Make sendStats customizable

lib/express-statsd.js

@@ -3,10 +3,25 @@ var extend = require('obj-extend');
 var Lynx = require('lynx');
 
 module.exports = function expressStatsdInit (options) {
+  // Function called on response finish that sends stats to statsd
+  function sendStats(req, res, client, startTime, options) {
+    var key = req[options.requestKey];
+    key = key ? key + '.' : '';
+
+    // Status Code
+    var statusCode = res.statusCode || 'unknown_status';
+    client.increment(key + 'status_code.' + statusCode);
+
+    // Response Time
+    var duration = new Date().getTime() - startTime;
+    client.timing(key + 'response_time', duration);
+  }
+
   options = extend({
     requestKey: 'statsdKey',
     host: '127.0.0.1',
-    port: 8125
+    port: 8125,
+    sendStats: sendStats
   }, options);
 
   assert(options.requestKey, 'express-statsd expects a requestKey');
@@ -16,31 +31,20 @@ module.exports = function expressStatsdInit (options) {
   return function expressStatsd (req, res, next) {
     var startTime = new Date().getTime();
 
-    // Function called on response finish that sends stats to statsd
-    function sendStats() {
-      var key = req[options.requestKey];
-      key = key ? key + '.' : '';
-
-      // Status Code
-      var statusCode = res.statusCode || 'unknown_status';
-      client.increment(key + 'status_code.' + statusCode);
-
-      // Response Time
-      var duration = new Date().getTime() - startTime;
-      client.timing(key + 'response_time', duration);
-
+    function send () {
+      options.sendStats(req, res, client, startTime, options);
       cleanup();
     }
 
     // Function to clean up the listeners we've added
     function cleanup() {
-      res.removeListener('finish', sendStats);
+      res.removeListener('finish', send);
       res.removeListener('error', cleanup);
       res.removeListener('close', cleanup);
     }
 
     // Add response listeners
-    res.once('finish', sendStats);
+    res.once('finish', send);
     res.once('error', cleanup);
     res.once('close', cleanup);
 

test/express-statsd.js

@@ -99,6 +99,34 @@ describe('An express server', function () {
       });
     });
 
+    describe('with a custom sendStats function', function () {
+      utils.runServer(1337, [
+        expressStatsd({
+          sendStats: function (req, res, client, startTime, options) {
+            var statusCode = res.statusCode;
+            client.increment('node_test.int.' + statusCode);
+            client.decrement('node_test.int.fail');
+            client.timing('node_test.some_service.task.time', 500);
+            client.gauge('gauge.one', 100);
+            client.set('set.one', 10);
+          }
+        }),
+        function (req, res) {
+          res.send(200);
+        }
+      ]);
+      utils.saveRequest('http://localhost:1337');
+      utils.getStatsdMessages();
+
+      it('should read from that key', function () {
+        expect(this.messages[0]).to.match(/^node_test\.int\.200:\d\|c$/);
+        expect(this.messages[1]).to.match(/^node_test\.int\.fail:-1\|c$/);
+        expect(this.messages[2]).to.match(/^node_test\.some_service\.task\.time:\d|ms$/);
+        expect(this.messages[3]).to.match(/^gauge\.one:100|g$/);
+        expect(this.messages[4]).to.match(/^set\.one:10|s$/);
+      });
+    });
+
     describe('receiving a request with a custom lynx', function () {
       utils.runServer(1337, [
         function (req, res, next) {