Completed env loading and added it to main file

Author: PythonHacker24

api/middleware/middleware.go

@@ -0,0 +1 @@
+package middleware

cmd/laclm/main.go

@@ -26,18 +26,24 @@ func exec() error {
 
 	/* exec() wraps run() protecting it with user interrupts  */
 
+	/* zap.L() can be used all over the code for global level logging */
+	zap.L().Info("Logger Initiated ...")
+
 	/*
 		load config file
 		if there is an error in loading the config file, then it will exit with code 1
 	*/
 	config.LoadConfig("./config.yaml")
 
+	/*
+		load environment variables
+		if there is an error or environment variables are not set, then it will exit with code 1
+	*/
+	config.LoadEnv()
+
 	/* true for production, false for development mode */
 	utils.InitLogger(false)
 
-	/* zap.L() can be used all over the code for global level logging */
-	zap.L().Info("Logger Initiated ...")
-
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
@@ -55,6 +61,8 @@ func exec() error {
 func run(ctx context.Context) error {
 	var err error
 
+	/* complete backend system must initiate before http server starts */
+
 	/* setting up http mux and routes */
 	mux := http.NewServeMux()
 
@@ -105,5 +113,7 @@ func run(ctx context.Context) error {
 
 	zap.L().Info("HTTP server stopped")
 
+	/* after the http server is stopped, rest of the components can be shutdown */
+
 	return err
 }

config/loader.go

@@ -11,30 +11,30 @@ import (
 func LoadConfig(path string) {
 
 	/* read the yaml config file */
-	data, err := os.ReadFile(path)
-	if err != nil {
-		zap.L().Fatal("Failed to read config file",
+    data, err := os.ReadFile(path)
+    if err != nil {
+        zap.L().Fatal("Failed to read config file",
 			zap.Error(err),
 		)
-	}
+    }
 
 	/* unmarshal the yaml file to defined struct */
-	err = yaml.Unmarshal(data, &BackendConfig)
-	if err != nil {
-		zap.L().Fatal("Failed to parse YAML config",
+    err = yaml.Unmarshal(data, &BackendConfig)
+    if err != nil {
+        zap.L().Fatal("Failed to parse YAML config", 
 			zap.Error(err),
 		)
-	}
+    }
 }
 
 /* loads environment variables */
 func LoadEnv() {
 
 	/* get the JWT_SECRET_KEY from environment variable */
 	secret := os.Getenv("JWT_SECRET_KEY")
-	if secret == "" {
-		zap.L().Fatal("JWT_SECRET_KEY environment variable not set")
-	}
-
+    if secret == "" {
+        zap.L().Fatal("JWT_SECRET_KEY environment variable not set")
+    }
+	
 	EnvConfig.JWTSecret = secret
 }

internal/authentication/authentication.go

@@ -1,10 +1,13 @@
 package authentication
 
 import (
+	"fmt"
 	"time"
+	"net/http"
+	"strings"
 
-	"github.com/PythonHacker24/linux-acl-management-backend/config"
 	"github.com/golang-jwt/jwt/v5"
+	"github.com/PythonHacker24/linux-acl-management-backend/config"
 )
 
 /* generating jwt token for user identification with specified configs */
@@ -21,3 +24,59 @@ func GenerateJWT(username string) (string, error) {
 
 	return token.SignedString([]byte(config.EnvConfig.JWTSecret))
 }
+
+/* validate JWT token and return claims */
+func ValidateJWT(tokenString string) (jwt.MapClaims, error) {
+	token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
+		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+			return nil, fmt.Errorf("unexpected signing method")
+		}
+		return config.EnvConfig.JWTSecret, nil
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
+	if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
+		return claims, nil
+	}
+
+	return nil, fmt.Errorf("invalid token")
+}
+
+/* extracts username from JWT token */
+func GetUsernameFromJWT(tokenString string) (string, error) {
+
+	/* get claims from JWT Token */
+    claims, err := ValidateJWT(tokenString)
+    if err != nil {
+        return "", fmt.Errorf("invalid token: %v", err)
+    }
+
+	/* extract username from JWT Token */
+    username, ok := claims["username"].(string)
+    if !ok {
+        return "", fmt.Errorf("username not found in token")
+    }
+
+    return username, nil
+}
+
+/* extract username from http request (wrapper around GetUsernameFromJWT for http requests) */
+func ExtractUsernameFromRequest(r *http.Request) (string, error) {
+
+	/* extract authentication hearder from http request */
+    authHeader := r.Header.Get("Authorization")
+    if authHeader == "" {
+        return "", fmt.Errorf("missing Authorization header")
+    }
+	
+	/* parse the token from the header */
+    tokenParts := strings.Split(authHeader, " ")
+    if len(tokenParts) != 2 || tokenParts[0] != "Bearer" {
+        return "", fmt.Errorf("invalid Authorization header format")
+    }
+
+    return GetUsernameFromJWT(tokenParts[1])
+}

internal/models/models.go

@@ -36,9 +36,9 @@ type Logging struct {
 
 /* file system server parameters */
 type FileSystemServers struct {
+	Remote *Remote `yaml:"remote"`
 	Path   string  `yaml:"path"`
 	Method string  `yaml:"method"`
-	Remote *Remote `yaml:"remote"`
 }
 
 /* remote parameters for file system server with laclm daemons installed */

internal/utils/utils.go

@@ -8,8 +8,6 @@ import (
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 	"gopkg.in/natefinch/lumberjack.v2"
-
-	"github.com/PythonHacker24/linux-acl-management-backend/internal/models"
 )
 
 var (