Merge pull request #9 from wneessen/readability

Refactor variable names for improved code readability

cmd/server/main.go

@@ -20,49 +20,49 @@ const (
 )
 
 func main() {
-	l := slog.New(slog.NewJSONHandler(os.Stdout, nil)).With(slog.String("context", "logranger"))
-	cp := "logranger.toml"
-	cpe := os.Getenv("LOGRANGER_CONFIG")
-	if cpe != "" {
-		cp = cpe
+	logger := slog.New(slog.NewJSONHandler(os.Stdout, nil)).With(slog.String("context", "logranger"))
+	confPath := "logranger.toml"
+	confPathEnv := os.Getenv("LOGRANGER_CONFIG")
+	if confPathEnv != "" {
+		confPath = confPathEnv
 	}
 
-	p := filepath.Dir(cp)
-	f := filepath.Base(cp)
-	c, err := logranger.NewConfig(p, f)
+	path := filepath.Dir(confPath)
+	file := filepath.Base(confPath)
+	config, err := logranger.NewConfig(path, file)
 	if err != nil {
-		l.Error("failed to read/parse config", LogErrKey, err)
+		logger.Error("failed to read/parse config", LogErrKey, err)
 		os.Exit(1)
 	}
 
-	s, err := logranger.New(c)
+	server, err := logranger.New(config)
 	if err != nil {
-		l.Error("failed to create new server", LogErrKey, err)
+		logger.Error("failed to create new server", LogErrKey, err)
 		os.Exit(1)
 	}
 
 	go func() {
-		if err = s.Run(); err != nil {
-			l.Error("failed to start logranger", LogErrKey, err)
+		if err = server.Run(); err != nil {
+			logger.Error("failed to start logranger", LogErrKey, err)
 			os.Exit(1)
 		}
 	}()
 
-	sc := make(chan os.Signal, 1)
-	signal.Notify(sc)
-	for rc := range sc {
-		if rc == syscall.SIGKILL || rc == syscall.SIGABRT || rc == syscall.SIGINT || rc == syscall.SIGTERM {
-			l.Warn("received signal. shutting down server", slog.String("signal", rc.String()))
-			// s.Stop()
-			l.Info("server gracefully shut down")
+	signalChan := make(chan os.Signal, 1)
+	signal.Notify(signalChan)
+	for recvSig := range signalChan {
+		if recvSig == syscall.SIGKILL || recvSig == syscall.SIGABRT || recvSig == syscall.SIGINT || recvSig == syscall.SIGTERM {
+			logger.Warn("received signal. shutting down server", slog.String("signal", recvSig.String()))
+			// server.Stop()
+			logger.Info("server gracefully shut down")
 			os.Exit(0)
 		}
-		if rc == syscall.SIGHUP {
-			l.Info(`received signal`,
+		if recvSig == syscall.SIGHUP {
+			logger.Info(`received signal`,
 				slog.String("signal", "SIGHUP"),
 				slog.String("action", "reloading config/ruleset"))
-			if err = s.ReloadConfig(p, f); err != nil {
-				l.Error("failed to reload config", LogErrKey, err)
+			if err = server.ReloadConfig(path, file); err != nil {
+				logger.Error("failed to reload config", LogErrKey, err)
 			}
 		}
 	}

config.go

@@ -56,25 +56,25 @@ type Config struct {
 // configuration values. It takes in the file path and file name of the configuration
 // file as parameters. It returns a pointer to the Config object and an error if
 // there was a problem reading or loading the configuration.
-func NewConfig(p, f string) (*Config, error) {
-	co := Config{}
-	_, err := os.Stat(fmt.Sprintf("%s/%s", p, f))
+func NewConfig(path, file string) (*Config, error) {
+	config := Config{}
+	_, err := os.Stat(fmt.Sprintf("%s/%s", path, file))
 	if err != nil {
-		return &co, fmt.Errorf("failed to read config: %w", err)
+		return &config, fmt.Errorf("failed to read config: %w", err)
 	}
 
