Upload some changes for gauge manager changes

Author: tejasd

firebase-perf/src/main/java/com/google/firebase/perf/FirebasePerformance.java

@@ -37,14 +37,14 @@
 import com.google.firebase.perf.metrics.HttpMetric;
 import com.google.firebase.perf.metrics.Trace;
 import com.google.firebase.perf.session.FirebasePerformanceSessionSubscriber;
-import com.google.firebase.sessions.api.SessionSubscriber;
 import com.google.firebase.perf.session.SessionManager;
 import com.google.firebase.perf.transport.TransportManager;
 import com.google.firebase.perf.util.Constants;
 import com.google.firebase.perf.util.ImmutableBundle;
 import com.google.firebase.perf.util.Timer;
 import com.google.firebase.remoteconfig.RemoteConfigComponent;
 import com.google.firebase.sessions.api.FirebaseSessionsDependencies;
+import com.google.firebase.sessions.api.SessionSubscriber;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.net.URL;
@@ -187,7 +187,8 @@ public static FirebasePerformance getInstance() {
     sessionManager.setApplicationContext(appContext);
 
     mPerformanceCollectionForceEnabledState = configResolver.getIsPerformanceCollectionEnabled();
-    this.sessionSubscriber = new FirebasePerformanceSessionSubscriber(isPerformanceCollectionEnabled());
+    this.sessionSubscriber =
+        new FirebasePerformanceSessionSubscriber(isPerformanceCollectionEnabled());
     FirebaseSessionsDependencies.register(this.sessionSubscriber);
 
     if (logger.isLogcatEnabled() && isPerformanceCollectionEnabled()) {

firebase-perf/src/main/java/com/google/firebase/perf/session/SessionManager.java

@@ -19,6 +19,7 @@
 import androidx.annotation.Keep;
 import androidx.annotation.VisibleForTesting;
 import com.google.firebase.perf.application.AppStateMonitor;
+import com.google.firebase.perf.application.AppStateUpdateHandler;
 import com.google.firebase.perf.session.gauges.GaugeManager;
 import com.google.firebase.perf.v1.ApplicationProcessState;
 import com.google.firebase.perf.v1.GaugeMetadata;
@@ -32,7 +33,7 @@
 
 /** Session manager to generate sessionIDs and broadcast to the application. */
 @Keep // Needed because of b/117526359.
-public class SessionManager {
+public class SessionManager extends AppStateUpdateHandler {
 
   @SuppressLint("StaticFieldLeak")
   private static final SessionManager instance = new SessionManager();
@@ -69,6 +70,18 @@ public SessionManager(
     this.appStateMonitor = appStateMonitor;
   }
 
+  @Override
+  public void onUpdateAppState(ApplicationProcessState newAppState) {
+    super.onUpdateAppState(newAppState);
+    if (appStateMonitor.isColdStart()) {
+      // We want the Session to remain unchanged if this is a cold start of the app since we already
+      // update the PerfSession in FirebasePerfProvider#onAttachInfo().
+      return;
+    }
+
+    updateGaugeCollection(newAppState);
+  }
+
   /**
    * Finalizes gauge initialization during cold start. This must be called before app start finishes
    * (currently that is before onResume finishes) to ensure gauge collection starts on time.
@@ -118,7 +131,8 @@ public void updatePerfSession(PerfSession perfSession) {
     }
 
     // Start of stop the gauge data collection.
-    startOrStopCollectingGauges(appStateMonitor.getAppState());
+    startOrStopCollectingGauges();
+    updateGaugeCollection(appStateMonitor.getAppState());
   }
 
   /**
@@ -128,7 +142,7 @@ public void updatePerfSession(PerfSession perfSession) {
    * this does not reset the perfSession.
    */
   public void initializeGaugeCollection() {
-    startOrStopCollectingGauges(ApplicationProcessState.FOREGROUND);
+    startOrStopCollectingGauges();
   }
 
   /**
@@ -155,14 +169,18 @@ public void unregisterForSessionUpdates(WeakReference<SessionAwareObject> client
     }
   }
 
-  private void startOrStopCollectingGauges(ApplicationProcessState appState) {
+  private void startOrStopCollectingGauges() {
     if (perfSession.isGaugeAndEventCollectionEnabled()) {
-      gaugeManager.startCollectingGauges(perfSession, appState);
+      gaugeManager.startCollectingGauges(perfSession);
     } else {
       gaugeManager.stopCollectingGauges();
     }
   }
 
