Fix bug of keepAlive

Author: sutext

Demo/MQTTDemo.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -5,8 +5,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/sutext/swift-promise",
       "state" : {
-        "revision" : "a40b8d605aa55c74ec1631daad7a59a5ce5fb075",
-        "version" : "2.0.2"
+        "revision" : "7c60757445266d3432eff3cff05d479e16f6bbc6",
+        "version" : "2.1.0"
       }
     }
   ],

Sources/MQTT/Client.swift

@@ -303,9 +303,8 @@ extension MQTTClient{
             pinging?.update()
             var buffer = DataBuffer()
             try packet.write(version: config.version, to: &buffer)
-            return socket.send(data: buffer.data).then { _ in
-                self.pinging?.update()
-            }
+            self.pinging?.update()
+            return socket.send(data: buffer.data).then { _ in }
         } catch {
             return .init(error)
         }
@@ -336,9 +335,8 @@ extension MQTTClient{
             Logger.debug("SEND: \(packet)")
             var buffer = DataBuffer()
             try packet.write(version: config.version, to: &buffer)
-            
+            self.pinging?.update()
             return socket.send(data: buffer.data).then { _ in
-                self.pinging?.update()
                 return task.start(in: self.queue,timeout:timeout)
             }
         } catch {

Sources/MQTT/MQTT.swift

@@ -79,13 +79,6 @@ public final class Config:@unchecked Sendable{
             assert(pingTimeout>0, "pingTimeout must be greater than zero!")
         }
     }
-    ///The max times the connection consecutive ping timeouts
-    /// It will take effect immediately
-    public var maxPingCount:UInt8 = 1{
-        didSet{
-            assert(maxPingCount>0, "maxPingCount must be greater than zero!")
-        }
-    }
     /// timeout second  for connecting to server
     /// - Important: This setting does not take effect in the quic protocol. In the quic protocol is fixed at 30s and cannot be modified
     /// - Note:Please set this value before client open, otherwise it will take effect on the next open

Sources/MQTT/Retrier.swift

@@ -102,51 +102,47 @@ final class Monitor:@unchecked Sendable{
 final class Pinging:@unchecked Sendable{
     private let queue:DispatchQueue = .init(label: "mqtt.ping.queue")
     private let config:Config
-    private var tryCount:UInt8 = 0
-    private var lastTime:DispatchTime
-    private var item:DispatchWorkItem?
+    private var execTime:DispatchTime
+    private var worker:DispatchWorkItem?
     private weak var client:MQTTClient?
     init(client:MQTTClient){
-        lastTime = .now()
+        execTime = .now()
         config = client.config
         self.client = client
     }
     func start(){
         guard config.pingEnabled else { return }
-        guard item == nil else{ return }
-        tryCount = 0
-        lastTime = .now()
+        guard worker == nil else{ return }
+        execTime = .now()
         schedule()
     }
     func cancel(){
-        if item != nil{
-            item?.cancel()
-            item = nil
+        queue.async {
+            if self.worker != nil{
+                self.worker?.cancel()
+                self.worker = nil
+            }
         }
     }
     func update(){
-        lastTime = .now()
+        self.execTime = .now()
     }
     private func schedule(){
-        let item = DispatchWorkItem{[weak self] in
+        let worker = DispatchWorkItem{[weak self] in
             guard let self else{ return }
             guard let client = self.client else{ return }
-            if self.lastTime+TimeInterval(self.config.keepAlive) <= .now(){
-                client.ping().finally{result in
-                    if case .failure = result{
-                        self.tryCount += 1
-                        if self.tryCount >= self.config.maxPingCount{
-                            client.pingTimeout()
-                        }
-                    }
-                    self.update()
-                    self.schedule()
-                }
-            }else{
+            guard self.execTime+TimeInterval(self.config.keepAlive) <= .now() else{
                 self.schedule()
+                return
+            }
+            client.ping().finally{result in
+                if case .failure = result{
+                    client.pingTimeout()
+                }
             }
+            self.schedule()
         }
-        queue.asyncAfter(deadline: lastTime + TimeInterval(config.keepAlive), execute: item)
-        self.item = item
+        self.queue.asyncAfter(deadline: execTime + TimeInterval(config.keepAlive), execute: worker)
+        self.worker = worker
     }
 }

Sources/MQTT/Socket.swift

@@ -1,5 +1,5 @@
 //
-//  Connection.swift
+//  Socket.swift
 //  swift-mqtt
 //
 //  Created by supertext on 2025/3/7.