chore: enhance golangci-lint configuration and clean up error handling

- Added new linters for the examples directory to improve code quality checks.
- Updated output formatting to direct lint results to stdout for better visibility.
- Cleaned up comments related to error handling in various files for clarity and consistency.

.golangci.yml

@@ -98,8 +98,24 @@ linters:
       - path: cmd/
         linters:
           - dupl
+      
+      - path: examples/
+        linters:
+          - errcheck
+          - err113
+          - funlen
+          - gocognit
+          - gocritic
+          - gocyclo
+          - godot
+          - gosec
+          - mnd
+          - nlreturn
+          - noctx
+          - unused
+          - wrapcheck
 
 output:
   formats:
     text:
-      print-linter-name: true
+      path: stdout

client.go

@@ -286,12 +286,10 @@ func (c *Client) downloadWithBasicAuth(ctx context.Context, downloadURL string)
 	if err != nil {
 		return nil, fmt.Errorf("download request failed: %w", err)
 	}
-	//nolint:errcheck // Close error in defer is intentionally ignored
 	defer func() { _ = resp.Body.Close() }()
 
 	if resp.StatusCode != http.StatusOK {
-		//nolint:errcheck // Error response body preview - ignore read errors
+		bodyPreview, _ := io.ReadAll(resp.Body) //nolint:errcheck // Error preview - ignore read errors
-		bodyPreview, _ := io.ReadAll(resp.Body)
 		bodyStr := string(bodyPreview)
 		const maxBodyPreview = 200
 		if len(bodyStr) > maxBodyPreview {
@@ -365,12 +363,10 @@ func (c *Client) downloadWithDigestAuth(ctx context.Context, downloadURL string)
 	if err != nil {
 		return nil, fmt.Errorf("digest auth request failed: %w", err)
 	}
-	//nolint:errcheck // Close error in defer is intentionally ignored
 	defer func() { _ = resp.Body.Close() }()
 
 	if resp.StatusCode != http.StatusOK {
-		//nolint:errcheck // Error response body preview - ignore read errors
+		bodyPreview, _ := io.ReadAll(resp.Body) //nolint:errcheck // Error preview - ignore read errors
-		bodyPreview, _ := io.ReadAll(resp.Body)
 		bodyStr := string(bodyPreview)
 		const maxBodyPreview = 200
 		if len(bodyStr) > maxBodyPreview {

cmd/generate-tests/main.go

@@ -220,12 +220,10 @@ func main() {
 		log.Fatalf("Failed to create output file: %v", err)
 	}
 	defer func() {
-		//nolint:errcheck // Close error is not critical, file is already written
 		_ = f.Close()
 	}()
 
 	if err := tmpl.Execute(f, testData); err != nil {
-		//nolint:errcheck // Close error is not critical before fatal exit
 		_ = f.Close()
 		//nolint:gocritic // Fatalf exits, defer won't run - this is acceptable
 		log.Fatalf("Failed to execute template: %v", err)

cmd/onvif-cli/ascii.go

@@ -220,17 +220,17 @@ type ImageInfo struct {
 }
 
 // formatBytes converts bytes to human-readable format.
-func formatBytes(bytes int64) string {
+func formatBytes(byteCount int64) string {
-	if bytes < bufferSize1024 {
+	if byteCount < bufferSize1024 {
-		return fmt.Sprintf("%d B", bytes)
+		return fmt.Sprintf("%d B", byteCount)
 	}
 	const kbSize = 1024
 	const mbSize = 1024 * 1024
-	if bytes < mbSize {
+	if byteCount < mbSize {
-		return fmt.Sprintf("%.1f KB", float64(bytes)/kbSize)
+		return fmt.Sprintf("%.1f KB", float64(byteCount)/kbSize)
 	}
 
-	return fmt.Sprintf("%.1f MB", float64(bytes)/mbSize)
+	return fmt.Sprintf("%.1f MB", float64(byteCount)/mbSize)
 }
 
 // CreateASCIIHighQuality creates a high-quality ASCII representation.

cmd/onvif-cli/main.go

@@ -690,7 +690,6 @@ func (c *CLI) tryRTSPConnection(streamURI string) map[string]interface{} {
 	// Try to connect
 	conn, err := net.DialTimeout("tcp", hostPort, maxRetries*time.Second)
 	if err == nil {
-		//nolint:errcheck // Close error is not critical for connectivity check
 		_ = conn.Close()
 		details["reachable"] = true
 		details["port"] = strings.Split(hostPort, ":")[1]

cmd/onvif-diagnostics/main.go

@@ -1102,21 +1102,18 @@ func createTarGz(sourceDir, archivePath string) error {
 		return fmt.Errorf("failed to create archive file: %w", err)
 	}
 	defer func() {
-		//nolint:errcheck // Close error is not critical for cleanup
 		_ = archiveFile.Close()
 	}()
 
 	// Create gzip writer
 	gzWriter := gzip.NewWriter(archiveFile)
 	defer func() {
-		//nolint:errcheck // Close error is not critical for cleanup
 		_ = gzWriter.Close()
 	}()
 
 	// Create tar writer
 	tarWriter := tar.NewWriter(gzWriter)
 	defer func() {
-		//nolint:errcheck // Close error is not critical for cleanup
 		_ = tarWriter.Close()
 	}()
 
@@ -1156,7 +1153,6 @@ func createTarGz(sourceDir, archivePath string) error {
 				return fmt.Errorf("failed to open file: %w", err)
 			}
 			defer func() {
-				//nolint:errcheck // Close error is not critical for cleanup
 				_ = file.Close()
 			}()
 

discovery/discovery.go

@@ -121,7 +121,6 @@ func DiscoverWithOptions(ctx context.Context, timeout time.Duration, opts *Disco
 		return nil, fmt.Errorf("failed to listen on multicast address: %w", err)
 	}
 	defer func() {
-		//nolint:errcheck // Close error is not critical for cleanup
 		_ = conn.Close()
 	}()
 

internal/soap/soap.go

@@ -147,7 +147,6 @@ func (c *Client) Call(ctx context.Context, endpoint, action string, request, res
 		return fmt.Errorf("failed to send HTTP request: %w", err)
 	}
 	defer func() {
-		//nolint:errcheck // Close error is not critical for cleanup
 		_ = resp.Body.Close()
 	}()
 

server/soap/handler.go

@@ -55,7 +55,6 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 		return
 	}
-	//nolint:errcheck // Close error is not critical for cleanup
 	_ = r.Body.Close()
 
 	// Extract action from raw XML first (before parsing)

testing/mock_server.go

@@ -40,7 +40,6 @@ func LoadCaptureFromArchive(archivePath string) (*CameraCapture, error) {
 		return nil, fmt.Errorf("failed to open archive: %w", err)
 	}
 	defer func() {
-		//nolint:errcheck // Close error is not critical for cleanup
 		_ = file.Close()
 	}()
 
@@ -49,7 +48,6 @@ func LoadCaptureFromArchive(archivePath string) (*CameraCapture, error) {
 		return nil, fmt.Errorf("failed to create gzip reader: %w", err)
 	}
 	defer func() {
-		//nolint:errcheck // Close error is not critical for cleanup
 		_ = gzr.Close()
 	}()