-	if err := fig.Load(&co, fig.Dirs(p), fig.File(f), fig.UseEnv("logranger")); err != nil {
-		return &co, fmt.Errorf("failed to load config: %w", err)
+	if err := fig.Load(&config, fig.Dirs(path), fig.File(file), fig.UseEnv("logranger")); err != nil {
+		return &config, fmt.Errorf("failed to load config: %w", err)
 	}
 
 	switch {
-	case strings.EqualFold(co.Parser.Type, "rfc3164"):
-		co.internal.ParserType = rfc3164.Type
-	case strings.EqualFold(co.Parser.Type, "rfc5424"):
-		co.internal.ParserType = rfc5424.Type
+	case strings.EqualFold(config.Parser.Type, "rfc3164"):
+		config.internal.ParserType = rfc3164.Type
+	case strings.EqualFold(config.Parser.Type, "rfc5424"):
+		config.internal.ParserType = rfc5424.Type
 	default:
-		return nil, fmt.Errorf("unknown parser type: %s", co.Parser.Type)
+		return nil, fmt.Errorf("unknown parser type: %s", config.Parser.Type)
 	}
 
-	return &co, nil
+	return &config, nil
 }

connection.go

@@ -22,14 +22,14 @@ type Connection struct {
 // NewConnection creates a new Connection object with the provided net.Conn.
 // The Connection object holds a reference to the provided net.Conn, along with an ID string,
 // bufio.Reader, and bufio.Writer. It returns a pointer to the created Connection object.
-func NewConnection(nc net.Conn) *Connection {
-	c := &Connection{
-		conn: nc,
+func NewConnection(netConn net.Conn) *Connection {
+	connection := &Connection{
+		conn: netConn,
 		id:   NewConnectionID(),
-		rb:   bufio.NewReader(nc),
-		wb:   bufio.NewWriter(nc),
+		rb:   bufio.NewReader(netConn),
+		wb:   bufio.NewWriter(netConn),
 	}
-	return c
+	return connection
 }
 
 // NewConnectionID generates a new unique message ID using a random number generator

listener.go

@@ -26,42 +26,43 @@ const (
 // NewListener initializes and returns a net.Listener based on the provided
 // configuration. It takes a pointer to a Config struct as a parameter.
 // Returns the net.Listener and an error if any occurred during initialization.
-func NewListener(c *Config) (net.Listener, error) {
-	var l net.Listener
-	var lerr error
-	switch c.Listener.Type {
+func NewListener(config *Config) (net.Listener, error) {
+	var listener net.Listener
+	var listenerErr error
+	switch config.Listener.Type {
 	case ListenerUnix:
-		rua, err := net.ResolveUnixAddr("unix", c.Listener.ListenerUnix.Path)
+		resolveUnixAddr, err := net.ResolveUnixAddr("unix", config.Listener.ListenerUnix.Path)
 		if err != nil {
 			return nil, fmt.Errorf("failed to resolve UNIX listener socket: %w", err)
 		}
-		l, lerr = net.Listen("unix", rua.String())
+		listener, listenerErr = net.Listen("unix", resolveUnixAddr.String())
 	case ListenerTCP:
-		la := net.JoinHostPort(c.Listener.ListenerTCP.Addr, fmt.Sprintf("%d", c.Listener.ListenerTCP.Port))
-		l, lerr = net.Listen("tcp", la)
+		listenAddr := net.JoinHostPort(config.Listener.ListenerTCP.Addr,
+			fmt.Sprintf("%d", config.Listener.ListenerTCP.Port))
+		listener, listenerErr = net.Listen("tcp", listenAddr)
 	case ListenerTLS:
-		if c.Listener.ListenerTLS.CertPath == "" || c.Listener.ListenerTLS.KeyPath == "" {
+		if config.Listener.ListenerTLS.CertPath == "" || config.Listener.ListenerTLS.KeyPath == "" {
 			return nil, ErrCertConfigEmpty
 		}
-		ce, err := tls.LoadX509KeyPair(c.Listener.ListenerTLS.CertPath, c.Listener.ListenerTLS.KeyPath)
+		cert, err := tls.LoadX509KeyPair(config.Listener.ListenerTLS.CertPath, config.Listener.ListenerTLS.KeyPath)
 		if err != nil {
 			return nil, fmt.Errorf("failed to load X509 certificate: %w", err)
 		}
-		la := net.JoinHostPort(c.Listener.ListenerTLS.Addr, fmt.Sprintf("%d", c.Listener.ListenerTLS.Port))
-		lc := &tls.Config{Certificates: []tls.Certificate{ce}}
-		l, lerr = tls.Listen("tcp", la, lc)
+		listenAddr := net.JoinHostPort(config.Listener.ListenerTLS.Addr, fmt.Sprintf("%d", config.Listener.ListenerTLS.Port))
+		listenConf := &tls.Config{Certificates: []tls.Certificate{cert}}
+		listener, listenerErr = tls.Listen("tcp", listenAddr, listenConf)
 	default:
 		return nil, fmt.Errorf("failed to initialize listener: unknown listener type in config")
 	}
-	if lerr != nil {
-		return nil, fmt.Errorf("failed to initialize listener: %w", lerr)
+	if listenerErr != nil {
+		return nil, fmt.Errorf("failed to initialize listener: %w", listenerErr)
 	}
-	return l, nil
+	return listener, nil
 }
 
