add kill and start parameters to daemon node

utility/daemon/README.md

@@ -31,8 +31,13 @@ The command provides 3 outputs... stdout, stderr, and return code, from the runn
 If the called program stops (i.e. a return code is produced), this node can attempt
 to restart the command automatically.
 
-**Note :** when you stop Node-RED running we may not get a chance to kill the
+Setting `msg.kill` to a signal name (e.g. SIGINT, SIGHUP) will stop the process - but if the restart flag is set it will then auto restart.
-called program so it may remain running. You <i>may</i> have to kill it manually.
+
+Sending `msg.start` will also re-start the process.
+
+**Note:** Some applications will automatically buffer lines of output. It is advisable to turn off this behaviour.
+For example, if running a Python app, the `-u` parameter will stop the output being buffered.
+
 
 For example it can be used to run and then monitor the
 <a href="https://github.com/antirez/dump1090" target="_new">dump1090</a> plane

utility/daemon/daemon.html

@@ -40,9 +40,10 @@
     <p>Calls out to a long running system command. Sends <code>msg.payload</code> to stdin of the process.</p>
     <p>Provides 3 outputs... stdout, stderr, and return code , from the running command.</p>
     <p>If the called program stops (i.e. a return code is produced), this node can attempt to restart the command.</p>
-    <p><b>Note :</b> when you stop Node-RED running we may not get a chance to kill the called program so it may remain
+    <p>Setting <code>msg.kill</code> to a signal name (e.g. SIGINT, SIGHUP) will stop the process - but if the
-    running. You <i>may</i> have to kill it manually.</p>
+    restart flag is set it will then auto restart. Sending <code>msg.start</code> will also re-start the process.</p>
-    <p>If running a Python app you may need to use the <code>-u</code> parameter to stop the output being buffered.</p>
+    <p><b>Note:</b> Some applications will automatically buffer lines of output. It is advisable to turn off this behaviour.
+    For example, if running a Python app, the <code>-u</code> parameter will stop the output being buffered.</p>
 </script>
 
 <script type="text/javascript">

utility/daemon/daemon.js

@@ -15,14 +15,23 @@ module.exports = function(RED) {
 
         function inputlistener(msg) {
             if (msg != null) {
-                if (!Buffer.isBuffer(msg.payload)) {
+                if (msg.hasOwnProperty("kill") && node.running) {
-                    if (typeof msg.payload === "object") { msg.payload = JSON.stringify(msg.payload); }
+                    if (typeof msg.kill !== "string" || msg.kill.length === 0 || !msg.kill.toUpperCase().startsWith("SIG") ) { msg.kill = "SIGINT"; }
-                    if (typeof msg.payload !== "string") { msg.payload = msg.payload.toString(); }
+                    node.child.kill(msg.kill.toUpperCase());
-                    if (node.cr === true) { msg.payload += "\n"; }
+                }
+                else if (msg.hasOwnProperty("start") && !node.running) {
+                    runit();
+                }
+                else {
+                    if (!Buffer.isBuffer(msg.payload)) {
+                        if (typeof msg.payload === "object") { msg.payload = JSON.stringify(msg.payload); }
+                        if (typeof msg.payload !== "string") { msg.payload = msg.payload.toString(); }
+                        if (node.cr === true) { msg.payload += "\n"; }
+                    }
+                    if (RED.settings.verbose) { node.log("inp: "+msg.payload); }
+                    if (node.child !== null && node.running) { node.child.stdin.write(msg.payload); }
+                    else { node.warn("Command not running"); }
                 }
-                if (RED.settings.verbose) { node.log("inp: "+msg.payload); }
-                if (node.child !== null) { node.child.stdin.write(msg.payload); }
-                else { node.warn("Command not running"); }
             }
         }
 
@@ -61,11 +70,13 @@ module.exports = function(RED) {
                 node.send([null,{payload:data},null]);
             });
 
-            node.child.on('close', function (code) {
+            node.child.on('close', function (code,signal) {
-                if (RED.settings.verbose) { node.log("ret: "+code); }
+                if (RED.settings.verbose) { node.log("ret: "+code+":"+signal); }
-                node.send([null,null,{payload:code}]);
-                node.child = null;
                 node.running = false;
+                node.child = null;
+                var rc = code;
+                if (code === null) { rc = signal; }
+                node.send([null,null,{payload:rc}]);
                 node.status({fill:"red",shape:"ring",text:"stopped"});
             });
 

utility/daemon/package.json

@@ -1,6 +1,6 @@
 {
     "name"          : "node-red-node-daemon",
-    "version"       : "0.0.11",
+    "version"       : "0.0.14",
     "description"   : "A Node-RED node that runs and monitors a long running system command.",
     "dependencies"  : {
     },