Expose startNetLog / stopNetLog from HttpUrlRequestFactory.

components/cronet/android/java/src/org/chromium/net/HttpUrlRequestFactory.java

 // Copyright 2014 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.net;
 
 import android.content.Context;
 import android.util.Log;
 
 import java.lang.reflect.Constructor;
@@ skipping 41 matching lines @@
             int requestPriority, Map<String, String> headers,
             HttpUrlRequestListener listener);
 
     /**
      * Creates a new request intended for streaming.
      */
     public abstract HttpUrlRequest createRequest(String url,
             int requestPriority, Map<String, String> headers,
             WritableByteChannel channel, HttpUrlRequestListener listener);
 
+    /**
+     * Starts NetLog logging to a file named |fileName| in the
+     * application temporary directory. |fileName| must not be empty. Log level
+     * is LOG_ALL_BUT_BYTES. If the file exists it is truncated before starting.

[mmenke, 2014/09/29 18:53:19]

If we're going to document the log level, we should explicitly set it as well
(I'm changing the default level of the NetLogLogger in another CL to hide
cookies and the like, and am thinking I won't update users of the NetLogLogger,
on the assumption if they don't set it, they're fine with the default value).

[mef, 2014/09/29 21:21:24]

I'm fine with not documenting the log level, although we should mention that it
may contain some PII.

[mmenke, 2014/09/29 21:24:30]

Great, let's do that for now, then.

I wonder if it's better to include the cookies by default or not - admittedly,
we don't even have an on-disk cookie store hooked up yet, but worth thinking
about the typical use case, or if we should just expose the option to the
embedder.

[mef, 2014/09/29 22:25:09]

Done.

+     * If actively logging the call is ignored.
+     */
+    public abstract void startNetLogToFile(String fileName);
+
+    /**
+     * Stops NetLog logging and flushes file to disk. If a logging session is
+     * not in progress this call is ignored.
+     */
+    public abstract void stopNetLog();
+
     private static HttpUrlRequestFactory createChromiumFactory(
             Context context, HttpUrlRequestFactoryConfig config) {
         HttpUrlRequestFactory factory = null;
         try {
             Class<? extends HttpUrlRequestFactory> factoryClass =
                     HttpUrlRequestFactory.class.getClassLoader().
                             loadClass(CHROMIUM_URL_REQUEST_FACTORY).
                             asSubclass(HttpUrlRequestFactory.class);
             Constructor<? extends HttpUrlRequestFactory> constructor =
                     factoryClass.getConstructor(
                             Context.class, HttpUrlRequestFactoryConfig.class);
             HttpUrlRequestFactory chromiumFactory =
                     constructor.newInstance(context, config);
             if (chromiumFactory.isEnabled()) {
                 factory = chromiumFactory;
             }
         } catch (ClassNotFoundException e) {
             // Leave as null
         } catch (Exception e) {
             throw new IllegalStateException(
                     "Cannot instantiate: " +
                     CHROMIUM_URL_REQUEST_FACTORY,
                     e);
         }
         return factory;
     }
 }