 // UnmarshalString satisfies the fig.StringUnmarshaler interface for the ListenerType type
-func (l *ListenerType) UnmarshalString(v string) error {
-	switch strings.ToLower(v) {
+func (l *ListenerType) UnmarshalString(value string) error {
+	switch strings.ToLower(value) {
 	case "unix":
 		*l = ListenerUnix
 	case "tcp":
@@ -69,7 +70,7 @@ func (l *ListenerType) UnmarshalString(v string) error {
 	case "tls":
 		*l = ListenerTLS
 	default:
-		return fmt.Errorf("unknown listener type: %s", v)
+		return fmt.Errorf("unknown listener type: %s", value)
 	}
 	return nil
 }

plugins/actions/file/file.go

@@ -34,29 +34,29 @@ type File struct {
 //
 // If any of the required configuration parameters are missing or invalid, an error
 // is returned.
-func (f *File) Config(cm map[string]any) error {
-	if cm["file"] == nil {
+func (f *File) Config(configMap map[string]any) error {
+	if configMap["file"] == nil {
 		return nil
 	}
-	c, ok := cm["file"].(map[string]any)
+	config, ok := configMap["file"].(map[string]any)
 	if !ok {
 		return fmt.Errorf("missing configuration for file action")
 	}
 	f.Enabled = true
 
-	fp, ok := c["output_filepath"].(string)
-	if !ok || fp == "" {
+	filePath, ok := config["output_filepath"].(string)
+	if !ok || filePath == "" {
 		return fmt.Errorf("no output_filename configured for file action")
 	}
-	f.FilePath = fp
+	f.FilePath = filePath
 
-	ot, ok := c["output_template"].(string)
-	if !ok || ot == "" {
+	outputTpl, ok := config["output_template"].(string)
+	if !ok || outputTpl == "" {
 		return fmt.Errorf("not output_template configured for file action")
 	}
-	f.OutputTemplate = ot
+	f.OutputTemplate = outputTpl
 
-	if ow, ok := c["overwrite"].(bool); ok && ow {
+	if hasOverwrite, ok := config["overwrite"].(bool); ok && hasOverwrite {
 		f.Overwrite = true
 	}
 
@@ -65,34 +65,34 @@ func (f *File) Config(cm map[string]any) error {
 
 // Process satisfies the plugins.Action interface for the File type
 // It takes in the log message (lm), match groups (mg), and configuration map (cm).
-func (f *File) Process(lm parsesyslog.LogMsg, mg []string) error {
+func (f *File) Process(logMessage parsesyslog.LogMsg, matchGroup []string) error {
 	if !f.Enabled {
 		return nil
 	}
 
-	of := os.O_APPEND | os.O_CREATE | os.O_WRONLY
+	openFlags := os.O_APPEND | os.O_CREATE | os.O_WRONLY
 	if f.Overwrite {
-		of = os.O_TRUNC | os.O_CREATE | os.O_WRONLY
+		openFlags = os.O_TRUNC | os.O_CREATE | os.O_WRONLY
 	}
 
