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() {
+  if (fetcher_)
+    fetcher_->Cancel();
+
+  // Consumers in the browser process will not receive this message but they
+  // will be aware of the RenderFrame dying and should act on that. Consumers
+  // in the renderer process should be correctly notified.
+  ResolveCallbacks(ResolveStateFailure);
+}
+
+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) {
+  GetManifest(base::Bind(&ManifestManager::OnRequestManifestComplete,
+                         base::Unretained(this), request_id));

[Michael van Ouwerkerk, 2014/09/11 11:03:14]

Are you sure now that Unretained is the right thing to use?

[mlamouri (slow - plz ping), 2014/09/11 11:11:49]

Yes.

+}
+
+void ManifestManager::OnRequestManifestComplete(
+    int request_id, const Manifest& manifest) {
+  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;
+
+  FetchManifest();
+}
+
+void ManifestManager::DidChangeManifest() {
+  may_have_manifest_ = true;
+  manifest_dirty_ = true;
+}
+
+void ManifestManager::FetchManifest() {
+  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)));

[Michael van Ouwerkerk, 2014/09/11 11:03:14]

Also here, you checked that Unretained is the right thing to use?

[mlamouri (slow - plz ping), 2014/09/11 11:11:49]

Yes, the reason being that |fetcher_| is owned by |this| and |this| will
Cancel() the fetch in the dtor so worse case, the callback will be called at
that point. It shouldn't happen that |fetcher_| outlive |this| and runs the
callback after |this| is destroyed.

+}
+
+void ManifestManager::OnManifestFetchComplete(
+    const blink::WebURLResponse& response,
+    const std::string& data) {
+  if (response.isNull() && data.empty()) {
+    ResolveCallbacks(ResolveStateFailure);
+    return;
+  }
+
+  manifest_ = ManifestParser::Parse(data);
+
+  fetcher_.reset();
+  ResolveCallbacks(ResolveStateSuccess);
+}
+
+void ManifestManager::ResolveCallbacks(ResolveState state) {
+  if (state == ResolveStateFailure)
+    manifest_ = Manifest();
+
+  manifest_dirty_ = state != ResolveStateSuccess;
+
+  Manifest manifest = manifest_;
+  std::list<GetManifestCallback> callbacks = pending_callbacks_;
+
+  pending_callbacks_.clear();
+
+  for (std::list<GetManifestCallback>::const_iterator it = callbacks.begin();
+       it != callbacks.end(); ++it) {
+    it->Run(manifest);
+  }
+}
+
+} // namespace content