More resilient binding to correct port for udp, give input side priority

packages/node_modules/@node-red/nodes/core/io/32-udp.js

@@ -58,17 +58,36 @@ module.exports = function(RED) {
         if (process.version.indexOf("v0.10") === 0) { opts = node.ipv; }
         var server;
 
-        if (!udpInputPortsInUse.hasOwnProperty(this.port)) {
+        if (!udpInputPortsInUse.hasOwnProperty(node.port)) {
             server = dgram.createSocket(opts);  // default to udp4
-            udpInputPortsInUse[this.port] = server;
+            server.bind(node.port, function() {
+                if (node.multicast == "true") {
+                    server.setBroadcast(true);
+                    server.setMulticastLoopback(false);
+                    try {
+                        server.setMulticastTTL(128);
+                        server.addMembership(node.group,node.iface);
+                        if (node.iface) { node.status({text:n.iface+" : "+node.iface}); }
+                        node.log(RED._("udp.status.mc-group",{group:node.group}));
+                    } catch (e) {
+                        if (e.errno == "EINVAL") {
+                            node.error(RED._("udp.errors.bad-mcaddress"));
+                        } else if (e.errno == "ENODEV") {
+                            node.error(RED._("udp.errors.interface"));
+                        } else {
+                            node.error(RED._("udp.errors.error",{error:e.errno}));
+                        }
+                    }
+                }
+            });
+            udpInputPortsInUse[node.port] = server;
         }
         else {
             node.log(RED._("udp.errors.alreadyused",{port:node.port}));
-            server = udpInputPortsInUse[this.port];  // re-use existing
+            server = udpInputPortsInUse[node.port];  // re-use existing
+            if (node.iface) { node.status({text:n.iface+" : "+node.iface}); }
         }
 
-        if (process.version.indexOf("v0.10") === 0) { opts = node.ipv; }
-
         server.on("error", function (err) {
             if ((err.code == "EACCES") && (node.port < 1024)) {
                 node.error(RED._("udp.errors.access-error"));
@@ -92,39 +111,24 @@ module.exports = function(RED) {
 
         server.on('listening', function () {
             var address = server.address();
-            node.log(RED._("udp.status.listener-at",{host:address.address,port:address.port}));
+            node.log(RED._("udp.status.listener-at",{host:node.iface||address.address,port:address.port}));
-            if (node.multicast == "true") {
+
-                server.setBroadcast(true);
-                try {
-                    server.setMulticastTTL(128);
-                    server.addMembership(node.group,node.iface);
-                    node.log(RED._("udp.status.mc-group",{group:node.group}));
-                } catch (e) {
-                    if (e.errno == "EINVAL") {
-                        node.error(RED._("udp.errors.bad-mcaddress"));
-                    } else if (e.errno == "ENODEV") {
-                        node.error(RED._("udp.errors.interface"));
-                    } else {
-                        node.error(RED._("udp.errors.error",{error:e.errno}));
-                    }
-                }
-            }
         });
 
         node.on("close", function() {
-            if (udpInputPortsInUse.hasOwnProperty(node.port)) {
-                delete udpInputPortsInUse[node.port];
-            }
             try {
+                if (node.multicast == "true") { server.dropMembership(node.group); }
                 server.close();
                 node.log(RED._("udp.status.listener-stopped"));
             } catch (err) {
                 //node.error(err);
             }
+            if (udpInputPortsInUse.hasOwnProperty(node.port)) {
+                delete udpInputPortsInUse[node.port];
+            }
+            node.status({});
         });
 
-        try { server.bind(node.port,node.iface); }
-        catch(e) { } // Don't worry if already bound
     }
     RED.httpAdmin.get('/udp-ports/:id', RED.auth.needsPermission('udp-ports.read'), function(req,res) {
         res.json(Object.keys(udpInputPortsInUse));
@@ -132,6 +136,7 @@ module.exports = function(RED) {
     RED.nodes.registerType("udp in",UDPin);
 
 
+
     // The Output Node
     function UDPout(n) {
         RED.nodes.createNode(this,n);
@@ -169,31 +174,26 @@ module.exports = function(RED) {
         }
 
         var opts = {type:node.ipv, reuseAddr:true};
-        if (process.version.indexOf("v0.10") === 0) { opts = node.ipv; }
 
         var sock;
         var p = this.outport || this.port || "0";
+        node.tout = setTimeout(function() {
             if (udpInputPortsInUse[p]) {
                 sock = udpInputPortsInUse[p];
                 node.log(RED._("udp.status.re-use",{outport:node.outport,host:node.addr,port:node.port}));
+                if (node.iface) { node.status({text:n.iface+" : "+node.iface}); }
             }
             else {
                 sock = dgram.createSocket(opts);  // default to udp4
-            sock.on("error", function(err) {
-                // Any async error will also get reported in the sock.send call.
-                // This handler is needed to ensure the error marked as handled to
-                // prevent it going to the global error handler and shutting node-red
-                // down.
-            });
-            udpInputPortsInUse[p] = sock;
-
                 if (node.multicast != "false") {
                     sock.bind(node.outport, function() {    // have to bind before you can enable broadcast...
                         sock.setBroadcast(true);            // turn on broadcast
+                        sock.setMulticastLoopback(false);   // turn off loopback
                         if (node.multicast == "multi") {
                             try {
                                 sock.setMulticastTTL(128);
                                 sock.addMembership(node.addr,node.iface);   // Add to the multicast group
+                                if (node.iface) { node.status({text:n.iface+" : "+node.iface}); }
                                 node.log(RED._("udp.status.mc-ready",{iface:node.iface,outport:node.outport,host:node.addr,port:node.port}));
                             } catch (e) {
                                 if (e.errno == "EINVAL") {
@@ -214,6 +214,14 @@ module.exports = function(RED) {
                 } else {
                     node.log(RED._("udp.status.ready-nolocal",{host:node.addr,port:node.port}));
                 }
+                sock.on("error", function(err) {
+                    // Any async error will also get reported in the sock.send call.
+                    // This handler is needed to ensure the error marked as handled to
+                    // prevent it going to the global error handler and shutting node-red
+                    // down.
+                });
+                udpInputPortsInUse[p] = sock;
+            }
         }
 
             node.on("input", function(msg) {
@@ -244,17 +252,21 @@ module.exports = function(RED) {
                     }
                 }
             });
+        }, 150);
 
         node.on("close", function() {
-            if (udpInputPortsInUse.hasOwnProperty(p)) {
+            if (node.tout) { clearTimeout(node.tout); }
-                delete udpInputPortsInUse[p];
-            }
             try {
+                if (node.multicast == "multi") { sock.dropMembership(node.group); }
                 sock.close();
                 node.log(RED._("udp.status.output-stopped"));
             } catch (err) {
                 //node.error(err);
             }
+            if (udpInputPortsInUse.hasOwnProperty(p)) {
+                delete udpInputPortsInUse[p];
+            }
+            node.status({});
         });
     }
     RED.nodes.registerType("udp out",UDPout);