-	fh, err := os.OpenFile(f.FilePath, of, 0o600)
+	fileHandle, err := os.OpenFile(f.FilePath, openFlags, 0o600)
 	if err != nil {
 		return fmt.Errorf("failed to open file for writing in file action: %w", err)
 	}
 	defer func() {
-		_ = fh.Close()
+		_ = fileHandle.Close()
 	}()
 
-	t, err := template.Compile(lm, mg, f.OutputTemplate)
+	tpl, err := template.Compile(logMessage, matchGroup, f.OutputTemplate)
 	if err != nil {
 		return err
 	}
-	_, err = fh.WriteString(t)
+	_, err = fileHandle.WriteString(tpl)
 	if err != nil {
 		return fmt.Errorf("failed to write log message to file %q: %w",
 			f.FilePath, err)
 	}
-	if err = fh.Sync(); err != nil {
+	if err = fileHandle.Sync(); err != nil {
 		return fmt.Errorf("failed to sync memory to file %q: %w",
 			f.FilePath, err)
 	}

rule.go

@@ -32,28 +32,28 @@ type Rule struct {
 // existence, and loads the Ruleset using the fig library.
 // It checks for duplicate rules and returns an error if any duplicates are found.
 // If all operations are successful, it returns the created Ruleset and no error.
-func NewRuleset(c *Config) (*Ruleset, error) {
-	rs := &Ruleset{}
-	p := filepath.Dir(c.Server.RuleFile)
-	f := filepath.Base(c.Server.RuleFile)
-	_, err := os.Stat(fmt.Sprintf("%s/%s", p, f))
+func NewRuleset(config *Config) (*Ruleset, error) {
+	ruleset := &Ruleset{}
+	path := filepath.Dir(config.Server.RuleFile)
+	file := filepath.Base(config.Server.RuleFile)
+	_, err := os.Stat(fmt.Sprintf("%s/%s", path, file))
 	if err != nil {
-		return rs, fmt.Errorf("failed to read config: %w", err)
+		return ruleset, fmt.Errorf("failed to read config: %w", err)
 	}
 
-	if err = fig.Load(rs, fig.Dirs(p), fig.File(f), fig.UseStrict()); err != nil {
-		return rs, fmt.Errorf("failed to load ruleset: %w", err)
+	if err = fig.Load(ruleset, fig.Dirs(path), fig.File(file), fig.UseStrict()); err != nil {
+		return ruleset, fmt.Errorf("failed to load ruleset: %w", err)
 	}
 
-	rna := make([]string, 0)
-	for _, r := range rs.Rule {
-		for _, rn := range rna {
-			if strings.EqualFold(r.ID, rn) {
-				return nil, fmt.Errorf("duplicate rule found: %s", r.ID)
+	rules := make([]string, 0)
+	for _, rule := range ruleset.Rule {
+		for _, rulename := range rules {
+			if strings.EqualFold(rule.ID, rulename) {
+				return nil, fmt.Errorf("duplicate rule found: %s", rule.ID)
 			}
 		}
-		rna = append(rna, r.ID)
+		rules = append(rules, rule.ID)
 	}
 
-	return rs, nil
+	return ruleset, nil
 }

server.go

@@ -45,62 +45,62 @@ type Server struct {
 }
 
 // New creates a new instance of Server based on the provided Config
-func New(c *Config) (*Server, error) {
-	s := &Server{
-		conf: c,
+func New(config *Config) (*Server, error) {
+	server := &Server{
+		conf: config,
 	}
 
-	s.setLogLevel()
+	server.setLogLevel()
 
-	if err := s.setRules(); err != nil {
-		return s, err
+	if err := server.setRules(); err != nil {
+		return server, err
 	}
 
-	p, err := parsesyslog.New(s.conf.internal.ParserType)
+	parser, err := parsesyslog.New(server.conf.internal.ParserType)
 	if err != nil {
-		return s, fmt.Errorf("failed to initialize syslog parser: %w", err)
+		return server, fmt.Errorf("failed to initialize syslog parser: %w", err)
 	}
-	s.parser = p
+	server.parser = parser
 
 	if len(actions.Actions) <= 0 {
-		return s, fmt.Errorf("no action plugins found/configured")
+		return server, fmt.Errorf("no action plugins found/configured")
 	}
 
