Feature usage log: implement empty logger to use if statistic is disabled

platform/platform-impl/src/com/intellij/featureStatistics/FeatureUsageTrackerImpl.java

@@ -1,8 +1,8 @@
 // Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.featureStatistics;
 
+import com.intellij.internal.statistic.eventLog.FeatureUsageLogger;
 import com.intellij.internal.statistic.persistence.UsageStatisticsPersistenceComponent;
-import com.intellij.internal.statistic.eventLog.FeatureUsageEventLogger;
 import com.intellij.openapi.components.PersistentStateComponent;
 import com.intellij.openapi.components.RoamingType;
 import com.intellij.openapi.components.State;
@@ -177,7 +177,7 @@ public class FeatureUsageTrackerImpl extends FeatureUsageTracker implements Pers
      // TODO: LOG.error("Feature '" + featureId +"' must be registered prior triggerFeatureUsed() is called");
     }
     else {
-      FeatureUsageEventLogger.INSTANCE.log(descriptor.getGroupId(), descriptor.getId());
+      FeatureUsageLogger.INSTANCE.log(descriptor.getGroupId(), descriptor.getId());
       descriptor.triggerUsed();
     }
   }

platform/platform-impl/src/com/intellij/internal/statistic/UsageTrigger.java

@@ -4,11 +4,10 @@ package com.intellij.internal.statistic;
 import com.intellij.internal.statistic.beans.ConvertUsagesUtil;
 import com.intellij.internal.statistic.beans.GroupDescriptor;
 import com.intellij.internal.statistic.beans.UsageDescriptor;
+import com.intellij.internal.statistic.eventLog.FeatureUsageLogger;
 import com.intellij.internal.statistic.persistence.UsageStatisticsPersistenceComponent;
-import com.intellij.internal.statistic.eventLog.FeatureUsageEventLogger;
 import com.intellij.internal.statistic.service.fus.collectors.ApplicationUsagesCollector;
 import com.intellij.internal.statistic.service.fus.collectors.FUStatisticsDifferenceSender;
-import com.intellij.internal.statistic.service.fus.collectors.FeatureUsagesCollector;
 import com.intellij.openapi.components.*;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.xmlb.annotations.MapAnnotation;
@@ -37,7 +36,7 @@ public class UsageTrigger implements PersistentStateComponent<UsageTrigger.State
   private State myState = new State();
 
   public static void trigger(@NotNull @NonNls String feature) {
-    FeatureUsageEventLogger.INSTANCE.log("feature-usage-stats", feature);
+    FeatureUsageLogger.INSTANCE.log("feature-usage-stats", feature);
     getInstance().doTrigger(feature);
   }
 

platform/platform-impl/src/com/intellij/internal/statistic/customUsageCollectors/actions/ActionsCollectorImpl.java

@@ -6,7 +6,7 @@ import com.intellij.internal.statistic.UsagesCollector;
 import com.intellij.internal.statistic.beans.ConvertUsagesUtil;
 import com.intellij.internal.statistic.beans.GroupDescriptor;
 import com.intellij.internal.statistic.beans.UsageDescriptor;
-import com.intellij.internal.statistic.eventLog.FeatureUsageEventLogger;
+import com.intellij.internal.statistic.eventLog.FeatureUsageLogger;
 import com.intellij.internal.statistic.persistence.UsageStatisticsPersistenceComponent;
 import com.intellij.internal.statistic.service.fus.collectors.ApplicationUsagesCollector;
 import com.intellij.internal.statistic.service.fus.collectors.FUStatisticsDifferenceSender;
@@ -38,7 +38,7 @@ public class ActionsCollectorImpl extends ActionsCollector implements Persistent
     if (state == null) return;
 
     String key = ConvertUsagesUtil.escapeDescriptorName(actionId);
-    FeatureUsageEventLogger.INSTANCE.log("action-stats", key);
+    FeatureUsageLogger.INSTANCE.log("action-stats", key);
     final Integer count = state.myValues.get(key);
     int value = count == null ? 1 : count + 1;
     state.myValues.put(key, value);

platform/platform-impl/src/com/intellij/internal/statistic/eventLog/FeatureUsageFileEventLogger.kt

@@ -7,7 +7,6 @@ package com.intellij.internal.statistic.eventLog
 import com.intellij.openapi.application.ApplicationAdapter
 import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.application.PathManager
-import com.intellij.openapi.util.registry.Registry
 import org.apache.log4j.Level
 import org.apache.log4j.Logger
 import org.apache.log4j.PatternLayout
@@ -17,12 +16,12 @@ import java.io.IOException
 import java.nio.file.Paths
 import java.util.*
 
-object FeatureUsageEventLogger {
+class FeatureUsageFileEventLogger : FeatureUsageEventLogger {
   private val sessionId = UUID.randomUUID().toString().shortedUUID()
   private val bucket = "-1"
   private val recorderVersion = "1"
 
-  private val eventLogger = if (Registry.`is`("feature.usage.event.log.collect.and.upload")) createLogger() else null
+  private val eventLogger = createLogger()
 
   private var lastEvent: LogEvent? = null
   private var lastEventTime: Long = 0
@@ -31,9 +30,7 @@ object FeatureUsageEventLogger {
   init {
     ApplicationManager.getApplication().addApplicationListener(object : ApplicationAdapter() {
       override fun applicationExiting() {
-        if (eventLogger != null) {
-          dispose(eventLogger)
-        }
+        dispose(eventLogger)
       }
     })
   }
@@ -46,10 +43,8 @@ object FeatureUsageEventLogger {
     return this
   }
 
-  fun log(recorderId: String, action: String) {
-    if (eventLogger != null) {
-      log(eventLogger, LogEvent(sessionId, bucket, recorderId, recorderVersion, action))
-    }
+  override fun log(recorderId: String, action: String) {
+    log(eventLogger, LogEvent(sessionId, bucket, recorderId, recorderVersion, action))
   }
 
   private fun log(logger: Logger, event: LogEvent) {
@@ -80,7 +75,7 @@ object FeatureUsageEventLogger {
     count = 1
   }
 
-  private fun createLogger(): Logger? {
+  private fun createLogger(): Logger {
     val path = Paths.get(PathManager.getSystemPath()).resolve("event-log").resolve("feature-usage-event.log")
     val file = File(path.toUri())
 
@@ -100,4 +95,4 @@ object FeatureUsageEventLogger {
     }
     return logger
   }
-}
+}

platform/platform-impl/src/com/intellij/internal/statistic/eventLog/FeatureUsageLogger.kt

@@ -0,0 +1,25 @@
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.internal.statistic.eventLog
+
+import com.intellij.openapi.util.registry.Registry
+
+object FeatureUsageLogger {
+  private val ourLogger = if (isEnabled()) FeatureUsageFileEventLogger() else FeatureUsageEmptyEventLogger()
+
+  fun log(recorderId: String, action: String) {
+    return ourLogger.log(recorderId, action)
+  }
+
+  fun isEnabled() : Boolean {
+    return Registry.`is`("feature.usage.event.log.collect.and.upload")
+  }
+}
+
+interface FeatureUsageEventLogger {
+  fun log(recorderId: String, action: String)
+}
+
+class FeatureUsageEmptyEventLogger : FeatureUsageEventLogger {
+  override fun log(recorderId: String, action: String) {
+  }
+}