+  private void updateGaugeCollection(ApplicationProcessState applicationProcessState) {
+    gaugeManager.updateGaugeCollection(applicationProcessState);
+  }
+
   @VisibleForTesting
   public void setPerfSession(PerfSession perfSession) {
     this.perfSession = perfSession;

firebase-perf/src/main/java/com/google/firebase/perf/session/gauges/GaugeManager.java

@@ -60,10 +60,11 @@ public class GaugeManager {
 
   @Nullable private GaugeMetadataManager gaugeMetadataManager;
   @Nullable private ScheduledFuture<?> gaugeManagerDataCollectionJob = null;
-  @Nullable private String sessionId = null;
-  @Nullable private String aqsSessionId = null;
-  private ApplicationProcessState applicationProcessState =
-      ApplicationProcessState.APPLICATION_PROCESS_STATE_UNKNOWN;
+  @Nullable private PerfSession session = null;
+
+  // The default value for application process state is Foreground. This will be updated based on
+  // app state changes.
+  private ApplicationProcessState applicationProcessState = ApplicationProcessState.FOREGROUND;
 
   // TODO(b/258263016): Migrate to go/firebase-android-executors
   @SuppressLint("ThreadPoolCreation")
@@ -104,48 +105,34 @@ public static synchronized GaugeManager getInstance() {
     return instance;
   }
 
-  /**
-   * Starts the collection of available gauges for the given {@code sessionId} and {@code
-   * applicationProcessState}. The collected Gauge Metrics will be flushed at regular intervals.
-   *
-   * <p>GaugeManager can only collect gauges for one session at a time, and if this method is called
-   * again with the same or new sessionId while it's already collecting gauges, all future gauges
-   * will then be associated with the same or new sessionId and applicationProcessState.
-   *
-   * @param session The {@link PerfSession} to which the collected gauges will be associated with.
-   * @param applicationProcessState The {@link ApplicationProcessState} the collected GaugeMetrics
-   *     will be associated with.
-   * @note: This method is NOT thread safe - {@link this.startCollectingGauges()} and {@link
-   *     this.stopCollectingGauges()} should always be called from the same thread.
-   */
-  public void startCollectingGauges(
-      PerfSession session, ApplicationProcessState applicationProcessState) {
-    if (this.sessionId != null) {
-      stopCollectingGauges();
+  public void updateGaugeCollection(ApplicationProcessState applicationProcessState) {
+    if (gaugeManagerDataCollectionJob != null) {
+      gaugeManagerDataCollectionJob.cancel(false);
     }
 
-    long collectionFrequency = startCollectingGauges(applicationProcessState, session.getTimer());
-    if (collectionFrequency == INVALID_GAUGE_COLLECTION_FREQUENCY) {
-      logger.warn("Invalid gauge collection frequency. Unable to start collecting Gauges.");
+    if (session == null || !session.isGaugeAndEventCollectionEnabled()) {
+      logger.warn("Not starting gauge collection.");
+      stopCollectingGauges();
       return;
     }
 
-    this.sessionId = session.sessionId();
-    this.aqsSessionId = session.aqsSessionId();
-    this.applicationProcessState = applicationProcessState;
+    if (session.aqsSessionId() == null) {
+      logger.warn("Not starting gauge collection.");
+    }
 
-    // This is needed, otherwise the Runnable might use a stale value.
-    final String sessionIdForScheduledTask = aqsSessionId;
-    final ApplicationProcessState applicationProcessStateForScheduledTask = applicationProcessState;
+    long collectionFrequency =
+        Math.min(
+            getCpuGaugeCollectionFrequencyMs(applicationProcessState),
+            getMemoryGaugeCollectionFrequencyMs(applicationProcessState));
+    String sessionIdForScheduledTask = session.aqsSessionId();
 