-	return s, nil
+	return server, nil
 }
 
 // Run starts the logranger Server by creating a new listener using the NewListener
 // method and calling RunWithListener with the obtained listener.
 func (s *Server) Run() error {
-	l, err := NewListener(s.conf)
+	listener, err := NewListener(s.conf)
 	if err != nil {
 		return err
 	}
-	return s.RunWithListener(l)
+	return s.RunWithListener(listener)
 }
 
 // RunWithListener sets the listener for the server and performs some additional
 // tasks for initializing the server. It creates a PID file, writes the process ID
 // to the file, and listens for connections. It returns an error if any of the
 // initialization steps fail.
-func (s *Server) RunWithListener(l net.Listener) error {
-	s.listener = l
+func (s *Server) RunWithListener(listener net.Listener) error {
+	s.listener = listener
 
 	// Create PID file
-	pf, err := os.Create(s.conf.Server.PIDFile)
+	pidFile, err := os.Create(s.conf.Server.PIDFile)
 	if err != nil {
 		s.log.Error("failed to create PID file", LogErrKey, err)
 		os.Exit(1)
 	}
 	pid := os.Getpid()
-	s.log.Debug("creating PID file", slog.String("pid_file", pf.Name()),
+	s.log.Debug("creating PID file", slog.String("pid_file", pidFile.Name()),
 		slog.Int("pid", pid))
-	_, err = pf.WriteString(fmt.Sprintf("%d", pid))
+	_, err = pidFile.WriteString(fmt.Sprintf("%d", pid))
 	if err != nil {
 		s.log.Error("failed to write PID to PID file", LogErrKey, err)
-		_ = pf.Close()
+		_ = pidFile.Close()
 	}
-	if err = pf.Close(); err != nil {
+	if err = pidFile.Close(); err != nil {
 		s.log.Error("failed to close PID file", LogErrKey, err)
 	}
 
@@ -116,47 +116,47 @@ func (s *Server) Listen() {
 	defer s.wg.Done()
 	s.log.Info("listening for new connections", slog.String("listen_addr", s.listener.Addr().String()))
 	for {
-		c, err := s.listener.Accept()
+		acceptConn, err := s.listener.Accept()
 		if err != nil {
 			s.log.Error("failed to accept new connection", LogErrKey, err)
 			continue
 		}
 		s.log.Debug("accepted new connection",
-			slog.String("remote_addr", c.RemoteAddr().String()))
-		conn := NewConnection(c)
+			slog.String("remote_addr", acceptConn.RemoteAddr().String()))
+		connection := NewConnection(acceptConn)
 		s.wg.Add(1)
 		go func(co *Connection) {
 			s.HandleConnection(co)
 			s.wg.Done()
-		}(conn)
+		}(connection)
 	}
 }
 
 // HandleConnection handles a single connection by parsing and processing log messages.
 // It logs debug information about the connection and measures the processing time.
 // It closes the connection when done, and logs any error encountered during the process.
-func (s *Server) HandleConnection(c *Connection) {
+func (s *Server) HandleConnection(connection *Connection) {
 	defer func() {
-		if err := c.conn.Close(); err != nil {
+		if err := connection.conn.Close(); err != nil {
 			s.log.Error("failed to close connection", LogErrKey, err)
 		}
 	}()
 
 ReadLoop:
 	for {
-		if err := c.conn.SetDeadline(time.Now().Add(s.conf.Parser.Timeout)); err != nil {
+		if err := connection.conn.SetDeadline(time.Now().Add(s.conf.Parser.Timeout)); err != nil {
 			s.log.Error("failed to set processing deadline", LogErrKey, err,
 				slog.Duration("timeout", s.conf.Parser.Timeout))
 			return
 		}
-		lm, err := s.parser.ParseReader(c.rb)
+		logMessage, err := s.parser.ParseReader(connection.rb)
 		if err != nil {
-			var ne *net.OpError
+			var netErr *net.OpError
 			switch {
-			case errors.As(err, &ne):
+			case errors.As(err, &netErr):
 				if s.conf.Log.Extended {
 					s.log.Error("network error while processing message", LogErrKey,
-						ne.Error())
+						netErr.Error())
 				}
 				return
 			case errors.Is(err, io.EOF):
@@ -172,7 +172,7 @@ ReadLoop:
 			}
 		}
 		s.wg.Add(1)
-		go s.processMessage(lm)
+		go s.processMessage(logMessage)
 	}
 }
 
