Standardize logging

go.mod

@@ -2,18 +2,21 @@ module github.com/fosrl/gerbil
 
 go 1.21.5
 
+require (
+	github.com/vishvananda/netlink v1.3.0
+	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230429144221-925a1e7659e6
+)
+
 require (
 	github.com/google/go-cmp v0.5.9 // indirect
 	github.com/josharian/native v1.1.0 // indirect
 	github.com/mdlayher/genetlink v1.3.2 // indirect
 	github.com/mdlayher/netlink v1.7.2 // indirect
 	github.com/mdlayher/socket v0.4.1 // indirect
-	github.com/vishvananda/netlink v1.3.0 // indirect
 	github.com/vishvananda/netns v0.0.4 // indirect
 	golang.org/x/crypto v0.8.0 // indirect
 	golang.org/x/net v0.9.0 // indirect
 	golang.org/x/sync v0.1.0 // indirect
 	golang.org/x/sys v0.10.0 // indirect
 	golang.zx2c4.com/wireguard v0.0.0-20230325221338-052af4a8072b // indirect
-	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230429144221-925a1e7659e6 // indirect
 )

logger/level.go

@@ -0,0 +1,27 @@
+package logger
+
+type LogLevel int
+
+const (
+	DEBUG LogLevel = iota
+	INFO
+	WARN
+	ERROR
+	FATAL
+)
+
+var levelStrings = map[LogLevel]string{
+	DEBUG: "DEBUG",
+	INFO:  "INFO",
+	WARN:  "WARN",
+	ERROR: "ERROR",
+	FATAL: "FATAL",
+}
+
+// String returns the string representation of the log level
+func (l LogLevel) String() string {
+	if s, ok := levelStrings[l]; ok {
+		return s
+	}
+	return "UNKNOWN"
+}

logger/logger.go

@@ -0,0 +1,106 @@
+package logger
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"sync"
+	"time"
+)
+
+// Logger struct holds the logger instance
+type Logger struct {
+	logger *log.Logger
+	level  LogLevel
+}
+
+var (
+	defaultLogger *Logger
+	once          sync.Once
+)
+
+// NewLogger creates a new logger instance
+func NewLogger() *Logger {
+	return &Logger{
+		logger: log.New(os.Stdout, "", 0),
+		level:  DEBUG,
+	}
+}
+
+// Init initializes the default logger
+func Init() *Logger {
+	once.Do(func() {
+		defaultLogger = NewLogger()
+	})
+	return defaultLogger
+}
+
+// GetLogger returns the default logger instance
+func GetLogger() *Logger {
+	if defaultLogger == nil {
+		Init()
+	}
+	return defaultLogger
+}
+
+// SetLevel sets the minimum logging level
+func (l *Logger) SetLevel(level LogLevel) {
+	l.level = level
+}
+
+// log handles the actual logging
+func (l *Logger) log(level LogLevel, format string, args ...interface{}) {
+	if level < l.level {
+		return
+	}
+	timestamp := time.Now().Format("2006/01/02 15:04:05")
+	message := fmt.Sprintf(format, args...)
+	l.logger.Printf("%s: %s %s", level.String(), timestamp, message)
+}
+
+// Debug logs debug level messages
+func (l *Logger) Debug(format string, args ...interface{}) {
+	l.log(DEBUG, format, args...)
+}
+
+// Info logs info level messages
+func (l *Logger) Info(format string, args ...interface{}) {
+	l.log(INFO, format, args...)
+}
+
+// Warn logs warning level messages
+func (l *Logger) Warn(format string, args ...interface{}) {
+	l.log(WARN, format, args...)
+}
+
+// Error logs error level messages
+func (l *Logger) Error(format string, args ...interface{}) {
+	l.log(ERROR, format, args...)
+}
+
+// Fatal logs fatal level messages and exits
+func (l *Logger) Fatal(format string, args ...interface{}) {
+	l.log(FATAL, format, args...)
+	os.Exit(1)
+}
+
+// Global helper functions
+func Debug(format string, args ...interface{}) {
+	GetLogger().Debug(format, args...)
+}
+
+func Info(format string, args ...interface{}) {
+	GetLogger().Info(format, args...)
+}
+
+func Warn(format string, args ...interface{}) {
+	GetLogger().Warn(format, args...)
+}
+
+func Error(format string, args ...interface{}) {
+	GetLogger().Error(format, args...)
+}
+
+func Fatal(format string, args ...interface{}) {
+	GetLogger().Fatal(format, args...)
+}

main.go

@@ -6,13 +6,14 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"log"
 	"net"
 	"net/http"
 	"os"
+	"strings"
 	"sync"
 	"time"
 
+	"github.com/fosrl/gerbil/logger"
 	"github.com/vishvananda/netlink"
 	"golang.zx2c4.com/wireguard/wgctrl"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
@@ -53,6 +54,23 @@ var (
 	wgClient *wgctrl.Client
 )
 
