Implemented transaction scheduling handler

Author: PythonHacker24

internal/session/handler.go

@@ -1,3 +1,66 @@
 package session
 
-/* TODO: watchdog for session */
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"github.com/PythonHacker24/linux-acl-management-backend/internal/types"
+	"github.com/google/uuid"
+)
+
+/*
+	TODO: watchdog for session
+	Live sessions and transactions can be montired through Redis and PostgreSQL
+	the watchdog here shows the processing happening, which needs to be done in the
+	later stages of development
+*/
+
+/* frontend safe handler for issuing transaction */
+func (m *Manager) IssueTransaction(w http.ResponseWriter, r *http.Request) {
+	/* extract username from JWT Token */
+	username := r.Context().Value("username")
+
+	/* acquire manager lock to access sessions map */
+	m.mutex.Lock()
+	session := m.sessionsMap[username.(string)]
+	m.mutex.Unlock()
+
+	if session == nil {
+		http.Error(w, "Session not found", http.StatusNotFound)
+		return
+	}
+
+	/* acquire session lock for transaction operations */
+	session.Mutex.Lock()
+	defer session.Mutex.Unlock()
+
+	var req types.ScheduleTransactionRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	tx := &types.Transaction{
+		ID:         uuid.New(),
+		SessionID:  session.ID,
+		Timestamp:  time.Now(),
+		Operation:  req.Operation,
+		TargetPath: req.TargetPath,
+		Entries:    req.Entries,
+		Status:     types.StatusPending,
+		ExecutedBy: username.(string),
+	}
+
+	/* add transaction to session - session lock is already held */
+	if err := m.AddTransaction(session, tx); err != nil {
+		http.Error(w, "Failed to add transaction", http.StatusInternalServerError)
+		return
+	}
+
+	w.WriteHeader(http.StatusCreated)
+	json.NewEncoder(w).Encode(map[string]string{
+		"message": "Transaction scheduled",
+		"txn_id":  tx.ID.String(),
+	})
+}