@@ -182,36 +182,36 @@ ReadLoop:
 // The method first checks if the ruleset is not nil. If it is nil, no actions will be
 // executed. For each rule in the ruleset, it checks if the log message matches the
 // rule's regular expression.
-func (s *Server) processMessage(lm parsesyslog.LogMsg) {
+func (s *Server) processMessage(logMessage parsesyslog.LogMsg) {
 	defer s.wg.Done()
 	if s.ruleset != nil {
-		for _, r := range s.ruleset.Rule {
-			if !r.Regexp.MatchString(lm.Message.String()) {
+		for _, rule := range s.ruleset.Rule {
+			if !rule.Regexp.MatchString(logMessage.Message.String()) {
 				continue
 			}
-			if r.HostMatch != nil && !r.HostMatch.MatchString(lm.Hostname) {
+			if rule.HostMatch != nil && !rule.HostMatch.MatchString(logMessage.Hostname) {
 				continue
 			}
-			mg := r.Regexp.FindStringSubmatch(lm.Message.String())
-			for n, a := range actions.Actions {
-				bt := time.Now()
-				if err := a.Config(r.Actions); err != nil {
+			matchGroup := rule.Regexp.FindStringSubmatch(logMessage.Message.String())
+			for name, action := range actions.Actions {
+				startTime := time.Now()
+				if err := action.Config(rule.Actions); err != nil {
 					s.log.Error("failed to config action", LogErrKey, err,
-						slog.String("action", n), slog.String("rule_id", r.ID))
+						slog.String("action", name), slog.String("rule_id", rule.ID))
 					continue
 				}
 				s.log.Debug("log message matches rule, executing action",
-					slog.String("action", n), slog.String("rule_id", r.ID))
-				if err := a.Process(lm, mg); err != nil {
+					slog.String("action", name), slog.String("rule_id", rule.ID))
+				if err := action.Process(logMessage, matchGroup); err != nil {
 					s.log.Error("failed to process action", LogErrKey, err,
-						slog.String("action", n), slog.String("rule_id", r.ID))
+						slog.String("action", name), slog.String("rule_id", rule.ID))
 				}
 				if s.conf.Log.Extended {
-					pt := time.Since(bt)
+					procTime := time.Since(startTime)
 					s.log.Debug("action processing benchmark",
-						slog.Duration("processing_time", pt),
-						slog.String("processing_time_human", pt.String()),
-						slog.String("action", n), slog.String("rule_id", r.ID))
+						slog.Duration("processing_time", procTime),
+						slog.String("processing_time_human", procTime.String()),
+						slog.String("action", name), slog.String("rule_id", rule.ID))
 				}
 			}
 		}
@@ -226,21 +226,21 @@ func (s *Server) processMessage(lm parsesyslog.LogMsg) {
 // Finally, it creates a new `slog.Logger` with the JSON handler and sets the `s.log` field
 // of the `Server` struct to the logger, with a context value of "logranger".
 func (s *Server) setLogLevel() {
-	lo := slog.HandlerOptions{}
+	logOpts := slog.HandlerOptions{}
 	switch strings.ToLower(s.conf.Log.Level) {
 	case "debug":
-		lo.Level = slog.LevelDebug
+		logOpts.Level = slog.LevelDebug
 	case "info":
-		lo.Level = slog.LevelInfo
+		logOpts.Level = slog.LevelInfo
 	case "warn":
-		lo.Level = slog.LevelWarn
+		logOpts.Level = slog.LevelWarn
 	case "error":
-		lo.Level = slog.LevelError
+		logOpts.Level = slog.LevelError
 	default:
-		lo.Level = slog.LevelInfo
+		logOpts.Level = slog.LevelInfo
 	}
-	lh := slog.NewJSONHandler(os.Stdout, &lo)
-	s.log = slog.New(lh).With(slog.String("context", "logranger"))
+	logHandler := slog.NewJSONHandler(os.Stdout, &logOpts)
+	s.log = slog.New(logHandler).With(slog.String("context", "logranger"))
 }
 
