fix lost messages / properties in TCPRequest Node; closes #1863 (#1864)

- Added some more checks around this.
- We're choosing to only use the latest message when sending, which is
  effectively what was happening before the queue implementation.

nodes/core/io/31-tcpin.js

@@ -467,6 +467,7 @@ module.exports = function(RED) {
                 connecting: false
             };
             enqueue(clients[connection_id].msgQueue, msg);
+            clients[connection_id].lastMsg = msg;
 
             if (!clients[connection_id].connecting && !clients[connection_id].connected) {
                 var buf;
@@ -507,8 +508,7 @@ module.exports = function(RED) {
                 clients[connection_id].client.on('data', function(data) {
                     if (node.out === "sit") { // if we are staying connected just send the buffer
                         if (clients[connection_id]) {
-                            let msg = dequeue(clients[connection_id].msgQueue) || {};
+                            const msg = clients[connection_id].lastMsg || {};
-                            clients[connection_id].msgQueue.unshift(msg);
                             msg.payload = data;
                             node.send(RED.util.cloneMessage(msg));
                         }
@@ -530,8 +530,7 @@ module.exports = function(RED) {
                                         clients[connection_id].timeout = setTimeout(function () {
                                             if (clients[connection_id]) {
                                                 clients[connection_id].timeout = null;
-                                                let msg = dequeue(clients[connection_id].msgQueue) || {};
+                                                const msg = clients[connection_id].lastMsg || {};
-                                                clients[connection_id].msgQueue.unshift(msg);
                                                 msg.payload = Buffer.alloc(i+1);
                                                 buf.copy(msg.payload,0,0,i+1);
                                                 node.send(msg);
@@ -553,8 +552,7 @@ module.exports = function(RED) {
                                 i += 1;
                                 if ( i >= node.splitc) {
                                     if (clients[connection_id]) {
-                                        let msg = dequeue(clients[connection_id].msgQueue) || {};
+                                        const msg = clients[connection_id].lastMsg || {};
-                                        clients[connection_id].msgQueue.unshift(msg);
                                         msg.payload = Buffer.alloc(i);
                                         buf.copy(msg.payload,0,0,i);
                                         node.send(msg);
@@ -573,8 +571,7 @@ module.exports = function(RED) {
                                 i += 1;
                                 if (data[j] == node.splitc) {
                                     if (clients[connection_id]) {
-                                        let msg = dequeue(clients[connection_id].msgQueue) || {};
+                                        const msg = clients[connection_id].lastMsg || {};
-                                        clients[connection_id].msgQueue.unshift(msg);
                                         msg.payload = Buffer.alloc(i);
                                         buf.copy(msg.payload,0,0,i);
                                         node.send(msg);

test/nodes/core/io/31-tcprequest_spec.js

@@ -59,7 +59,11 @@ describe('TCP Request Node', function() {
             var n2 = helper.getNode("n2");
             n2.on("input", function(msg) {
                 try {
-                    msg.should.have.property('payload', Buffer(val1));
+                    if (typeof val1 === 'object') {
+                        msg.should.have.properties(Object.assign({}, val1, {payload: Buffer(val1.payload)}));
+                    } else {
+                        msg.should.have.property('payload', Buffer(val1));
+                    }
                     done();
                 } catch(err) {
                     done(err);
@@ -79,7 +83,11 @@ describe('TCP Request Node', function() {
             const n2 = helper.getNode("n2");
             n2.on("input", msg => {
                 try {
-                    msg.should.have.property('payload', Buffer(result));
+                    if (typeof result === 'object') {
+                        msg.should.have.properties(Object.assign({}, result, {payload: Buffer(result.payload)}));
+                    } else {
+                        msg.should.have.property('payload', Buffer(result));
+                    }
                     done();
                 } catch(err) {
                     done(err);
@@ -95,31 +103,75 @@ describe('TCP Request Node', function() {
         it('should send & recv data', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"time", splitc: "0", wires:[["n2"]] },
             {id:"n2", type:"helper"}];
-            testTCP(flow, "foo", "ACK:foo", done)
+            testTCP(flow, {
+                payload: 'foo',
+                topic: 'bar'
+            }, {
+                payload: 'ACK:foo',
+                topic: 'bar'
+            }, done);
+        });
+
+        it('should retain complete message', function(done) {
+            var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"time", splitc: "0", wires:[["n2"]] },
+            {id:"n2", type:"helper"}];
+            testTCP(flow, {
+                payload: 'foo',
+                topic: 'bar'
+            }, {
+                payload: 'ACK:foo',
+                topic: 'bar'
+            }, done);
         });
 
         it('should send & recv data when specified character received', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"char", splitc: "0", wires:[["n2"]] },
             {id:"n2", type:"helper"}];
-            testTCP(flow, "foo0bar0", "ACK:foo0", done);
+            testTCP(flow, {
+                payload: 'foo0bar0',
+                topic: 'bar'
+            }, {
+                payload: 'ACK:foo0',
+                topic: 'bar'
+            }, done);
         });
 
