Use settimeout unref conditionally

README.md

@@ -120,6 +120,8 @@ Where `options` is an object and can contain the following:
 * `defaultTags`: Default tags used for all metric reporting. (optional)
     * Set tags that are common to all metrics.
 * `agent`: custom https agent (optional)
+* `apiHost`: Sets the hostname of the target API endpoint. (optional)
+    * Defaults to `api.datadoghq.com`
 
 
 Example:

lib/loggers.js

@@ -26,8 +26,10 @@ var Histogram = require('./metrics').Histogram;
 //     - apiKey: DataDog API key
 //     - appKey: DataDog APP key
 //     - host: Default host for all reported metrics
+//     - apiHost: Hostname dogapi uses to send metrics to
 //     - prefix: Default key prefix for all metrics
 //     - agent: a https agent, passed as dogapi's proxy_agent
+//     - intervalHandler: alternative interval handler vs. default setTimeout
 //     - flushIntervalSeconds:
 //
 // You can also use it to override (dependency-inject) the aggregator
@@ -38,10 +40,13 @@ var Histogram = require('./metrics').Histogram;
 //
 function BufferedMetricsLogger(opts) {
     this.aggregator = opts.aggregator || new Aggregator(opts.defaultTags);
-    this.reporter = opts.reporter || new DataDogReporter(opts.apiKey, opts.appKey, opts.agent);
+    this.reporter = opts.reporter || new DataDogReporter(opts.apiKey, opts.appKey, opts.agent, opts.apiHost);
     this.host = opts.host;
     this.prefix = opts.prefix || '';
     this.flushIntervalSeconds = opts.flushIntervalSeconds;
+    this.intervalHandler = opts.intervalHandler || function(callback, delay) {
+        return setTimeout(callback, delay);
+    };
 
     if (this.flushIntervalSeconds) {
         debug('Auto-flushing every %d seconds', this.flushIntervalSeconds);
@@ -54,9 +59,13 @@ function BufferedMetricsLogger(opts) {
         self.flush();
         if (self.flushIntervalSeconds) {
             var interval = self.flushIntervalSeconds * 1000;
-            var tid = setTimeout(autoFlushCallback, interval);
-            // Let the event loop exit if this is the only active timer.
-            tid.unref();
+            var tid = self.intervalHandler(autoFlushCallback, interval);
+            // `.unref()` is not available on browser `setTimeout()`
+            if (typeof tid.unref === 'function') {
+                // Node provides `.unref()` to let the event loop exit
+                // if this is the only active timer left.
+                tid.unref();
+            }
         }
     };
 

lib/reporters.js

@@ -13,24 +13,26 @@ function NullReporter(apiKey, appKey) {
 
 NullReporter.prototype.report = function(series, onSuccess, onError) {
     // Do nothing.
-    onSuccess();
+    if (typeof onSuccess === 'function') {
+        onSuccess();
+    }
 };
 
 
 //
 // DataDogReporter
 //
-
-function DataDogReporter(apiKey, appKey, agent) {
+function DataDogReporter(apiKey, appKey, agent, apiHost) {
     apiKey = apiKey || process.env.DATADOG_API_KEY;
     appKey = appKey || process.env.DATADOG_APP_KEY;
+    apiHost = apiHost || process.env.DATADOG_API_HOST || 'api.datadoghq.com';
 
     if (!apiKey) {
         throw new Error('DATADOG_API_KEY environment variable not set');
     }
 
     // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
-    dogapi.initialize({api_key: apiKey, app_key: appKey, proxy_agent: agent });
+    dogapi.initialize({ api_key: apiKey, app_key: appKey, api_host: apiHost, proxy_agent: agent });
     // jscs:enable requireCamelCaseOrUpperCaseIdentifiers
 }