 // setRules initializes/updates the ruleset for the logranger Server by
@@ -248,11 +248,11 @@ func (s *Server) setLogLevel() {
 // to the Server's ruleset field.
 // It returns an error if there is a failure in reading or loading the ruleset.
 func (s *Server) setRules() error {
-	rs, err := NewRuleset(s.conf)
+	ruleset, err := NewRuleset(s.conf)
 	if err != nil {
 		return fmt.Errorf("failed to read ruleset: %w", err)
 	}
-	s.ruleset = rs
+	s.ruleset = ruleset
 	return nil
 }
 
@@ -261,12 +261,12 @@ func (s *Server) setRules() error {
 // It creates a new Config using the NewConfig method and updates the Server's
 // conf field. It also reloads the configured Ruleset.
 // If an error occurs while reloading the configuration, an error is returned.
-func (s *Server) ReloadConfig(p, f string) error {
-	c, err := NewConfig(p, f)
+func (s *Server) ReloadConfig(path, file string) error {
+	config, err := NewConfig(path, file)
 	if err != nil {
 		return fmt.Errorf("failed to reload config: %w", err)
 	}
-	s.conf = c
+	s.conf = config
 
 	if err := s.setRules(); err != nil {
 		return fmt.Errorf("failed to reload ruleset: %w", err)

template/template.go

@@ -44,99 +44,99 @@ type FuncMap struct{}
 // the FuncMap. It then populates a map with values from the LogMsg
 // and current time and executes the template using the map as the
 // data source. The compiled template result or an error is returned.
-func Compile(lm parsesyslog.LogMsg, mg []string, ot string) (string, error) {
-	pt := strings.Builder{}
-	fm := NewTemplateFuncMap()
+func Compile(logMessage parsesyslog.LogMsg, matchGroup []string, outputTpl string) (string, error) {
+	procText := strings.Builder{}
+	funcMap := NewTemplateFuncMap()
 
-	ot = strings.ReplaceAll(ot, `\n`, "\n")
-	ot = strings.ReplaceAll(ot, `\t`, "\t")
-	ot = strings.ReplaceAll(ot, `\r`, "\r")
-	tpl, err := template.New("template").Funcs(fm).Parse(ot)
+	outputTpl = strings.ReplaceAll(outputTpl, `\n`, "\n")
+	outputTpl = strings.ReplaceAll(outputTpl, `\t`, "\t")
+	outputTpl = strings.ReplaceAll(outputTpl, `\r`, "\r")
+	tpl, err := template.New("template").Funcs(funcMap).Parse(outputTpl)
 	if err != nil {
-		return pt.String(), fmt.Errorf("failed to create template: %w", err)
+		return procText.String(), fmt.Errorf("failed to create template: %w", err)
 	}
 
-	dm := make(map[string]any)
-	dm["match"] = mg
-	dm["hostname"] = lm.Hostname
-	dm["timestamp"] = lm.Timestamp
-	dm["now_rfc3339"] = time.Now().Format(time.RFC3339)
-	dm["now_unix"] = time.Now().Unix()
-	dm["severity"] = lm.Severity.String()
-	dm["facility"] = lm.Facility.String()
-	dm["appname"] = lm.AppName
-	dm["original_message"] = lm.Message
+	dataMap := make(map[string]any)
+	dataMap["match"] = matchGroup
+	dataMap["hostname"] = logMessage.Hostname
+	dataMap["timestamp"] = logMessage.Timestamp
+	dataMap["now_rfc3339"] = time.Now().Format(time.RFC3339)
+	dataMap["now_unix"] = time.Now().Unix()
+	dataMap["severity"] = logMessage.Severity.String()
+	dataMap["facility"] = logMessage.Facility.String()
+	dataMap["appname"] = logMessage.AppName
+	dataMap["original_message"] = logMessage.Message
 
