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..c67110add500a5bda23cec69c1ef4c25ba959d36 100644
--- a/chrome/browser/automation/testing_automation_provider.cc
+++ b/chrome/browser/automation/testing_automation_provider.cc
@@ -2316,6 +2316,16 @@ void TestingAutomationProvider::SendJSONRequest(int handle,
   handler_map["SetPrefs"] = &TestingAutomationProvider::SetPrefs;
   handler_map["ExecuteJavascript"] =
       &TestingAutomationProvider::ExecuteJavascriptJSON;
+  handler_map["AddRaisedEventObserver"] =
+      &TestingAutomationProvider::AddRaisedEventObserver;
+  handler_map["GetEvent"] =
+      &TestingAutomationProvider::GetEvent;
+  handler_map["RemoveEventObserver"] =
+      &TestingAutomationProvider::RemoveEventObserver;
+  handler_map["ClearEvents"] =
+      &TestingAutomationProvider::ClearEvents;
+  handler_map["ClearEventObservers"] =
+      &TestingAutomationProvider::ClearEventObservers;
   handler_map["ExecuteJavascriptInRenderView"] =
       &TestingAutomationProvider::ExecuteJavascriptInRenderView;
   handler_map["GoForward"] =
@@ -6443,6 +6453,72 @@ void TestingAutomationProvider::ExecuteJavascriptInRenderView(
                                      rvh);
 }
 
+void TestingAutomationProvider::AddRaisedEventObserver(
+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  if (SendErrorIfModalDialogActive(this, reply_message))
+    return;
+
+  std::string event_name;
+  if (!args->GetString("event_name", &event_name)) {
+    AutomationJSONReply(this, reply_message)
+        .SendError("'event_name' missing or invalid");
+    return;
+  }
+
+  RaisedEventObserver* jsobserver =

[Nirnimesh, 2012/02/24 23:18:09]

if the user fails to call RemoveEventObserver, does this leak?

[craigdh, 2012/02/27 22:43:38]

All un-removed observers are freed when the TestingAutomationProvider is
destroyed (for example, when the browser is restarted for each PyAuto test).
They will continue to observe and raise events until that point. I could add a
"single use" option for the use case where you only want to observe for a single
event.

+      new RaisedEventObserver(automation_event_queue_, event_name);
+  scoped_ptr<DictionaryValue> return_value(new DictionaryValue);
+  return_value->SetInteger("observer_id", jsobserver->GetId());
+  AutomationJSONReply(this, reply_message).SendSuccess(return_value.get());
+}
+
+void TestingAutomationProvider::RemoveEventObserver(

[Nirnimesh, 2012/02/24 23:18:09]

this method name does not have 'Raised'.

[craigdh, 2012/02/27 22:43:38]

It's not intended to, this method can remove any type of observer associated
with the AutomationEventQueue (ex. DomMutationEvents which are upcoming).

+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  int observer_id;
+  if (!args->GetInteger("observer_id", &observer_id)) {
+    AutomationJSONReply(this, reply_message)
+        .SendError("'observer_id' missing or invalid");
+    return;
+  }
+  automation_event_queue_.RemoveObserver(observer_id);

[Nirnimesh, 2012/02/24 23:18:09]

what if observer_id is invalid?

[craigdh, 2012/02/27 22:43:38]

Then it does not remove anything. Do you think that should be an error instead?

[Nirnimesh, 2012/02/28 09:13:09]

Yes, an error message would be nice.

+  AutomationJSONReply(this, reply_message).SendSuccess(NULL);
+}
+
+void TestingAutomationProvider::ClearEvents(

[Nirnimesh, 2012/02/24 23:18:09]

Shouldn't this imply ClearEventObservers as well?

[craigdh, 2012/02/27 22:43:38]

I was imagining cases where it may be desirable to clear all the events that
have occurred but leave the observers in place, so I separated the two
functions. It is a tradeoff though, and I don't feel strongly either way if you
think it's not worth the additional API complexity.

[Nirnimesh, 2012/02/28 09:13:09]

Unless you call ClearEventObservers as well, you can't be sure what the next
call to GetEvent() would get, since you don't know what events exactly got
deleted (an event might be raised while you're deleting, and the observer will
start processing it).

+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  automation_event_queue_.Clear();
+  AutomationJSONReply(this, reply_message).SendSuccess(NULL);
+}
+
+void TestingAutomationProvider::ClearEventObservers(
+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  automation_event_queue_.ClearObservers();
+  AutomationJSONReply(this, reply_message).SendSuccess(NULL);
+}
+
+void TestingAutomationProvider::GetEvent(
+    DictionaryValue* args,
+    IPC::Message* reply_message) {
+  int observer_id;
+  bool blocking;
+  if (!args->GetInteger("observer_id", &observer_id)) {
+    AutomationJSONReply(this, reply_message)
+        .SendError("'observer_id' missing or invalid");
+    return;
+  }
+  if (!args->GetBoolean("blocking", &blocking)) {
+    AutomationJSONReply(this, reply_message)
+        .SendError("'blocking' missing or invalid");
+    return;
+  }
+
+  automation_event_queue_.GetEvent(this, reply_message, observer_id, blocking);
+}
+
 void TestingAutomationProvider::GoForward(
     DictionaryValue* args,
     IPC::Message* reply_message) {