Bug 661573 - Telemetry: Do not record/send data in private mode r=Mossop

toolkit/components/telemetry/Telemetry.cpp

@@ -65,14 +65,22 @@ class TelemetryImpl : public nsITelemetry
 public:
   TelemetryImpl();
   ~TelemetryImpl();
+  
+  static bool CanRecord();
+  static already_AddRefed<nsITelemetry> CreateTelemetryInstance();
+  static void ShutdownTelemetry();
 
 private:
   // This is used for speedy JS string->Telemetry::ID conversions
   typedef nsBaseHashtableET<nsCharPtrHashKey, Telemetry::ID> CharPtrEntryType;
   typedef nsTHashtable<CharPtrEntryType> HistogramMapType;
   HistogramMapType mHistogramMap;
+  bool mCanRecord;
+  static TelemetryImpl *sTelemetry;
 };
 
+TelemetryImpl*  TelemetryImpl::sTelemetry = NULL;
+
 // A initializer to initialize histogram collection
 StatisticsRecorder gStatisticsRecorder;
 
@@ -205,12 +213,14 @@ JSHistogram_Add(JSContext *cx, uintN argc, jsval *vp)
     return JS_FALSE;
   }
 
-  JSObject *obj = JS_THIS_OBJECT(cx, vp);
-  Histogram *h = static_cast<Histogram*>(JS_GetPrivate(cx, obj));
-  if (h->histogram_type() == Histogram::BOOLEAN_HISTOGRAM)
-    h->Add(!!value);
-  else
-    h->Add(value);
+  if (TelemetryImpl::CanRecord()) {
+    JSObject *obj = JS_THIS_OBJECT(cx, vp);
+    Histogram *h = static_cast<Histogram*>(JS_GetPrivate(cx, obj));
+    if (h->histogram_type() == Histogram::BOOLEAN_HISTOGRAM)
+      h->Add(!!value);
+    else
+      h->Add(value);
+  }
   return JS_TRUE;
 }
 
@@ -246,7 +256,9 @@ WrapAndReturnHistogram(Histogram *h, JSContext *cx, jsval *ret)
           && JS_DefineFunction (cx, obj, "snapshot", JSHistogram_Snapshot, 1, 0)) ? NS_OK : NS_ERROR_FAILURE;
 }
 
-TelemetryImpl::TelemetryImpl() {
+TelemetryImpl::TelemetryImpl():
+mCanRecord(true)
+{
   mHistogramMap.Init(Telemetry::HistogramCount);
 }
 
@@ -317,16 +329,43 @@ TelemetryImpl::GetHistogramById(const nsACString &name, JSContext *cx, jsval *re
   return WrapAndReturnHistogram(h, cx, ret);
 }
 
-NS_IMPL_THREADSAFE_ISUPPORTS1(TelemetryImpl, nsITelemetry)
-
-already_AddRefed<nsITelemetry>
-CreateTelemetryInstance()
-{
-  nsCOMPtr<nsITelemetry> telemetry = new TelemetryImpl();
-  return telemetry.forget();
+NS_IMETHODIMP
+TelemetryImpl::GetCanRecord(PRBool *ret) {
+  *ret = mCanRecord;
+  return NS_OK;
 }
 
-NS_GENERIC_FACTORY_SINGLETON_CONSTRUCTOR(nsITelemetry, CreateTelemetryInstance)
+NS_IMETHODIMP
+TelemetryImpl::SetCanRecord(PRBool canRecord) {
+  mCanRecord = !!canRecord;
+  return NS_OK;
+}
+
+bool
+TelemetryImpl::CanRecord() {
+  return !sTelemetry || sTelemetry->mCanRecord;
+}
+
+already_AddRefed<nsITelemetry>
+TelemetryImpl::CreateTelemetryInstance()
+{
+  NS_ABORT_IF_FALSE(sTelemetry == NULL, "CreateTelemetryInstance may only be called once, via GetService()");
+  sTelemetry = new TelemetryImpl(); 
+  // AddRef for the local reference
+  NS_ADDREF(sTelemetry);
+  // AddRef for the caller
+  NS_ADDREF(sTelemetry);
+  return sTelemetry;
+}
+
+void
+TelemetryImpl::ShutdownTelemetry()
+{
+  NS_IF_RELEASE(sTelemetry);
+}
+
+NS_IMPL_THREADSAFE_ISUPPORTS1(TelemetryImpl, nsITelemetry)
+NS_GENERIC_FACTORY_SINGLETON_CONSTRUCTOR(nsITelemetry, TelemetryImpl::CreateTelemetryInstance)
 
 #define NS_TELEMETRY_CID \
   {0xaea477f2, 0xb3a2, 0x469c, {0xaa, 0x29, 0x0a, 0x82, 0xd1, 0x32, 0xb8, 0x29}}
@@ -349,7 +388,7 @@ const Module kTelemetryModule = {
   NULL,
   NULL,
   NULL,
-  NULL,
+  TelemetryImpl::ShutdownTelemetry
 };
 
