[TTS] Write initial Tap-features to Ranker.

chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchRankerLoggerImpl.java

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.contextualsearch;
 
 import org.chromium.base.Log;
 
+import java.net.URL;
+
 /**
  * Implements the UMA logging for Ranker that's used for Contextual Search Tap Suppression.
  */
 public class ContextualSearchRankerLoggerImpl implements ContextualSearchRankerLogger {
     private static final String TAG = "ContextualSearch";
 
-    @Override
-    public void log(Feature feature, Object value) {
-        // TODO(donnd): log to an actual persistent proto ASAP!
-        Log.v(TAG, "log %s with value %s", feature.toString(), value);
+    // Pointer to the native instance of this class.
+    private long mNativePointer;
+
+    // Whether logging for the current URL is currently setup.
+    private boolean mIsLoggingSetup;
+
+    // Whether the service is ready to actually record log data.
+    private boolean mCanServiceActuallyRecord;
+
+    // Whether any data has been written to the log since calling setupLoggingForPage().
+    private boolean mDidLog;
+
+    /**
+     * Constructs a Ranker Logger and associated native implementation to write Contextual Search
+     * ML data to Ranker.
+     */
+    public ContextualSearchRankerLoggerImpl() {
+        if (isEnabled()) mNativePointer = nativeInit();
+    }
+
+    /**
+     * This method should be called to clean up storage when an instance of this class is
+     * no longer in use.  The nativeDestroy will call the destructor on the native instance.
+     */
+    void destroy() {
+        if (isEnabled()) {
+            assert mNativePointer != 0;
+            writeLogAndReset();
+            nativeDestroy(mNativePointer);
+            mNativePointer = 0;
+            mCanServiceActuallyRecord = false;
+            mDidLog = false;
+        }
+        mIsLoggingSetup = false;
     }
 
     @Override
-    public void logOutcome(Object value) {
-        log(Feature.OUTCOME_WAS_PANEL_OPENED, value);
+    public void setupLoggingForPage(URL basePageUrl) {
+        mIsLoggingSetup = true;
+        if (isEnabled()) {
+            // The URL may be null for custom Chrome URIs like chrome://flags.
+            if (basePageUrl != null) {
+                nativeSetupLoggingAndRanker(mNativePointer, basePageUrl.toString());
+                mCanServiceActuallyRecord = true;
+            }
+        }
+    }
+
+    @Override
+    public void log(Feature feature, Object value) {
+        assert mIsLoggingSetup;
+        if (!isEnabled()) return;
+
+        // TODO(donnd): Add some enforcement that log() calls are done before inference time.
+        logInternal(feature, value);
+    }
+
+    @Override
+    public void logOutcome(Feature feature, Object value) {
+        assert mIsLoggingSetup;
+        if (!isEnabled()) return;
+
+        logInternal(feature, value);
     }
 
     @Override
     public void writeLogAndReset() {
-        Log.v(TAG, "Reset!\n");
+        if (isEnabled()) {
+            if (mDidLog) nativeWriteLogAndReset(mNativePointer);
+            mCanServiceActuallyRecord = false;
+            mDidLog = false;
+        }
+        mIsLoggingSetup = false;
     }
+
+    /** Whether actually writing data is enabled.  If not, we may do nothing or print. */
+    private boolean isEnabled() {
+        return ContextualSearchFieldTrial.isRankerLoggingEnabled();
+    }
+
+    /**
+     * Logs the given feature/value after checking that logging has been set up.
+     * @param feature The feature to log.
+     * @param value The value to log.
+     */
+    private void logInternal(Feature feature, Object value) {
+        if (value instanceof Boolean) {
+            logToNative(feature.toString(), ((boolean) value ? 1 : 0));
+        } else if (value instanceof Integer) {
+            logToNative(feature.toString(), Long.valueOf((int) value));
+        } else if (value instanceof Long) {
+            logToNative(feature.toString(), (long) value);
+        } else if (value instanceof Character) {
+            logToNative(feature.toString(), Character.getNumericValue((char) value));
+        } else {
+            Log.w(TAG,
+                    "Could not log feature to Ranker: " + feature.toString() + " of class "
+                            + value.getClass());
+        }
+    }
+
+    /**
+     * Logs to the native instance.  All native logging must go through this bottleneck.
+     * @param feature The feature to log.
+     * @param value The value to log.
+     */
+    private void logToNative(String feature, long value) {
+        if (mCanServiceActuallyRecord) {
+            nativeLogLong(mNativePointer, feature, value);
+            mDidLog = true;
+        }
+    }
+
+    // ============================================================================================
+    // Native methods.
+    // ============================================================================================
+    private native long nativeInit();
+    private native void nativeDestroy(long nativeContextualSearchRankerLoggerImpl);
+    private native void nativeLogLong(
+            long nativeContextualSearchRankerLoggerImpl, String featureString, long value);
+    private native void nativeSetupLoggingAndRanker(
+            long nativeContextualSearchRankerLoggerImpl, String basePageUrl);
+    private native void nativeWriteLogAndReset(long nativeContextualSearchRankerLoggerImpl);
 }