update: 优化mqtt2.lua,再添加点注释

bsp/air640w/demo/73.mqtt2/main.lua

@@ -72,25 +72,25 @@ sys.taskInit(function()
 end)
 
 sys.taskInit(function()
-    local host, port, selfid = "lbsmqtt.airm2m.com", 1884, wlan.getMac():lower()
+    local host, port, clientId = "lbsmqtt.airm2m.com", 1884, wlan.getMac():lower()
 
-    local topic_req = string.format("/device/%s/req", selfid)
-    local topic_report = string.format("/device/%s/report", selfid)
-    local topic_resp = string.format("/device/%s/resp", selfid)
+    local topic_req = string.format("/device/%s/req", clientId)
+    local topic_report = string.format("/device/%s/report", clientId)
+    local topic_resp = string.format("/device/%s/resp", clientId)
 
     local sub_topics = {}
     sub_topics[topic_req] = 1
 
-    local mqttc = mqtt2.new(selfid, 300, "wendal", "123456", 0, host, port, sub_topics, function(pkg)
+    local mqttc = mqtt2.new(clientId, 300, "wendal", "123456", 1, host, port, sub_topics, function(pkg)
         log.info("mqtt", "Oh", json.encode(pkg))
-    end)
+    end, "mqtt_airm2m")
 
     --log.info("mqtt", json.encode(mqttc))
 
     while not socket.isReady() do sys.waitUntil("NET_READY", 1000) end
     sys.wait(3000)
     log.info("go", "GoGoGo")
-    mqttc:start()
+    mqttc:run() -- 会一直阻塞在这里
 end)
 
 

bsp/air640w/lib/mqtt2.lua

@@ -73,38 +73,40 @@ local mqtt2 = {}
 local mqttc = {}
 mqttc.__index = mqttc
 
-function mqtt2.new(clientId, keepAlive, username, password, cleanSession, host, port, topics, cb)
+function mqtt2.new(clientId, keepAlive, username, password, cleanSession, host, port, topics, cb, ckey)
     local c = {
         clientId = clientId,
         keepAlive = keepAlive or 300,
         username = username or "",
         password = password or "",
-        cleanSession = cleanSession,
+        cleanSession = cleanSession == nil and 1 or 0,
         host = host,
         port = port,
         lping = 0,
         stat = 0, -- 状态 0, 未连接, 1 已连接成功
         nextid = 0, -- pkg的ID
-        running = true,
-        ckey = "",
+        running = false,
         inpkgs = {},
         outpkgs = {},
         buff = "",
         topics = topics or {},
-        cb = cb
+        cb = cb,
+        ckey = ckey or ""
     }
-    c.ckey = "mqtt_" .. tostring(c)
+    if c.ckey == "" then c.ckey = "mqtt_" .. tostring(c) end
     --mclog("mqtt", "MQTT Client Key", c.ckey)
     setmetatable(c, mqttc)
     return c
 end
 
+-- 内部方法, 用于获取下一个pkg的id
 function mqttc:genId()
     self.nextid = self.nextid == 65535 and 1 or (self.nextid + 1)
     --mclog("mqtt", "next packet id", self.nextid)
     return self.nextid
 end
 
+-- 内部方法,用于处理待处理的数据包
 function mqttc:handle(netc)
     local mc = self
     -- 先处理服务器下发的数据包
@@ -173,10 +175,17 @@ function mqttc:handle(netc)
     end
 end
 
-function mqttc:start()
+-- 启动mqtt task, 要么在task里面执行, 要么新建一个task执行本方法
+function mqttc:run()
     local mc = self
+    mc.running = true
     while mc.running do
         if socket.isReady() then
+            -- 先复位全部临时对象
+            mc.buff = ""
+            mc.inpkgs = {}
+            mc.outpkgs = {}
+            -- 建立socket对象
             --mclog("mqtt", "try connect")
             local netc = socket.tcp()
             netc:host(mc.host)
@@ -223,11 +232,13 @@ function mqttc:start()
                     --mclog("mqtt", "handle/timeout/ping", (netc:closed()))
                 end
             end
-            mc.stat = 0
             -- 清理socket上下文
             mclog("mqtt", "clean up")
             netc:clean()
             netc:close()
+            -- 将所有状态复位
+            mc.stat = 0
+
             mclog("mqtt", "wait 5s for next loop")
             sys.wait(5*1000) -- TODO 使用级数递增进行延时
         else
@@ -238,12 +249,14 @@ function mqttc:start()
     mclog("mqtt", self.ckey, "exit")
 end
 
+-- 订阅topic, table形式
 function mqttc:sub(topics)
     table.insert(self.outpkgs, packSUBSCRIBE(0, self:genId(), topics))
     sys.publish(self.ckey)
     return sys.waitUntil(self.ckey .. "SUBACK", 30000)
 end
 
+-- 上报数据
 function mqttc:pub(topic, qos, payload)
     -- local function packPUBLISH(dup, qos, retain, packetId, topic, payload)
     table.insert(self.outpkgs, packPUBLISH(0, qos, 0, qos and self:genId() or 0, topic, payload))