fix[backend]: 修复"帧头和长度"获取帧数据的逻辑

static/server/app.js

@@ -112,6 +112,8 @@ io.sockets.on('connection', function (socket) {
 
 })
 
+const frame_header_and_size_bytes = 1 + 2;
+
 socketServer.on('connection',(socket)=>{
     console.log('连接已建立')
     socketEvent = socket
@@ -128,19 +130,27 @@ socketServer.on('connection',(socket)=>{
         if (lastBuffer !== null) {
             data = Buffer.concat([lastBuffer, data]);
         }
+
         let flag = 1;
         while(flag){
-            let validNumByteArray = new Uint8Array(data.slice(1, 3));
-            let validNum = validNumByteArray[0]
-            if(data.length >validNum) {
-                let validateData = data.slice(0, 1 + 2 +validNum);
-                setAllCommand(validateData)
-                lastBuffer = data.slice(1+2+validNum)
-                if(lastBuffer.length >=1+2+validNum) {
+            if (data.length < frame_header_and_size_bytes) {
+                lastBuffer = data;
+                break;
+            }
+
+            let dataLength = data.readUIntLE(1, 2)
+            let frameLength = frame_header_and_size_bytes + dataLength
+
+            if(data.length > frameLength) {
+                let frame = data.slice(0, frameLength);
+                setAllCommand(frame)
+                lastBuffer = data.slice(frameLength)
+
+                if(lastBuffer.length >= frame_header_and_size_bytes) {
                     data = lastBuffer
                     continue;
                 }
-            } else if(data.length == 1+2+validNum) {
+            } else if(data.length === frameLength) {
                 setAllCommand(data)
                 lastBuffer = null;
             } else {
@@ -148,7 +158,6 @@ socketServer.on('connection',(socket)=>{
             }
             flag = 0;
         }
-        // 处理压力板发过来的数据
     });
     socket.on('error', (err)=>{
         console.warn(err);
@@ -156,7 +165,6 @@ socketServer.on('connection',(socket)=>{
     });
     socket.on('end', ()=>{
         io.sockets.emit('disConnectOneClient');
-        //socketServer.close();
     });
 })