tools/android/loading: Archive tracks in LoadingTrace.

tools/android/loading/loading_trace.py

+# Copyright (c) 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.
+
+"""Represents the trace of a page load."""
+
+import page_track
+import request_track
+import tracing
+
+class LoadingTrace(object):
+  """Represents the trace of a page load."""
+  def __init__(self, url, metadata, page, request, tracing_track):
+    """Initializes a loading trace instance.
+
+    Args:
+      url: (str) URL that has been loaded
+      metadata: (dict) Metadata associated with the load.
+      page: (PageTrack) instance of PageTrack.
+      request: (RequestTrack) instance of RequestTrack.
+      tracing_track: (TracingTrack) instance of TracingTrack.
+    """
+    self.url = url
+    self.metadata = metadata
+    self.page_track = page
+    self.request_track = request
+    self.tracing_track = tracing_track
+
+  def ToJsonDict(self):
+    """Returns a dictionary representing this instance."""
+    result = {'url': self.url, 'metadata': self.metadata,

[mattcary, 2016/01/19 15:24:47]

Turn the keys into class constants to avoid typos?

[Benoit L, 2016/01/19 15:54:50]

Done.

+              'page_track': self.page_track.ToJsonDict(),
+              'request_track': self.request_track.ToJsonDict(),
+              'tracing_track': self.tracing_track.ToJsonDict()}
+    return result
+
+  @classmethod
+  def FromJsonDict(cls, json_dict):
+    """Returns an instance from a dictionary returned by ToJsonDict()."""
+    keys = ('url', 'metadata', 'page_track', 'request_track', 'tracing_track')
+    assert all(key in json_dict for key in keys)
+    page = page_track.PageTrack.FromJsonDict(json_dict['page_track'])
+    request = request_track.RequestTrack.FromJsonDict(
+        json_dict['request_track'])
+    tracing_track = tracing.TracingTrack.FromJsonDict(
+        json_dict['tracing_track'])
+    return LoadingTrace(json_dict['url'], json_dict['metadata'],
+                        page, request, tracing_track)