Added local transaction execution for BeeGFS like systems

Author: PythonHacker24

internal/transprocessor/localtxn.go

@@ -0,0 +1,104 @@
+package transprocessor
+
+import (
+	"fmt"
+	"os/exec"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/PythonHacker24/linux-acl-management-backend/internal/types"
+	"go.uber.org/zap"
+)
+
+/* maintains locks on file which are actively under ACL modifications */
+var pathLocks sync.Map
+
+/* locks a given file path */
+func getPathLock(path string) *sync.Mutex {
+	mtx, _ := pathLocks.LoadOrStore(path, &sync.Mutex{})
+	return mtx.(*sync.Mutex)
+}
+
+/* handles local transaction execution (change permissions via mounts) */
+func (p *PermProcessor) HandleLocalTransaction(txn *types.Transaction, absolutePath string) error {
+	aclEntry := BuildACLEntry(txn.Entries)
+
+	/* REMOVE THIS */
+	zap.L().Info("ACL Request recieved",
+		zap.String("Transaction ID", txn.ID.String()),
+		zap.String("Action", txn.Entries.Action),
+		zap.String("Entry", aclEntry),
+		zap.String("Path", txn.TargetPath),
+	)
+
+	/* lock the file path for thread safety (ensure unlock even on panic) */
+	lock := getPathLock(txn.TargetPath)
+	lock.Lock()
+	defer lock.Unlock()
+
+	/* execute the ACL modifications with acl commands */
+	var cmd *exec.Cmd
+	switch txn.Entries.Action {
+	case "add", "modify":
+		cmd = exec.Command("setfacl", "-m", aclEntry, txn.TargetPath)
+	case "remove":
+		cmd = exec.Command("setfacl", "-x", aclEntry, txn.TargetPath)
+	default:
+		// sendResponse(conn, false, "Unsupported action: "+req.Action)
+		txn.ErrorMsg = fmt.Sprintf("unsupported ACL action: %s", txn.Entries.Action)
+	}
+
+	start := time.Now()
+	
+	output, err := cmd.CombinedOutput()
+
+	duration := time.Since(start).Milliseconds()
+
+	txn.Output = string(output)
+	txn.DurationMs = duration
+
+	if err != nil {
+		/* status of transaction is successful but execution failed */
+		txn.Status = types.StatusSuccess
+		txn.ExecStatus = false
+		txn.ErrorMsg = err.Error()
+
+		/* REMOVE THIS */
+		zap.L().Error("ACL command failed",
+			zap.String("Transaction ID", txn.ID.String()),
+			zap.String("Output", string(output)),
+			zap.Error(err),
+		)
+
+		txn.ErrorMsg = fmt.Sprintf("setfacl failed: %w, output: %s", err, output)
+	}
+
+	txn.Status = types.StatusSuccess
+	txn.ExecStatus = true
+
+	/* REMOVE THIS */
+	zap.L().Info("ACL command executed successfully",
+		zap.String("Transaction ID", txn.ID.String()),
+		zap.String("Output", string(output)),
+	)
+
+	return nil
+}
+
+/* builds the ACL entry string for setfacl */
+func BuildACLEntry(entry types.ACLEntry) string {
+	var sb strings.Builder
+
+	if entry.IsDefault {
+		sb.WriteString("default:")
+	}
+
+	sb.WriteString(entry.EntityType)
+	sb.WriteString(":")
+	sb.WriteString(entry.Entity)
+	sb.WriteString(":")
+	sb.WriteString(entry.Permissions)
+
+	return sb.String()
+}