-	if err = tpl.Execute(&pt, dm); err != nil {
-		return pt.String(), fmt.Errorf("failed to compile template: %w", err)
+	if err = tpl.Execute(&procText, dataMap); err != nil {
+		return procText.String(), fmt.Errorf("failed to compile template: %w", err)
 	}
-	return pt.String(), nil
+	return procText.String(), nil
 }
 
 // NewTemplateFuncMap creates a new template function map by returning a
 // template.FuncMap.
 func NewTemplateFuncMap() template.FuncMap {
-	fm := FuncMap{}
+	funcMap := FuncMap{}
 	return template.FuncMap{
-		"_ToLower":  fm.ToLower,
-		"_ToUpper":  fm.ToUpper,
-		"_ToBase64": fm.ToBase64,
-		"_ToSHA1":   fm.ToSHA1,
-		"_ToSHA256": fm.ToSHA256,
-		"_ToSHA512": fm.ToSHA512,
+		"_ToLower":  funcMap.ToLower,
+		"_ToUpper":  funcMap.ToUpper,
+		"_ToBase64": funcMap.ToBase64,
+		"_ToSHA1":   funcMap.ToSHA1,
+		"_ToSHA256": funcMap.ToSHA256,
+		"_ToSHA512": funcMap.ToSHA512,
 	}
 }
 
 // ToLower returns a given string as lower-case representation
-func (*FuncMap) ToLower(s string) string {
-	return strings.ToLower(s)
+func (*FuncMap) ToLower(value string) string {
+	return strings.ToLower(value)
 }
 
 // ToUpper returns a given string as upper-case representation
-func (*FuncMap) ToUpper(s string) string {
-	return strings.ToUpper(s)
+func (*FuncMap) ToUpper(value string) string {
+	return strings.ToUpper(value)
 }
 
 // ToBase64 returns the base64 encoding of a given string.
-func (*FuncMap) ToBase64(s string) string {
-	return base64.RawStdEncoding.EncodeToString([]byte(s))
+func (*FuncMap) ToBase64(value string) string {
+	return base64.RawStdEncoding.EncodeToString([]byte(value))
 }
 
 // ToSHA1 returns the SHA-1 hash of the given string
-func (*FuncMap) ToSHA1(s string) string {
-	return toSHA(s, SHA1)
+func (*FuncMap) ToSHA1(value string) string {
+	return toSHA(value, SHA1)
 }
 
 // ToSHA256 returns the SHA-256 hash of the given string
-func (*FuncMap) ToSHA256(s string) string {
-	return toSHA(s, SHA256)
+func (*FuncMap) ToSHA256(value string) string {
+	return toSHA(value, SHA256)
 }
 
 // ToSHA512 returns the SHA-512 hash of the given string
-func (*FuncMap) ToSHA512(s string) string {
-	return toSHA(s, SHA512)
+func (*FuncMap) ToSHA512(value string) string {
+	return toSHA(value, SHA512)
 }
 
 // toSHA is a function that converts a string to a SHA hash.
 //
 // The function takes two parameters: a string 's' and a 'sa' of
 // type SHAAlgo which defines the SHA algorithm to be used.
-func toSHA(s string, sa SHAAlgo) string {
-	var h hash.Hash
-	switch sa {
+func toSHA(value string, algo SHAAlgo) string {
+	var dataHash hash.Hash
+	switch algo {
 	case SHA1:
-		h = sha1.New()
+		dataHash = sha1.New()
 	case SHA256:
-		h = sha256.New()
+		dataHash = sha256.New()
 	case SHA512:
-		h = sha512.New()
+		dataHash = sha512.New()
 	default:
 		return ""
 	}
 
-	_, err := io.WriteString(h, s)
+	_, err := io.WriteString(dataHash, value)
 	if err != nil {
 		return ""
 	}
-	return fmt.Sprintf("%x", h.Sum(nil))
+	return fmt.Sprintf("%x", dataHash.Sum(nil))
 }