Better error catching in ping node for spawn errors...

io/ping/88-ping.js

@@ -18,6 +18,7 @@ module.exports = function(RED) {
             else { node.error("Sorry - your platform - "+plat+" - is not recognised."); }
             var res = false;
             var line = "";
+            var fail = false;
             //var regex = /from.*time.(.*)ms/;
             var regex = /=.*[<|=]([0-9]*).*TTL|ttl..*=([0-9\.]*)/;
             ex.stdout.on('data', function (data) {
@@ -26,7 +27,20 @@ module.exports = function(RED) {
             //ex.stderr.on('data', function (data) {
             //console.log('[ping] stderr: ' + data);
             //});
+            ex.on('error', function (err) {
+                fail = true;
+                if (err.code === "ENOENT") {
+                    node.error(err.code + " ping command not found");
+                }
+                else if (err.code === "EACCES") {
+                    node.error(err.code + " can't run ping command");
+                }
+                else {
+                    node.error(err.code);
+                }
+            });
             ex.on('close', function (code) {
+                if (fail) { fail = false; return; }
                 var m = regex.exec(line)||"";
                 if (m !== '') {
                     if (m[1]) { res = Number(m[1]); }

io/ping/README.md

@@ -11,9 +11,11 @@ Run the following command in your Node-RED user directory - typically `~/.node-r
 
     npm install node-red-node-ping
 
-**Gotcha**
+**Gotchas**
 
-On some versions on Raspbian (Raspberry Pi) `ping` seems to be a root only command.
+ 1 This won't run on Ubunti Snap as the strict container does not allow spawning of external commands (like ping).
+
+ 2 On some versions on Raspbian (Raspberry Pi) `ping` seems to be a root only command.
 The fix is to allow it as follows
 
     sudo setcap cap_net_raw=ep /bin/ping

io/ping/package.json

@@ -1,6 +1,6 @@
 {
     "name"          : "node-red-node-ping",
-    "version"       : "0.0.15",
+    "version"       : "0.0.16",
     "description"   : "A Node-RED node to ping a remote server, for use as a keep-alive check.",
     "dependencies"  : {
     },