Bug 721020 - [New Tab Page] Add telemetry probes r=ttaubert

browser/modules/NewTabUtils.jsm

@@ -27,6 +27,9 @@ const PREF_NEWTAB_ENABLED = "browser.newtabpage.enabled";
 // The maximum number of results we want to retrieve from history.
 const HISTORY_RESULTS_LIMIT = 100;
 
+// The gather telemetry topic.
+const TOPIC_GATHER_TELEMETRY = "gather-telemetry";
+
 /**
  * Singleton that provides storage functionality.
  */
@@ -585,6 +588,47 @@ let Links = {
                                          Ci.nsISupportsWeakReference])
 };
 
+/**
+ * Singleton used to collect telemetry data.
+ *
+ */
+let Telemetry = {
+  /**
+   * Initializes object.
+   */
+  init: function Telemetry_init() {
+    Services.obs.addObserver(this, TOPIC_GATHER_TELEMETRY, false);
+  },
+
+  /**
+   * Collects data.
+   */
+  _collect: function Telemetry_collect() {
+    let probes = [
+      { histogram: "NEWTAB_PAGE_ENABLED",
+        value: AllPages.enabled },
+      { histogram: "NEWTAB_PAGE_PINNED_SITES_COUNT",
+        value: PinnedLinks.links.length },
+      { histogram: "NEWTAB_PAGE_BLOCKED_SITES_COUNT",
+        value: Object.keys(BlockedLinks.links).length }
+    ];
+
+    probes.forEach(function Telemetry_collect_forEach(aProbe) {
+      Services.telemetry.getHistogramById(aProbe.histogram)
+        .add(aProbe.value);
+    });
+  },
+
+  /**
+   * Listens for gather telemetry topic.
+   */
+  observe: function Telemetry_observe(aSubject, aTopic, aData) {
+    this._collect();
+  }
+};
+
+Telemetry.init();
+
 /**
  * Singleton that provides the public API of this JSM.
  */

toolkit/components/telemetry/TelemetryHistograms.h

@@ -434,6 +434,13 @@ HISTOGRAM_FLAG(TELEMETRY_TEST_FLAG, "a testing histogram; not meant to be touche
 HISTOGRAM_FLAG(STARTUP_CRASH_DETECTED, "Whether there was a crash during the last startup")
 HISTOGRAM_ENUMERATED_VALUES(SAFE_MODE_USAGE, 3, "Whether the user is in safe mode (No, Yes, Forced)")
 
+/**
+ * New Tab Page telemetry.
+ */
+HISTOGRAM(NEWTAB_PAGE_ENABLED, 0, 1, 2, BOOLEAN, "New tab page is enabled.")
+HISTOGRAM(NEWTAB_PAGE_PINNED_SITES_COUNT, 1, 9, 10, EXPONENTIAL, "Number of pinned sites on the new tab page.")
+HISTOGRAM(NEWTAB_PAGE_BLOCKED_SITES_COUNT, 1, 100, 10, EXPONENTIAL, "Number of sites blocked from the new tab page.")
+
 /**
  * Native Fennec Telemetry
  */