 } // anonymous namespace
@@ -360,6 +399,9 @@ namespace Telemetry {
 void
 Accumulate(ID aHistogram, PRUint32 aSample)
 {
+  if (!TelemetryImpl::CanRecord()) {
+    return;
+  }
   Histogram *h;
   nsresult rv = GetHistogramByEnumId(aHistogram, &h);
   if (NS_SUCCEEDED(rv))

toolkit/components/telemetry/TelemetryPing.js

@@ -295,6 +295,24 @@ TelemetryPing.prototype = {
     request.send(nativeJSON.encode(payload));
   },
   
+  attachObservers: function attachObservers() {
+    if (!this._initialized)
+      return;
+    let idleService = Cc["@mozilla.org/widget/idleservice;1"].
+                      getService(Ci.nsIIdleService);
+    idleService.addIdleObserver(this, TELEMETRY_INTERVAL);
+    Services.obs.addObserver(this, "idle-daily", false);
+  },
+
+  detachObservers: function detachObservers() {
+    if (!this._initialized)
+      return;
+    let idleService = Cc["@mozilla.org/widget/idleservice;1"].
+                      getService(Ci.nsIIdleService);
+    idleService.removeIdleObserver(this, TELEMETRY_INTERVAL);
+    Services.obs.removeObserver(this, "idle-daily");
+  },
+
   /**
    * Initializes telemetry within a timer. If there is no PREF_SERVER set, don't turn on telemetry.
    */
@@ -306,17 +324,23 @@ TelemetryPing.prototype = {
     } catch (e) {
       // Prerequesite prefs aren't set
     }
-    if (!enabled) 
+    if (!enabled) {
+      // Turn off local telemetry if telemetry is disabled.
+      // This may change once about:telemetry is added.
+      Telemetry.canRecord = false;
       return;
-  
+    }
+    Services.obs.addObserver(this, "private-browsing", false);
+    Services.obs.addObserver(this, "profile-before-change", false);
+
+    // Delay full telemetry initialization to give the browser time to
+    // run various late initializers. Otherwise our gathered memory
+    // footprint and other numbers would be too optimistic.
     let self = this;
     this._timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
     let timerCallback = function() {
-      let idleService = Cc["@mozilla.org/widget/idleservice;1"].
-                        getService(Ci.nsIIdleService);
-      idleService.addIdleObserver(self, TELEMETRY_INTERVAL);
-      Services.obs.addObserver(self, "idle-daily", false);
-      Services.obs.addObserver(self, "profile-before-change", false);
+      self._initialized = true;
+      self.attachObservers();
       self.gatherMemory();
       delete self._timer
     }
@@ -327,11 +351,9 @@ TelemetryPing.prototype = {
    * Remove observers to avoid leaks
    */
   uninstall: function uninstall() {
-    let idleService = Cc["@mozilla.org/widget/idleservice;1"].
-                      getService(Ci.nsIIdleService);
-    idleService.removeIdleObserver(this, TELEMETRY_INTERVAL);
-    Services.obs.removeObserver(this, "idle-daily");
+    this.detachObservers()
     Services.obs.removeObserver(this, "profile-before-change");
+    Services.obs.removeObserver(this, "private-browsing");
   },
 
   /**
@@ -351,6 +373,14 @@ TelemetryPing.prototype = {
     case "idle":
       this.gatherMemory();
       break;
+    case "private-browsing":
+      Telemetry.canRecord = aData == "exit";
+      if (aData == "enter") {
+        this.detachObservers()
+      } else {
+        this.attachObservers()
+      }
+      break;
     case "test-ping":
       server = aData;
       // fall through

toolkit/components/telemetry/nsITelemetry.idl

@@ -87,4 +87,9 @@ interface nsITelemetry : nsISupports
    */
   [implicit_jscontext]
   jsval getHistogramById(in ACString id);
+
+  /**
+   * Set this to false to disable gathering of telemetry statistics.
+   */
+  attribute boolean canRecord;
 };

toolkit/components/telemetry/tests/unit/test_nsITelemetry.js

@@ -3,8 +3,10 @@
 
 const Cc = Components.classes;
 const Ci = Components.interfaces;
+const Cu = Components.utils;
 
 const Telemetry = Cc["@mozilla.org/base/telemetry;1"].getService(Ci.nsITelemetry);
+Cu.import("resource://gre/modules/Services.jsm");
 
 function test_histogram(histogram_type, name, min, max, bucket_count) {
   var h = Telemetry.newHistogram(name, min, max, bucket_count, histogram_type);
@@ -85,6 +87,18 @@ function test_getHistogramById() {
   do_check_eq(s.max, 10000);
 }
 
+// Check that telemetry doesn't record in private mode
+function test_privateMode() {
+  var h = Telemetry.newHistogram("test::private_mode_boolean", 1,2,3, Telemetry.HISTOGRAM_BOOLEAN);
+  var orig = h.snapshot();
+  Telemetry.canRecord = false;
+  h.add(1);
+  do_check_eq(uneval(orig), uneval(h.snapshot()));
+  Telemetry.canRecord = true;
+  h.add(1);
+  do_check_neq(uneval(orig), uneval(h.snapshot()));
+}
+
 function run_test()
 {
   let kinds = [Telemetry.HISTOGRAM_EXPONENTIAL, Telemetry.HISTOGRAM_LINEAR]
@@ -99,4 +113,5 @@ function run_test()
 
   test_boolean_histogram();
   test_getHistogramById();
+  test_privateMode();
 }