Remove dependency on dateutil in memory_inspector

This patch is part of an ongoing process to unbundle memory_inspector
and make it a chrome app. It removes the dependency of www_server.py
on the dateutil module, which is not part of the Python Standard
Library.

BUG=448399

Review URL: https://codereview.chromium.org/850033002

Cr-Commit-Position: refs/heads/master@{#311507}

2 files changed, 16 insertions, 12 deletions

diff --git a/tools/memory_inspector/memory_inspector/data/file_storage.py b/tools/memory_inspector/memory_inspector/data/file_storage.py
index 55656f5..71ccd23 100644
--- a/tools/memory_inspector/memory_inspector/data/file_storage.py
+++ b/tools/memory_inspector/memory_inspector/data/file_storage.py
@@ -108,7 +108,7 @@ class Archive(object):
 
   def StartNewSnapshot(self):
     """Creates a 2014-01-01_02:03:04.snapshot marker (an empty file)."""
-    self._cur_snapshot = Archive._TimestampToStr(datetime.datetime.now())
+    self._cur_snapshot = Archive.TimestampToStr(datetime.datetime.now())
     file_path = os.path.join(self._path,
                             self._cur_snapshot + Archive._SNAP_EXT)
     assert(not os.path.exists(file_path))
@@ -136,7 +136,7 @@ class Archive(object):
 
   def LoadMemMaps(self, timestamp):
     assert(self.HasMemMaps(timestamp))
-    snapshot_name = Archive._TimestampToStr(timestamp)
+    snapshot_name = Archive.TimestampToStr(timestamp)
     file_path = os.path.join(self._path, snapshot_name + Archive._MMAP_EXT)
     with open(file_path) as f:
       return json.load(f, cls=serialization.MmapDecoder)
@@ -154,15 +154,19 @@ class Archive(object):
 
   def LoadNativeHeap(self, timestamp):
     assert(self.HasNativeHeap(timestamp))
-    snapshot_name = Archive._TimestampToStr(timestamp)
+    snapshot_name = Archive.TimestampToStr(timestamp)
     file_path = os.path.join(self._path, snapshot_name + Archive._NHEAP_EXT)
     with open(file_path) as f:
       return json.load(f, cls=serialization.NativeHeapDecoder)
 
   def _HasSnapshotFile(self, timestamp, ext):
-    name = Archive._TimestampToStr(timestamp)
+    name = Archive.TimestampToStr(timestamp)
     return os.path.exists(os.path.join(self._path, name + ext))
 
   @staticmethod
-  def _TimestampToStr(timestamp):
-    return timestamp.strftime(Archive._TIME_FMT)
\ No newline at end of file
+  def TimestampToStr(timestamp):
+    return timestamp.strftime(Archive._TIME_FMT)
+
+  @staticmethod
+  def StrToTimestamp(timestr):
+    return datetime.datetime.strptime(timestr, Archive._TIME_FMT)
diff --git a/tools/memory_inspector/memory_inspector/frontends/www_server.py b/tools/memory_inspector/memory_inspector/frontends/www_server.py
index b5f8efc..c79112f 100644
--- a/tools/memory_inspector/memory_inspector/frontends/www_server.py
+++ b/tools/memory_inspector/memory_inspector/frontends/www_server.py
@@ -21,7 +21,6 @@ The following HTTP status code are returned by the server:
 import cgi
 import collections
 import datetime
-import dateutil.parser
 import glob
 import json
 import memory_inspector
@@ -187,7 +186,7 @@ def _CreateProfile(args, req_vars):  # pylint: disable=W0613
       return _HTTP_GONE, [], 'Cannot open archive %s' % req_vars['archive']
     first_timestamp = None
     for timestamp_str in req_vars['snapshots']:
-      timestamp = dateutil.parser.parse(timestamp_str)
+      timestamp = file_storage.Archive.StrToTimestamp(timestamp_str)
       first_timestamp = first_timestamp or timestamp
       time_delta = int((timestamp - first_timestamp).total_seconds())
       if req_vars['type'] == 'mmap':
@@ -545,7 +544,8 @@ def _ListStorage(args, req_vars):  # pylint: disable=W0613
       time_delta = '%d s.' % (timestamp - first_timestamp).total_seconds()
       resp['rows'] += [{'c': [
           {'v': archive_name, 'f': None},
-          {'v': timestamp.isoformat(), 'f': time_delta},
+          {'v': file_storage.Archive.TimestampToStr(timestamp),
+           'f': time_delta},
           {'v': archive.HasMemMaps(timestamp), 'f': None},
           {'v': archive.HasNativeHeap(timestamp), 'f': None},
       ]}]
@@ -558,7 +558,7 @@ def _LoadMmapsFromStorage(args, req_vars):  # pylint: disable=W0613
   if not archive:
     return _HTTP_GONE, [], 'Cannot open archive %s' % req_vars['archive']
 
-  timestamp = dateutil.parser.parse(args[1])
+  timestamp = file_storage.Archive.StrToTimestamp(args[1])
   if not archive.HasMemMaps(timestamp):
     return _HTTP_GONE, [], 'No mmaps for snapshot %s' % timestamp
   mmap = archive.LoadMemMaps(timestamp)
@@ -572,7 +572,7 @@ def _LoadNheapFromStorage(args, req_vars):
   if not archive:
     return _HTTP_GONE, [], 'Cannot open archive %s' % req_vars['archive']
 
-  timestamp = dateutil.parser.parse(args[1])
+  timestamp = file_storage.Archive.StrToTimestamp(args[1])
   if not archive.HasNativeHeap(timestamp):
     return _HTTP_GONE, [], 'No native heap dump for snapshot %s' % timestamp
 
@@ -758,4 +758,4 @@ def Start(http_port):
     httpd.serve_forever()
   except KeyboardInterrupt:
     pass  # Don't print useless stack traces when the user hits CTRL-C.
-  background_tasks.TerminateAll()
\ No newline at end of file
+  background_tasks.TerminateAll()