various: resolve linter errors in a number of pkgs (#434)

- webui: resolve linter errors
- msghub: resolve linter errors
- policy: resolve linter errors
- extension: resolve linter errors

pkg/extension/luahost/lua.go

@@ -42,10 +42,10 @@ func New(conf config.Lua, extHost *extension.Host) (*Host, error) {
 
 	logger.Info().Msg("Loading script")
 	file, err := os.Open(scriptPath)
-	defer file.Close()
 	if err != nil {
 		return nil, err
 	}
+	defer file.Close()
 
 	return NewFromReader(logContext.Logger(), extHost, bufio.NewReader(file), scriptPath)
 }

pkg/msghub/hub.go

@@ -120,7 +120,7 @@ func (hub *Hub) AddListener(l Listener) {
 		// Playback log
 		h.history.Do(func(v interface{}) {
 			if v != nil {
-				l.Receive(v.(event.MessageMetadata))
+				_ = l.Receive(v.(event.MessageMetadata))
 			}
 		})
 

pkg/policy/address.go

@@ -228,7 +228,7 @@ func extractDomainMailbox(address string) (string, error) {
 		domain = local
 	}
 
-	if ValidateDomainPart(domain) == false {
+	if !ValidateDomainPart(domain) {
 		return "", fmt.Errorf("Domain part %q in %q failed validation", domain, address)
 	}
 

pkg/webui/sanitize/html.go

@@ -54,7 +54,9 @@ func styleTagFilter(w io.Writer, r io.Reader) error {
 		case html.StartTagToken, html.SelfClosingTagToken:
 			name, hasAttr := z.TagName()
 			if !hasAttr {
-				bw.Write(z.Raw())
+				if _, err := bw.Write(z.Raw()); err != nil {
+					return err
+				}
 				continue
 			}
 			b = append(b, '<')
@@ -81,9 +83,13 @@ func styleTagFilter(w io.Writer, r io.Reader) error {
 			if tt == html.SelfClosingTagToken {
 				b = append(b, '/')
 			}
-			bw.Write(append(b, '>'))
+			if _, err := bw.Write(append(b, '>')); err != nil {
+				return err
+			}
 		default:
-			bw.Write(z.Raw())
+			if _, err := bw.Write(z.Raw()); err != nil {
+				return err
+			}
 		}
 	}
 }