Smoke test for tracing infrastructure in PyAuto

chrome/test/functional/tracing/timeline_model.py

+#!/usr/bin/env python
+# Copyright (c) 2011 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.
+
+import json
+import os
+
+class TimelineModelProxy:

[nduca, 2012/07/18 05:51:35]

Seems to me you can just read the js here one-off, exeucte it, then execute the
js once during load?

+  def __init__(self, tracing_js_host, remote_object_js):
+    self._tracing_js_host = tracing_js_host
+    self._remote_object_js = remote_object_js

[nduca, 2012/07/18 05:51:35]

_remote_shim_name

+
+  def _escape_for_quoted_javascript_execution(self, js):

[nduca, 2012/07/18 05:51:35]

this should be a global var. It doesn't  need anything on self, so it should be
a member.

+    # Poor man's string escape.
+    return js.replace("'", "\\'");
+
+  # Do note that the JSON serialization process removes cyclic references.
+  # TODO(eatnumber) regenerate these cyclic references on deserialization.
+  def _js_call(self, method_name, *args):

[nduca, 2012/07/18 05:51:35]

I think this is overcomplex.

I think that you should make this be "callMethodOnThis(method_name, args).

If you need complex js that does stuff on the js side, it should be a method on
the shim that you dispatch through.

If you eventually need something specific that allows foo.bar[x].y[3], then you
should make ANOTHER method called
 _execute_in_context_of_model() that evals the provided string to get a
function, then runs the function. But, dont do that until you need it, and keep
it separate from the basic use case.

+    result = json.loads(self._tracing_js_host.ExecuteJavascriptWithFile(
+      js = """
+        // For simplicity, I'm putting a vulnerability to js injection here (in
+        // the eval), as this code should never be invoked by untrusted code.
+        // This injection allows the caller to use remote_object_jss like
+        // "profilingView.timelineView.model" which is a needed feature.
+        invokeJsMethodFromPython(eval('%s'), '%s', '%s');
+      """ % (
+        self._escape_for_quoted_javascript_execution(self._remote_object_js),
+        self._escape_for_quoted_javascript_execution(method_name),
+        self._escape_for_quoted_javascript_execution(json.dumps(args))
+      ),
+      fileName = os.path.join(os.path.dirname(__file__), 'timeline_model.js'),
+      windex = self._tracing_js_host._trace_win)

[nduca, 2012/07/18 05:51:35]

Is accessing _trace_win a normative pracice in pyauto tests? This seems pretty
wacky since _ denotes private.

+    )
+    if( result["success"] ):
+      return result["data"]
+    # TODO(eatnumber) Make these exceptions more reader friendly
+    raise Exception(result)
+
+  def getAllThreads(self):
+    return self._js_call("getAllThreads")
+
+  def getAllCpus(self):
+    return self._js_call("getAllCpus")
+
+  def getAllProcesses(self):
+    return self._js_call("getAllProcesses")
+
+  def getAllCounters(self):
+    return self._js_call("getAllCounters")
+
+  def findAllThreadsNamed(self, name):
+    return self._js_call("findAllThreadsNamed", name);
+
+# Alias TimelineModel to TimelineModelProxy for convenience
+TimelineModel = TimelineModelProxy