first commit

app/stats/client.js

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+'use strict';
+
+var _ = require('underscore');
+var debug = require('debug')('windshaft:stats_client');
+var StatsD = require('node-statsd').StatsD;
+
+module.exports = {
+    /**
+     * Returns an StatsD instance or an stub object that replicates the StatsD public interface so there is no need to
+     * keep checking if the stats_client is instantiated or not.
+     *
+     * The first call to this method implies all future calls will use the config specified in the very first call.
+     *
+     * TODO: It's far from ideal to use make this a singleton, improvement desired.
+     * We proceed this way to be able to use StatsD from several places sharing one single StatsD instance.
+     *
+     * @param config Configuration for StatsD, if undefined it will return an stub
+     * @returns {StatsD|Object}
+     */
+    getInstance: function(config) {
+
+        if (!this.instance) {
+
+            var instance;
+
+            if (config) {
+                instance = new StatsD(config);
+                instance.last_error = { msg: '', count: 0 };
+                instance.socket.on('error', function (err) {
+                    var last_err = instance.last_error;
+                    var last_msg = last_err.msg;
+                    var this_msg = '' + err;
+                    if (this_msg !== last_msg) {
+                        debug("statsd client socket error: " + err);
+                        instance.last_error.count = 1;
+                        instance.last_error.msg = this_msg;
+                    } else {
+                        ++last_err.count;
+                        if (!last_err.interval) {
+                            instance.last_error.interval = setInterval(function () {
+                                var count = instance.last_error.count;
+                                if (count > 1) {
+                                    debug("last statsd client socket error repeated " + count + " times");
+                                    instance.last_error.count = 1;
+                                    clearInterval(instance.last_error.interval);
+                                    instance.last_error.interval = null;
+                                }
+                            }, 1000);
+                        }
+                    }
+                });
+            } else {
+                var stubFunc = function (stat, value, sampleRate, callback) {
+                    if (_.isFunction(callback)) {
+                        callback(null, 0);
+                    }
+                };
+                instance = {
+                    timing: stubFunc,
+                    increment: stubFunc,
+                    decrement: stubFunc,
+                    gauge: stubFunc,
+                    unique: stubFunc,
+                    set: stubFunc,
+                    sendAll: stubFunc,
+                    send: stubFunc
+                };
+            }
+
+            this.instance = instance;
+        }
+
+        return this.instance;
+    }
+};

app/stats/profiler-proxy.js

@@ -0,0 +1,55 @@
+'use strict';
+
+var Profiler = require('step-profiler');
+
+/**
+ * Proxy to encapsulate node-step-profiler module so there is no need to check if there is an instance
+ */
+function ProfilerProxy(opts) {
+    this.profile = !!opts.profile;
+
+    this.profiler = null;
+    if (!!opts.profile) {
+        this.profiler = new Profiler({statsd_client: opts.statsd_client});
+    }
+}
+
+ProfilerProxy.prototype.done = function(what) {
+    if (this.profile) {
+        this.profiler.done(what);
+    }
+};
+
+ProfilerProxy.prototype.end = function() {
+    if (this.profile) {
+        this.profiler.end();
+    }
+};
+
+ProfilerProxy.prototype.start = function(what) {
+    if (this.profile) {
+        this.profiler.start(what);
+    }
+};
+
+ProfilerProxy.prototype.add = function(what) {
+    if (this.profile) {
+        this.profiler.add(what || {});
+    }
+};
+
+ProfilerProxy.prototype.sendStats = function() {
+    if (this.profile) {
+        this.profiler.sendStats();
+    }
+};
+
+ProfilerProxy.prototype.toString = function() {
+    return this.profile ? this.profiler.toString() : "";
+};
+
+ProfilerProxy.prototype.toJSONString = function() {
+    return this.profile ? this.profiler.toJSONString() : "{}";
+};
+
+module.exports = ProfilerProxy;