Created CreateSession() function and added base path in config

Author: PythonHacker24

config/app.go

@@ -1,11 +1,18 @@
 package config
 
+import (
+	"errors"
+
+	"github.com/MakeNowJust/heredoc"
+)
+
 /* app parameters */
 type App struct {
 	Name           string `yaml:"name,omitempty"`
 	Version        string `yaml:"version,omitempty"`
 	DebugMode      bool   `yaml:"debug_mode,omitempty"`
 	SessionTimeout int    `yaml:"session_timeout,omitempty"`
+	BasePath	   string `yaml:"base_path,omitempty"`		
 }
 
 /* normalization function */
@@ -27,5 +34,13 @@ func (a *App) Normalize() error {
 		a.SessionTimeout = 24
 	}
 
+	if a.BasePath == "" {
+		return errors.New(heredoc.Doc(`
+			Base path is not specified in the configuration file. 
+
+			Please check the docs for more information: 
+		`))
+	}
+
 	return nil
 }

internal/session/handler.go

@@ -0,0 +1,3 @@
+package session
+
+

internal/session/manager.go

@@ -0,0 +1,55 @@
+package session
+
+import (
+	"container/list"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/PythonHacker24/linux-acl-management-backend/config"
+)
+
+var (
+	activeSessions = make(map[string]*Session)
+	activeSessionsMutex sync.RWMutex
+)
+
+/* for creating a session for user */
+func CreateSession(username string) error {
+
+	/* lock the activeSessions mutex till the function ends */
+	activeSessionsMutex.Lock()
+	defer activeSessionsMutex.Unlock()
+
+	/* check if session exists */
+	if _, exists := activeSessions[username]; exists {
+		return fmt.Errorf("user already exists in active sessions")
+	}
+
+	/* create the session */
+	session := &Session{
+		Username: username,
+		Expiry:   time.Now().Add(time.Duration(config.BackendConfig.AppInfo.SessionTimeout) * time.Hour),
+		Timer: time.AfterFunc(time.Duration(config.BackendConfig.AppInfo.SessionTimeout) * time.Hour,
+			func() { ExpireSession(username) },
+		),
+		TransactionQueue:  list.New(),
+		CurrentWorkingDir: config.BackendConfig.AppInfo.BasePath,
+	}
+
+	/* add session to active sessions */
+	activeSessions[username] = session 
+
+	return nil
+}
+
+/* for expiring a session */
+func ExpireSession(username string) {
+	activeSessionsMutex.Lock()
+	defer activeSessionsMutex.Unlock()
+
+	/* delete if user exists in active sessions */
+	if _, exists := activeSessions[username]; exists {
+		delete(activeSessions, username)
+	}
+}