap) to form handlers (gosec G120)
- replace sort with slices.Sort/SortFunc (revive)
- use min() builtin instead of if/else (modernize)
- extract setupLog helper with secret masking
- add modernize linter to golangci config
- bump docker/setup-qemu-action and setup-buildx-action to v4

Author: umputun

.github/workflows/ci.yml

@@ -50,11 +50,11 @@ jobs:
           COVERALLS_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
       - name: set up QEMU
-        uses: docker/setup-qemu-action@v3
+        uses: docker/setup-qemu-action@v4
 
       - name: set up Docker Buildx
         id: buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: available platforms
         run: echo ${{ steps.buildx.outputs.platforms }}

backend/.golangci.yml

@@ -30,6 +30,7 @@ linters:
     - unparam
     - unused
     - whitespace
+    - modernize
   settings:
     goconst:
       min-len: 2
@@ -80,4 +81,4 @@ formatters:
     paths:
       - third_party$
       - builtin$
-      - examples$
+      - examples$

backend/extractor/pics.go

@@ -1,9 +1,10 @@
 package extractor
 
 import (
+	"cmp"
 	"io"
 	"net/http"
-	"sort"
+	"slices"
 	"sync"
 	"time"
 
@@ -39,7 +40,7 @@ func (f *UReadability) extractPics(iselect *goquery.Selection, url string) (main
 		images[r.size] = r.url
 		allImages = append(allImages, r.url)
 	}
-	sort.Strings(allImages)
+	slices.Sort(allImages)
 	if len(images) == 0 {
 		return "", nil, false
 	}
@@ -49,7 +50,7 @@ func (f *UReadability) extractPics(iselect *goquery.Selection, url string) (main
 	for k := range images {
 		keys = append(keys, k)
 	}
-	sort.Sort(sort.Reverse(sort.IntSlice(keys)))
+	slices.SortFunc(keys, func(a, b int) int { return cmp.Compare(b, a) })
 	mainImage = images[keys[0]]
 	log.Printf("[DEBUG] total images from %s = %d, main=%s (%d)", url, len(images), mainImage, keys[0])
 	return mainImage, allImages, true

backend/extractor/text.go

@@ -41,10 +41,7 @@ func (f *UReadability) getText(content, title string) string {
 // get snippet from clean text content
 func (f *UReadability) getSnippet(cleanText string) string {
 	cleanText = strings.ReplaceAll(cleanText, "\n", " ")
-	size := len([]rune(cleanText))
-	if size > f.SnippetSize {
-		size = f.SnippetSize
-	}
+	size := min(len([]rune(cleanText)), f.SnippetSize)
 	snippet := []rune(cleanText)[:size]
 	// go back in snippet and found first space
 	for i := len(snippet) - 1; i >= 0; i-- {

backend/main.go

@@ -34,12 +34,7 @@ func main() {
 	if _, err := flags.Parse(&opts); err != nil {
 		os.Exit(1)
 	}
-	var options []log.Option
-	if opts.Debug {
-		options = []log.Option{log.Debug, log.CallerFile}
-	}
-	options = append(options, log.Msec, log.LevelBraces)
-	log.Setup(options...)
+	setupLog(opts.Debug, opts.MongoURI, opts.Token)
 
 	log.Printf("[INFO] started ukeeper-readability service %s", revision)
 	db, err := datastore.New(opts.MongoURI, opts.MongoDB, opts.MongoDelay)
@@ -69,3 +64,12 @@ func main() {
 
 	srv.Run(ctx, opts.Address, opts.Port, opts.FrontendDir)
 }
+
+func setupLog(dbg bool, secrets ...string) { //nolint:revive // control flag is fine for init helper
+	log.Secret(secrets...)
+	if dbg {
+		log.Setup(log.Debug, log.CallerFile, log.Msec, log.LevelBraces)
+		return
+	}
+	log.Setup(log.Msec, log.LevelBraces)
+}

backend/rest/server.go

@@ -204,8 +204,8 @@ func (s *Server) extractArticleEmulateReadability(w http.ResponseWriter, r *http
 
 // generates previews for the provided test URLs
 func (s *Server) handlePreview(w http.ResponseWriter, r *http.Request) {
-	err := r.ParseForm()
-	if err != nil {
+	r.Body = http.MaxBytesReader(w, r.Body, 64<<20) // limit to 64MB
+	if err := r.ParseForm(); err != nil {
 		http.Error(w, "Failed to parse form", http.StatusBadRequest)
 		return
 	}
@@ -268,17 +268,16 @@ func (s *Server) handlePreview(w http.ResponseWriter, r *http.Request) {
 		Results: results,
 	}
 
-	err = s.rulePage.ExecuteTemplate(w, "preview.gohtml", data)
-	if err != nil {
+	if err := s.rulePage.ExecuteTemplate(w, "preview.gohtml", data); err != nil {
 		http.Error(w, err.Error(), http.StatusInternalServerError)
 		return
 	}
 }
 
 // saveRule upsert rule, forcing enabled=true
 func (s *Server) saveRule(w http.ResponseWriter, r *http.Request) {
-	err := r.ParseForm()
-	if err != nil {
+	r.Body = http.MaxBytesReader(w, r.Body, 64<<20) // limit to 64MB
+	if err := r.ParseForm(); err != nil {
 		http.Error(w, "Failed to parse form", http.StatusBadRequest)
 		return
 	}