新增：trylock 尝试获取锁，并立即返回加锁结果

internal/zbus/zbus-message-handler.go

@@ -203,21 +203,21 @@ func messageHandler(v Message) {
 				}
 				Bus.shutdown()
 			}
-		case "lock":
+		case "lock", "trylock":
 			// lock key uuid 5
 			if len(rcmd) != 4 {
 				c.send("-Error: lock para number![" + strings.Join(rcmd, " ") + "]")
 				return
 			}
 			d, _ := strconv.Atoi(rcmd[3])
-			Bus._lock(&Lock{key: rcmd[1], uuid: rcmd[2], duration: d})
+			Bus._lock(&Lock{cmd: cmd, key: rcmd[1], uuid: rcmd[2], duration: d})
 		case "unlock":
 			// unlock key uuid
 			if len(rcmd) != 3 {
 				c.send("-Error: unlock para number![" + strings.Join(rcmd, " ") + "]")
 				return
 			}
-			Bus._unlock(Lock{key: rcmd[1], uuid: rcmd[2]})
+			Bus._unlock(Lock{cmd: cmd, key: rcmd[1], uuid: rcmd[2]})
 		default:
 			c.send("-Error: default not supported:[" + strings.Join(rcmd, " ") + "]")
 			return

internal/zbus/zbus.go

@@ -95,9 +95,10 @@ type ZConn struct { //ZConn
 }
 
 type Lock struct {
-	key      string
-	uuid     string
-	duration int
+	cmd      string // lock|trylock|unlock
+	key      string // lock key
+	uuid     string // apply for unique identification
+	duration int    // lock duration (seconds)
 	timer    *time.Timer
 	start    int64
 	//stop     time.Time
@@ -432,7 +433,12 @@ func (s *ZBus) _lock(lock *Lock) {
 			}
 		}()
 	} else {
-		s.locks[lock.key] = append(locks, lock)
+		switch lock.cmd {
+		case "trylock": // send trylock fail message
+			s.broadcast("trylock", lock.uuid)
+		case "lock":
+			s.locks[lock.key] = append(locks, lock)
+		}
 	}
 }
 func (s *ZBus) _unlock(l Lock) {

internal/zbus/zdb.go

@@ -161,6 +161,7 @@ func (s *ZBus) loadLock() {
 		}
 
 		s._lock(&Lock{
+			cmd:      "lock",
 			key:      split[0],
 			uuid:     split[1],
 			duration: duration,