Bug 1836165 - New growth telemetry for private tab open count

app/metrics.yaml

@@ -2238,6 +2238,30 @@ metrics:
       tags:
         - Discovery
         - Search
+  private_tabs_open_count:
+    type: counter
+    lifetime: application
+    description: |
+      A counter that indicates how many PRIVATE tabs a user has open. This
+      value will only be set if the user has at least *one* open tab. If they
+      have 0, this ping will not get sent, resulting in a null value. To
+      disambiguate between a failed `private_tabs_open_count` ping and 0 open tabs,
+      please see `has_open_tabs`
+    send_in_pings:
+      - metrics
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1836165
+    data_reviews:
+      - https://github.com/mozilla-mobile/firefox-android/pull/2427
+    data_sensitivity:
+      - interaction
+    notification_emails:
+      - android-probes@mozilla.com
+      - cgordon@mozilla.com
+    expires: never
+    metadata:
+      tags:
+        - Tabs
   tabs_open_count:
     type: counter
     lifetime: application

app/src/main/java/org/mozilla/fenix/FenixApplication.kt

@@ -725,6 +725,11 @@ open class FenixApplication : LocaleAwareApplication(), Provider {
                 tabsOpenCount.add(openTabsCount)
             }
 
+            val openPrivateTabsCount = settings.openPrivateTabsCount
+            if (openPrivateTabsCount > 0) {
+                privateTabsOpenCount.add(openPrivateTabsCount)
+            }
+
             val topSitesSize = settings.topSitesSize
             hasTopSites.set(topSitesSize > 0)
             if (topSitesSize > 0) {

app/src/main/java/org/mozilla/fenix/telemetry/TelemetryMiddleware.kt

@@ -13,6 +13,7 @@ import mozilla.components.browser.state.action.TabListAction
 import mozilla.components.browser.state.selector.findTab
 import mozilla.components.browser.state.selector.findTabOrCustomTab
 import mozilla.components.browser.state.selector.normalTabs
+import mozilla.components.browser.state.selector.privateTabs
 import mozilla.components.browser.state.state.BrowserState
 import mozilla.components.browser.state.state.SessionState
 import mozilla.components.concept.base.crash.CrashReporting
@@ -94,6 +95,7 @@ class TelemetryMiddleware(
             -> {
                 // Update/Persist tabs count whenever it changes
                 settings.openTabsCount = context.state.normalTabs.count()
+                settings.openPrivateTabsCount = context.state.privateTabs.count()
                 if (context.state.normalTabs.isNotEmpty()) {
                     Metrics.hasOpenTabs.set(true)
                 } else {

app/src/main/java/org/mozilla/fenix/utils/Settings.kt

@@ -1324,6 +1324,11 @@ class Settings(private val appContext: Context) : PreferencesHolder {
         0,
     )
 
+    var openPrivateTabsCount by intPreference(
+        appContext.getPreferenceKey(R.string.pref_key_open_private_tabs_count),
+        0,
+    )
+
     var mobileBookmarksSize by intPreference(
         appContext.getPreferenceKey(R.string.pref_key_mobile_bookmarks_size),
         0,

app/src/main/res/values/preference_keys.xml

@@ -276,6 +276,7 @@
     <string name="pref_key_debug_settings" translatable="false">pref_key_debug_settings</string>
 
     <string name="pref_key_open_tabs_count" translatable="false">pref_key_open_tabs_count</string>
+    <string name="pref_key_open_private_tabs_count" translatable="false">pref_key_open_private_tabs_count</string>
 
     <!-- Add-on Metrics Values -->
     <string name="pref_key_installed_addons_count" translatable="false">pref_key_installed_addons_count</string>