+func parseLogLevel(level string) logger.LogLevel {
+	switch strings.ToUpper(level) {
+	case "DEBUG":
+		return logger.DEBUG
+	case "INFO":
+		return logger.INFO
+	case "WARN":
+		return logger.WARN
+	case "ERROR":
+		return logger.ERROR
+	case "FATAL":
+		return logger.FATAL
+	default:
+		return logger.INFO // default to INFO if invalid level provided
+	}
+}
+
 func main() {
 	var err error
 	var wgconfig WgConfig
@@ -65,8 +83,13 @@ func main() {
 	reportBandwidthTo := flag.String("reportBandwidthTo", "", "Address to listen on")
 	generateAndSaveKeyTo := flag.String("generateAndSaveKeyTo", "", "Path to save generated private key")
 	reachableAt := flag.String("reachableAt", "", "Endpoint of the http server to tell remote config about")
+	logLevel := flag.String("log-level", "INFO", "Log level (DEBUG, INFO, WARN, ERROR, FATAL)")
+
 	flag.Parse()
 
+	logger.Init()
+	logger.GetLogger().SetLevel(parseLogLevel(*logLevel))
+
 	if *interfaceNameArg != "" {
 		interfaceName = *interfaceNameArg
 	}
@@ -76,7 +99,7 @@ func main() {
 
 	// Validate that only one config option is provided
 	if (*configFile != "" && *remoteConfigURL != "") || (*configFile == "" && *remoteConfigURL == "") {
-		log.Fatal("Please provide either --config or --remoteConfig, but not both")
+		logger.Fatal("Please provide either --config or --remoteConfig, but not both")
 	}
 
 	var key wgtypes.Key
@@ -86,21 +109,21 @@ func main() {
 			// generate a new private key
 			key, err = wgtypes.GeneratePrivateKey()
 			if err != nil {
-				log.Fatalf("Failed to generate private key: %v", err)
+				logger.Fatal("Failed to generate private key: %v", err)
 			}
 			// save the key to the file
 			err = os.WriteFile(*generateAndSaveKeyTo, []byte(key.String()), 0644)
 			if err != nil {
-				log.Fatalf("Failed to save private key: %v", err)
+				logger.Fatal("Failed to save private key: %v", err)
 			}
 		} else {
 			keyData, err := os.ReadFile(*generateAndSaveKeyTo)
 			if err != nil {
-				log.Fatalf("Failed to read private key: %v", err)
+				logger.Fatal("Failed to read private key: %v", err)
 			}
 			key, err = wgtypes.ParseKey(string(keyData))
 			if err != nil {
-				log.Fatalf("Failed to parse private key: %v", err)
+				logger.Fatal("Failed to parse private key: %v", err)
 			}
 		}
 	} else {
@@ -109,7 +132,7 @@ func main() {
 			// generate a new one
 			key, err = wgtypes.GeneratePrivateKey()
 			if err != nil {
-				log.Fatalf("Failed to generate private key: %v", err)
+				logger.Fatal("Failed to generate private key: %v", err)
 			}
 		}
 	}
@@ -118,7 +141,7 @@ func main() {
 	if *configFile != "" {
 		wgconfig, err = loadConfig(*configFile)
 		if err != nil {
-			log.Fatalf("Failed to load configuration: %v", err)
+			logger.Fatal("Failed to load configuration: %v", err)
 		}
 		if wgconfig.PrivateKey == "" {
 			wgconfig.PrivateKey = key.String()
@@ -126,20 +149,20 @@ func main() {
 	} else {
 		wgconfig, err = loadRemoteConfig(*remoteConfigURL, key, *reachableAt)
 		if err != nil {
-			log.Fatalf("Failed to load configuration: %v", err)
+			logger.Fatal("Failed to load configuration: %v", err)
 		}
 		wgconfig.PrivateKey = key.String()
 	}
 
 	wgClient, err = wgctrl.New()
 	if err != nil {
-		log.Fatalf("Failed to create WireGuard client: %v", err)
+		logger.Fatal("Failed to create WireGuard client: %v", err)
 	}
 	defer wgClient.Close()
 
 	// Ensure the WireGuard interface exists and is configured
 	if err := ensureWireguardInterface(wgconfig); err != nil {
-		log.Fatalf("Failed to ensure WireGuard interface: %v", err)
+		logger.Fatal("Failed to ensure WireGuard interface: %v", err)
 	}
 
