add command plugin

README.md

@@ -233,5 +233,20 @@ source = funnel.nagios({
 
 You'll notice that `funnel.ALL` is used here, too. This collects all performance data under this heading. `from` can be an array (or a string for a single server, but you *are* running MongoDB in a replica set, right? (-: ).
 
+### command ###
+
+This plugin allows you to run arbitrary commands to fetch metrics.
+
+```javascript
+source = funnel.command({
+    services: {
+        'seconds': function (stdout) { return parseInt(stdout); },
+    },
+    from: 'date +%s'
+});
+```
+
+
+
 
 

funnel.js

@@ -59,6 +59,7 @@ module.exports = {
     json: require('./plugin/json'),
     cloudwatch: require('./plugin/cloudwatch'),
     dbi: require('./plugin/dbi'),
+    command: require('./plugin/command'),
 
     COUNT: shared.COUNT,
     ALL: shared.ALL,

plugin/command.js

@@ -0,0 +1,38 @@
+var shared = require('./shared');
+
+module.exports = function (service) {
+    var sys = require('sys')
+    var exec = require('child_process').exec;
+    var hostname = require('os').hostname().split('.')[0];
+    return function (funneler) {
+        var from = service.from;
+        // cast to array
+        if (typeof from == 'string') {
+            from = [from];
+        }
+        from.forEach(function (cmd) {
+            for (var sName in service.services) {
+                (function (serviceName) { // yum! delicious scope!
+                    exec(cmd, function (error, stdout, stderr) {
+                        if (error) {
+                            console.log("Error.")
+                            console.log("stdout:")
+                            console.log(stdout)
+                            console.log("stderr:")
+                            console.log(stderr)
+                            return false;
+                        }
+                        funneler({
+                            'funnel': 'command',
+                            'nodeName': hostname,
+                            'serviceName': sName,
+                            'metricName': cmd,
+                            'reading': service.services[sName](stdout),
+                        });
+                    });
+                })(sName);
+            }
+        });
+    }
+};
+