Implement ManifestManager to handle manifest in content/

content/renderer/manifest/manifest_manager.cc

+// Copyright 2014 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 "content/renderer/manifest/manifest_manager.h"
+
+#include "base/bind.h"
+#include "content/common/manifest_manager_messages.h"
+#include "content/public/renderer/render_frame.h"
+#include "content/renderer/fetchers/manifest_fetcher.h"
+#include "content/renderer/manifest/manifest_parser.h"
+#include "third_party/WebKit/public/platform/WebURLResponse.h"
+#include "third_party/WebKit/public/web/WebDocument.h"
+#include "third_party/WebKit/public/web/WebLocalFrame.h"
+
+namespace content {
+
+ManifestManager::ManifestManager(RenderFrame* render_frame)
+    : RenderFrameObserver(render_frame),
+      may_have_manifest_(false),
+      manifest_dirty_(true) {
+}
+
+ManifestManager::~ManifestManager() {
+}
+
+bool ManifestManager::OnMessageReceived(const IPC::Message& message) {
+  bool handled = true;
+
+  IPC_BEGIN_MESSAGE_MAP(ManifestManager, message)
+    IPC_MESSAGE_HANDLER(ManifestManagerMsg_RequestManifest, OnRequestManifest)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+
+  return handled;
+}
+
+void ManifestManager::OnRequestManifest(int request_id) {
+  request_ids_.push_back(request_id);

[Michael van Ouwerkerk, 2014/09/09 15:34:56]

Why store this list of ids separately? You can bind it into the callback.

[mlamouri (slow - plz ping), 2014/09/10 17:06:20]

Done.

+  GetManifest(base::Bind(&ManifestManager::OnRequestManifestComplete,
+                         base::Unretained(this)));
+}
+
+void ManifestManager::OnRequestManifestComplete(
+    const Manifest& manifest) {
+  // The ManifestManager will run the callbacks in FIFO order so the request_ids
+  // list can be used the same way.
+  // This is an implementation detail that the browser process is not aware of.
+  int request_id = request_ids_.front();
+  request_ids_.pop_front();
+
+  Send(new ManifestManagerHostMsg_RequestManifestResponse(
+      routing_id(), request_id, manifest));
+}
+
+void ManifestManager::GetManifest(const GetManifestCallback& callback) {
+  if (!may_have_manifest_) {
+    callback.Run(Manifest());
+    return;
+  }
+
+  if (!manifest_dirty_) {
+    callback.Run(manifest_);
+    return;
+  }
+
+  pending_callbacks_.push_back(callback);
+
+  // Just wait for the running call to be done if there are other callbacks.
+  if (pending_callbacks_.size() > 1)
+    return;
+
+  DownloadManifest();
+}
+
+void ManifestManager::ManifestChanged() {
+  may_have_manifest_ = true;
+  manifest_dirty_ = true;
+}
+
+void ManifestManager::DownloadManifest() {
+  GURL url(render_frame()->GetWebFrame()->document().manifestURL());
+
+  if (url.is_empty()) {
+    ResolveCallbacks(ResolveStateFailure);
+    return;
+  }
+
+  fetcher_.reset(new ManifestFetcher(url));
+
+  // TODO(mlamouri,kenneth): this is not yet taking into account manifest-src
+  // CSP rule, see http://crbug.com/409996.
+  fetcher_->Start(render_frame()->GetWebFrame(),
+                  base::Bind(&ManifestManager::OnManifestFetchComplete,
+                             base::Unretained(this)));
+}
+
+void ManifestManager::OnManifestFetchComplete(
+    const blink::WebURLResponse& response,
+    const std::string& data) {
+  if (response.isNull() && data.empty()) {
+    ResolveCallbacks(ResolveStateFailure);
+    return;
+  }
+
+  manifest_ = ManifestParser::Parse(data);
+  ResolveCallbacks(ResolveStateSuccess);
+}
+
+void ManifestManager::ResolveCallbacks(ResolveState state) {
+  if (state == ResolveStateFailure)
+    manifest_ = Manifest();
+
+  for (std::list<GetManifestCallback>::const_iterator
+       it = pending_callbacks_.begin(); it != pending_callbacks_.end(); ++it) {
+    it->Run(manifest_);
+  }
+
+  pending_callbacks_.clear();
+  manifest_dirty_ = state != ResolveStateSuccess;
+}
+
+} // namespace content