 	// Ensure the WireGuard peers exist
@@ -150,8 +173,8 @@ func main() {
 	}
 
 	http.HandleFunc("/peer", handlePeer)
-	log.Printf("Starting server on %s", listenAddr)
-	log.Fatal(http.ListenAndServe(listenAddr, nil))
+	logger.Info("Starting server on %s", listenAddr)
+	logger.Fatal("Failed to start server: %v", http.ListenAndServe(listenAddr, nil))
 }
 
 func loadRemoteConfig(url string, key wgtypes.Key, reachableAt string) (WgConfig, error) {
@@ -164,7 +187,7 @@ func loadRemoteConfig(url string, key wgtypes.Key, reachableAt string) (WgConfig
 	resp, err := http.Post(url, "application/json", body)
 	if err != nil {
 		// print the error
-		fmt.Println("Error fetching remote config:", err)
+		logger.Error("Error fetching remote config %s: %v", url, err)
 		return WgConfig{}, err
 	}
 	defer resp.Body.Close()
@@ -184,7 +207,7 @@ func loadConfig(filename string) (WgConfig, error) {
 	// Open the JSON file
 	file, err := os.Open(filename)
 	if err != nil {
-		fmt.Println("Error opening file:", err)
+		logger.Error("Error opening file %s: %v", filename, err)
 		return WgConfig{}, err
 	}
 	defer file.Close()
@@ -192,7 +215,7 @@ func loadConfig(filename string) (WgConfig, error) {
 	// Read the file contents
 	byteValue, err := io.ReadAll(file)
 	if err != nil {
-		fmt.Println("Error reading file:", err)
+		logger.Error("Error reading file %s: %v", filename, err)
 		return WgConfig{}, err
 	}
 
@@ -202,7 +225,7 @@ func loadConfig(filename string) (WgConfig, error) {
 	// Unmarshal the JSON data into the struct
 	err = json.Unmarshal(byteValue, &wgconfig)
 	if err != nil {
-		fmt.Println("Error unmarshaling JSON:", err)
+		logger.Error("Error unmarshaling JSON data: %v", err)
 		return WgConfig{}, err
 	}
 
@@ -217,23 +240,23 @@ func ensureWireguardInterface(wgconfig WgConfig) error {
 			// Interface doesn't exist, so create it
 			err = createWireGuardInterface()
 			if err != nil {
-				log.Fatalf("Failed to create WireGuard interface: %v", err)
+				logger.Fatal("Failed to create WireGuard interface: %v", err)
 			}
-			log.Printf("Created WireGuard interface %s\n", interfaceName)
+			logger.Info("Created WireGuard interface %s\n", interfaceName)
 		} else {
-			log.Fatalf("Error checking for WireGuard interface: %v", err)
+			logger.Fatal("Error checking for WireGuard interface: %v", err)
 		}
 	} else {
-		log.Printf("WireGuard interface %s already exists\n", interfaceName)
+		logger.Info("WireGuard interface %s already exists\n", interfaceName)
 		return nil
 	}
 
 	// Assign IP address to the interface
 	err = assignIPAddress(wgconfig.IpAddress)
 	if err != nil {
-		log.Fatalf("Failed to assign IP address: %v", err)
+		logger.Fatal("Failed to assign IP address: %v", err)
 	}
-	log.Printf("Assigned IP address %s to interface %s\n", wgconfig.IpAddress, interfaceName)
+	logger.Info("Assigned IP address %s to interface %s\n", wgconfig.IpAddress, interfaceName)
 
 	// Check if the interface already exists
 	_, err = wgClient.Device(interfaceName)
@@ -269,7 +292,7 @@ func ensureWireguardInterface(wgconfig WgConfig) error {
 		return fmt.Errorf("failed to bring up interface: %v", err)
 	}
 
-	log.Printf("WireGuard interface %s created and configured", interfaceName)
+	logger.Info("WireGuard interface %s created and configured", interfaceName)
 
 	return nil
 }
@@ -403,7 +426,7 @@ func addPeer(peer Peer) error {
 		return fmt.Errorf("failed to add peer: %v", err)
 	}
 
-	log.Printf("Peer %s added successfully", peer.PublicKey)
+	logger.Info("Peer %s added successfully", peer.PublicKey)
 
 	return nil
 }
@@ -444,7 +467,7 @@ func removePeer(publicKey string) error {
 		return fmt.Errorf("failed to remove peer: %v", err)
 	}
 
-	log.Printf("Peer %s removed successfully", publicKey)
+	logger.Info("Peer %s removed successfully", publicKey)
 
 	return nil
 }
@@ -455,7 +478,7 @@ func periodicBandwidthCheck(endpoint string) {
 
 	for range ticker.C {
 		if err := reportPeerBandwidth(endpoint); err != nil {
-			log.Printf("Failed to report peer bandwidth: %v", err)
+			logger.Info("Failed to report peer bandwidth: %v", err)
 		}
 	}
 }
@@ -546,6 +569,5 @@ func reportPeerBandwidth(apiURL string) error {
 		return fmt.Errorf("API returned non-OK status: %s", resp.Status)
 	}
 
-	// log.Println("Bandwidth data sent successfully")
 	return nil
 }