Implementation of AutomationEventQueue and associated framework to support generic non-blocking aut…

chrome/browser/automation/testing_automation_provider.cc

Index: chrome/browser/automation/testing_automation_provider.cc
diff --git a/chrome/browser/automation/testing_automation_provider.cc b/chrome/browser/automation/testing_automation_provider.cc
index afc251a4d660590022094a732d548c3ad5f630a6..9c92a0040943399e1086dbbeb5c7627e3420275d 100644
--- a/chrome/browser/automation/testing_automation_provider.cc
+++ b/chrome/browser/automation/testing_automation_provider.cc
@@ -2316,6 +2316,14 @@ void TestingAutomationProvider::SendJSONRequest(int handle,
   handler_map["SetPrefs"] = &TestingAutomationProvider::SetPrefs;
   handler_map["ExecuteJavascript"] =
       &TestingAutomationProvider::ExecuteJavascriptJSON;
+  handler_map["AddDomRaisedEventObserver"] =

[Nirnimesh, 2012/03/01 10:34:12]

See corresponding comment in pyauto.py

+      &TestingAutomationProvider::AddDomRaisedEventObserver;
+  handler_map["RemoveEventObserver"] =
+      &TestingAutomationProvider::RemoveEventObserver;
+  handler_map["GetNextEvent"] =
+      &TestingAutomationProvider::GetNextEvent;
+  handler_map["ClearEventQueue"] =
+      &TestingAutomationProvider::ClearEventQueue;
   handler_map["ExecuteJavascriptInRenderView"] =
       &TestingAutomationProvider::ExecuteJavascriptInRenderView;
   handler_map["GoForward"] =
@@ -6443,6 +6451,81 @@ void TestingAutomationProvider::ExecuteJavascriptInRenderView(
                                      rvh);
 }
 
+void TestingAutomationProvider::AddDomRaisedEventObserver(

[Nirnimesh, 2012/03/01 10:34:12]

you pass a lot of other args from the python side, but you don't use them.
tab_index, windex, frame_xpath

[craigdh, 2012/03/01 21:34:18]

Those are left over from some point in the design when this function was
injecting Javascript. Fixed.

+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  if (SendErrorIfModalDialogActive(this, reply_message))
+    return;
+
+  AutomationJSONReply reply(this, reply_message);
+  std::string event_name;
+  if (!args->GetString("event_name", &event_name)) {
+    reply.SendError("'event_name' missing or invalid");
+    return;
+  }
+
+  if (!automation_event_queue_.get())
+    automation_event_queue_.reset(new AutomationEventQueue);
+
+  int observer_id = automation_event_queue_->AddObserver(
+      new DomRaisedEventObserver(automation_event_queue_.get(), event_name));
+  scoped_ptr<DictionaryValue> return_value(new DictionaryValue);
+  return_value->SetInteger("observer_id", observer_id);
+  reply.SendSuccess(return_value.get());
+}
+
+void TestingAutomationProvider::RemoveEventObserver(
+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  AutomationJSONReply reply(this, reply_message);
+  int observer_id;
+  if (!args->GetInteger("observer_id", &observer_id)) {
+    reply.SendError("'observer_id' missing or invalid");
+    return;
+  }
+  if (automation_event_queue_->RemoveObserver(observer_id)) {
+    reply.SendSuccess(NULL);
+    return;
+  }
+  if (!automation_event_queue_.get()) {

[Nirnimesh, 2012/03/01 10:34:12]

The if in line 6486 implies that this if will never succeed. Merge it with the
if in line 6482, and add a mesg like: "did you call AddDomRaisedEventObserver?"

[craigdh, 2012/03/01 21:34:18]

Done.

+    reply.SendError("No observers have been created.");
+    return;
+  }
+  reply.SendError("Invalid observer id.");
+}
+
+void TestingAutomationProvider::ClearEventQueue(
+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  AutomationJSONReply reply(this, reply_message);

[Nirnimesh, 2012/03/01 10:34:12]

remove

[craigdh, 2012/03/01 21:34:18]

Done.

+  if (automation_event_queue_.get())
+    automation_event_queue_->Clear();

[Nirnimesh, 2012/03/01 10:34:12]

Also free up automation_event_queue_?

[craigdh, 2012/03/01 21:34:18]

Changed to just automation_event_queue_.reset() which will delete the object if
it exists and the destructor will call Clear().

+  reply.SendSuccess(NULL);

[Nirnimesh, 2012/03/01 10:34:12]

AutomationJSONReply reply(this, reply_message).SendSuccess(NULL);

[craigdh, 2012/03/01 21:34:18]

Done.

+}
+
+void TestingAutomationProvider::GetNextEvent(
+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  scoped_ptr<AutomationJSONReply> reply(
+      new AutomationJSONReply(this, reply_message));
+  int observer_id;
+  bool blocking;
+  if (!args->GetInteger("observer_id", &observer_id)) {
+    reply->SendError("'observer_id' missing or invalid");
+    return;
+  }
+  if (!args->GetBoolean("blocking", &blocking)) {
+    reply->SendError("'blocking' missing or invalid");
+    return;
+  }
+  if (!automation_event_queue_.get()) {
+    reply->SendError("No observers have been created.");

[Nirnimesh, 2012/03/01 10:34:12]

Add: "Did you call AddDomRaisedEventObserver?"

[craigdh, 2012/03/01 21:34:18]

Done. Added a comment to the same effect but a little more generic so it doesn't
have to be changed when more observer types are added.

+    return;
+  }
+
+  automation_event_queue_->GetNextEvent(reply.release(), observer_id, blocking);

[Nirnimesh, 2012/03/01 10:34:12]

AutomationEventQueue::GetNextEvent takes AutomationJSONReply* as the 1st arg,
not scoped_ptr<AutomationJSONReply>.

When will reply be freed?

[craigdh, 2012/03/01 21:34:18]

When a matching event is added to the queue and the reply is used to complete
the automation call. Added a comment saying this.

+}
+
 void TestingAutomationProvider::GoForward(
     DictionaryValue* args,
     IPC::Message* reply_message) {