         it('should send & recv data after fixed number of chars received', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"count", splitc: "7", wires:[["n2"]] },
             {id:"n2", type:"helper"}];
-            testTCP(flow, "foo bar", "ACK:foo", done);
+            testTCP(flow, {
+                payload: 'foo bar',
+                topic: 'bar'
+            }, {
+                payload: 'ACK:foo',
+                topic: 'bar'
+            }, done);
         });
 
         it('should send & receive, then keep connection', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"sit", splitc: "5", wires:[["n2"]] },
             {id:"n2", type:"helper"}];
-            testTCP(flow, "foo", "ACK:foo", done);
+            testTCP(flow, {
+                payload: 'foo',
+                topic: 'bar'
+            }, {
+                payload: 'ACK:foo',
+                topic: 'bar'
+            }, done);
         });
 
         it('should send & recv data to/from server:port from msg', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"", port:"", out:"time", splitc: "0", wires:[["n2"]] },
             {id:"n2", type:"helper"}];
-            testTCP(flow, {payload:"foo", host:"localhost", port:port}, "ACK:foo", done)
+            testTCP(flow, {
+                payload: "foo",
+                host: "localhost",
+                port: port
+            }, {
+                payload: "ACK:foo",
+                host: 'localhost',
+                port: port
+            }, done);
         });
     });
 
@@ -127,36 +179,95 @@ describe('TCP Request Node', function() {
         it('should send & recv data', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"time", splitc: "0", wires:[["n2"]] },
                         {id:"n2", type:"helper"}];
-
+            testTCPMany(flow, [{
-            testTCPMany(flow, ['f', 'o', 'o'], 'ACK:foo', done);
+                payload: 'f',
+                topic: 'bar'
+            }, {
+                payload: 'o',
+                topic: 'bar'
+            }, {
+                payload: 'o',
+                topic: 'bar'
+            }], {
+                payload: 'ACK:foo',
+                topic: 'bar'
+            }, done);
         });
 
         it('should send & recv data when specified character received', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"char", splitc: "0", wires:[["n2"]] },
                         {id:"n2", type:"helper"}];
-            testTCPMany(flow, ["foo0","bar0"], "ACK:foo0", done);
+            testTCPMany(flow, [{
+                payload: "foo0",
+                topic: 'bar'
+            }, {
+                payload: "bar0",
+                topic: 'bar'
+            }], {
+                payload: "ACK:foo0",
+                topic: 'bar'
+            }, done);
         });
 
         it('should send & recv data after fixed number of chars received', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"count", splitc: "7", wires:[["n2"]] },
                         {id:"n2", type:"helper"}];
-            testTCPMany(flow, ["fo", "ob", "ar"], "ACK:foo", done);
+            testTCPMany(flow, [{
+                payload: "fo",
+                topic: 'bar'
+            }, {
+                payload: "ob",
+                topic: 'bar'
+            }, {
+                payload: "ar",
+                topic: 'bar'
+            }], {
+                payload: "ACK:foo",
+                topic: 'bar'
+            }, done);
         });
 
-
         it('should send & receive, then keep connection', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"sit", splitc: "5", wires:[["n2"]] },
                         {id:"n2", type:"helper"}];
-            testTCPMany(flow, ["foo", "bar", "baz"], "ACK:foobarbaz", done);
+            testTCPMany(flow, [{
+                payload: "foo",
+                topic: 'bar'
+            }, {
+                payload: "bar",
+                topic: 'bar'
+            }, {
+                payload: "baz",
+                topic: 'bar'
+            }], {
+                payload: "ACK:foobarbaz",
+                topic: 'bar'
+            }, done);
         });
 
         it('should send & recv data to/from server:port from msg', function(done) {
             var flow = [{id:"n1", type:"tcp request", server:"", port:"", out:"time", splitc: "0", wires:[["n2"]] },
                         {id:"n2", type:"helper"}];
-            testTCPMany(flow, [
+            testTCPMany(flow, [{
-                {payload:"f", host:"localhost", port:port},
+                    payload: "f",
-                {payload:"o", host:"localhost", port:port},
+                    host: "localhost",
-                {payload:"o", host:"localhost", port:port}], "ACK:foo", done);
+                    port: port
+                },
+                {
+                    payload: "o",
+                    host: "localhost",
+                    port: port
+                },
+                {
+                    payload: "o",
+                    host: "localhost",
+                    port: port
+                }
+            ], {
+                payload: "ACK:foo",
+                host: 'localhost',
+                port: port
+            }, done);
         });
 
         it('should limit the queue size', function (done) {
@@ -168,5 +279,23 @@ describe('TCP Request Node', function() {
             const expected = msgs.slice(0, -1);
             testTCPMany(flow, msgs, "ACK:" + expected.join(''), done);
         });
+
+        it('should only retain the latest message', function(done) {
+            var flow = [{id:"n1", type:"tcp request", server:"localhost", port:port, out:"time", splitc: "0", wires:[["n2"]] },
+                        {id:"n2", type:"helper"}];
+            testTCPMany(flow, [{
+                payload: 'f',
+                topic: 'bar'
+            }, {
+                payload: 'o',
+                topic: 'baz'
+            }, {
+                payload: 'o',
+                topic: 'quux'
+            }], {
+                payload: 'ACK:foo',
+                topic: 'quux'
+            }, done);
+        });
     });
 });