Connecting webrtc-internals WebUI frontend with the backend

chrome/browser/media/chrome_webrtc_internals.cc

+// Copyright (c) 2013 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.
+
+#include "chrome/browser/media/chrome_webrtc_internals.h"
+
+#include "chrome/browser/media/webrtc_internals_ui_observer.h"
+#include "content/public/browser/browser_thread.h"
+
+using base::DictionaryValue;
+using base::ProcessId;
+using content::BrowserThread;
+using std::string;
+
+ChromeWebRTCInternals::ChromeWebRTCInternals() {
+}
+
+ChromeWebRTCInternals::~ChromeWebRTCInternals() {
+}
+
+ChromeWebRTCInternals* ChromeWebRTCInternals::GetInstance() {
+  return Singleton<ChromeWebRTCInternals>::get();
+}
+
+void ChromeWebRTCInternals::AddPeerConnection(ProcessId pid,
+                                        int lid,
+                                        const string& url,
+                                        const string& servers,
+                                        const string& constraints) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  DictionaryValue* dict = new DictionaryValue();
+  if (!dict)
+    return;
+
+  dict->SetInteger("pid", static_cast<int>(pid));
+  dict->SetInteger("lid", lid);
+  dict->SetString("servers", servers);
+  dict->SetString("constraints", constraints);
+  dict->SetString("url", url);
+  peer_connection_data_.Append(dict);
+
+  if (observers_.size() > 0)
+    SendUpdate("addPeerConnection", dict);
+}
+
+void ChromeWebRTCInternals::RemovePeerConnection(ProcessId pid, int lid) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  for (size_t i = 0; i < peer_connection_data_.GetSize(); ++i) {
+    DictionaryValue* dict = NULL;
+    peer_connection_data_.GetDictionary(i, &dict);
+
+    int this_pid = 0;
+    int this_lid = 0;
+    dict->GetInteger("pid", &this_pid);
+    dict->GetInteger("lid", &this_lid);
+
+    if (this_pid != static_cast<int>(pid) || this_lid != lid)
+      continue;
+
+    peer_connection_data_.Remove(i, NULL);
+
+    if (observers_.size() > 0) {
+      DictionaryValue id;
+      id.SetInteger("pid", static_cast<int>(pid));
+      id.SetInteger("lid", lid);
+      SendUpdate("removePeerConnection", &id);
+    }
+    return;
+  }
+}
+
+void ChromeWebRTCInternals::AddObserver(
+      WebRTCInternalsUIObserver *observer) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  observers_.AddObserver(observer);
+}
+
+void ChromeWebRTCInternals::RemoveObserver(
+      WebRTCInternalsUIObserver *observer) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  observers_.RemoveObserver(observer);
+}
+
+void ChromeWebRTCInternals::SendUpdate(const string& command, Value* value) {
+  DCHECK(observers_.size() > 0);

[jam, 2013/01/22 17:19:12]

nit: convention is to use empty() instead of size() when check if a container is
empty or not, so

DCHECK(!observers_.empty());

+
+  FOR_EACH_OBSERVER(WebRTCInternalsUIObserver,
+                    observers_,
+                    OnUpdate(command, value));
+}