-    // TODO(b/394127311): Switch to using AQS.
     try {
       gaugeManagerDataCollectionJob =
           gaugeManagerExecutor
               .get()
               .scheduleWithFixedDelay(
                   () -> {
-                    syncFlush(sessionIdForScheduledTask, applicationProcessStateForScheduledTask);
+                    syncFlush(sessionIdForScheduledTask, applicationProcessState);
                   },
                   /* initialDelay= */ collectionFrequency
                       * APPROX_NUMBER_OF_DATA_POINTS_PER_GAUGE_METRIC,
@@ -155,6 +142,36 @@ public void startCollectingGauges(
     } catch (RejectedExecutionException e) {
       logger.warn("Unable to start collecting Gauges: " + e.getMessage());
     }
+
+    if (this.applicationProcessState != applicationProcessState) {
+      this.applicationProcessState = applicationProcessState;
+
+      // If there's a change in App State - update the gauge collection frequency as well.
+      stopCollectingGauges();
+      startCollectingGauges(applicationProcessState, this.session.getTimer());
+    }
+  }
+
+  /**
+   * Starts the collection of available gauges for the given {@code session}.
+   *
+   * <p>GaugeManager can only collect gauges for one session at a time, and if this method is called
+   * again with the same or new sessionId while it's already collecting gauges, all future gauges
+   * will then be associated with the same or new sessionId and applicationProcessState.
+   *
+   * @param session The {@link PerfSession} to which the collected gauges will be associated with.
+   * @note: This method is NOT thread safe - {@link this.startCollectingGauges()} and {@link
+   *     this.stopCollectingGauges()} should always be called from the same thread.
+   */
+  public void startCollectingGauges(PerfSession session) {
+    if (this.session != null) {
+      stopCollectingGauges();
+    }
+
+    long collectionFrequency = startCollectingGauges(applicationProcessState, session.getTimer());
+    if (collectionFrequency == INVALID_GAUGE_COLLECTION_FREQUENCY) {
+      logger.warn("Invalid gauge collection frequency. Unable to start collecting Gauges.");
+    }
   }
 
   /**
@@ -192,12 +209,14 @@ private long startCollectingGauges(ApplicationProcessState appState, Timer refer
    *     this.stopCollectingGauges()} should always be called from the same thread.
    */
   public void stopCollectingGauges() {
-    if (this.sessionId == null) {
+    if (this.session == null) {
       return;
     }
 
     // This is needed, otherwise the Runnable might use a stale value.
-    final String sessionIdForScheduledTask = aqsSessionId;
+
+    // AQS is guaranteed to be available when stopping gauge collection.
+    final String sessionIdForScheduledTask = session.aqsSessionId();
     final ApplicationProcessState applicationProcessStateForScheduledTask = applicationProcessState;
 
     cpuGaugeCollector.get().stopCollecting();
@@ -207,7 +226,6 @@ public void stopCollectingGauges() {
       gaugeManagerDataCollectionJob.cancel(false);
     }
 
-    // TODO(b/394127311): Switch to using AQS.
     // Flush any data that was collected for this session one last time.
     @SuppressWarnings("FutureReturnValueIgnored")
     ScheduledFuture<?> unusedFuture =
@@ -220,8 +238,7 @@ public void stopCollectingGauges() {
                 TIME_TO_WAIT_BEFORE_FLUSHING_GAUGES_QUEUE_MS,
                 TimeUnit.MILLISECONDS);
 
-    this.sessionId = null;
-    this.applicationProcessState = ApplicationProcessState.APPLICATION_PROCESS_STATE_UNKNOWN;
+    this.session = null;
   }
 
   /**
@@ -407,4 +424,9 @@ private long getMemoryGaugeCollectionFrequencyMs(
       return memoryGaugeCollectionFrequency;
     }
   }
+
+  @VisibleForTesting
+  void setApplicationProcessState(ApplicationProcessState applicationProcessState) {
+    this.applicationProcessState = applicationProcessState;
+  }
 }

firebase-perf/src/test/java/com/google/firebase/perf/session/SessionManagerTest.java

@@ -144,8 +144,8 @@ public void testUpdatePerfSessionStartsCollectingGaugesIfSessionIsVerbose() {
     testSessionManager.setApplicationContext(mockApplicationContext);
 
     verify(mockGaugeManager, times(1)).initializeGaugeMetadataManager(mockApplicationContext);
-    verify(mockGaugeManager, times(1))
-        .startCollectingGauges(newSession, ApplicationProcessState.FOREGROUND);
+    verify(mockGaugeManager, times(1)).startCollectingGauges(newSession);
+    verify(mockGaugeManager, times(1)).updateGaugeCollection(ApplicationProcessState.FOREGROUND);
   }
 
   @Test