[NotLanded] Implement the fetching algorithm of the Web Manifest.

Source/core/loader/ManifestLoader.cpp

+// 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 "config.h"
+#include "ManifestLoader.h"
+
+#include "core/FetchInitiatorTypeNames.h"
+#include "core/dom/Document.h"
+#include "core/fetch/FetchRequest.h"
+#include "core/fetch/ResourceFetcher.h"
+#include "core/html/HTMLLinkElement.h"
+#include "core/loader/FrameLoaderClient.h"
+#include "platform/network/ResourceRequest.h"
+#include "public/platform/WebManifest.h"
+
+using namespace blink;
+
+void ManifestLoader::loadManifest(PassRefPtr<LocalFrame> frame)
+{
+    // The object will self-destruct when done.
+    ManifestLoader* manifestLoader = new ManifestLoader(frame);
+    manifestLoader->startLoading();
+}
+
+ManifestLoader::ManifestLoader(PassRefPtr<LocalFrame> frame)
+    : m_frame(frame)
+{
+    ASSERT(m_frame);
+}
+
+ManifestLoader::~ManifestLoader()
+{
+}
+
+void ManifestLoader::startLoading()
+{
+    // When deleted, |selfDestruction| will delete |this|.

[kenneth.christiansen, 2014/08/27 14:49:37]

Should be clearResource() here or when a new manifest is found?

[mlamouri (slow - plz ping), 2014/09/01 19:23:50]

Calling clearResource() is taken care of in the base class dtor.

+    OwnPtr<ManifestLoader> selfDestruction = adoptPtr(this);
+
+    FrameLoaderClient* client = m_frame->loader().client();
+    ASSERT(client);
+
+    Document* document = m_frame->document();
+    ASSERT(document);
+
+    HTMLLinkElement* linkElement = document->linkManifest();
+    if (!linkElement) {
+        client->dispatchDidFailLoadManifest(WebManifestError::NoManifest);
+        return;
+    }
+
+    KURL url(document->baseURL(), linkElement->href(), document->encoding());
+    FetchRequest request = FetchRequest(ResourceRequest(url), FetchInitiatorTypeNames::manifest);
+    AtomicString crossOriginMode = linkElement->fastGetAttribute(HTMLNames::crossoriginAttr);
+    if (!crossOriginMode.isNull())
+        request.setCrossOriginAccessControl(document->securityOrigin(), crossOriginMode);
+
+    ResourcePtr<Resource> resource = document->fetcher()->fetchManifest(request);
+    if (!resource) {
+        client->dispatchDidFailLoadManifest(WebManifestError::FetchError);
+        return;
+    }
+
+    setResource(resource);
+    // Prevent |this| from being deleted.
+    ManifestLoader* leakedManifestloader ALLOW_UNUSED = selfDestruction.leakPtr();
+}
+
+void ManifestLoader::notifyFinished(Resource* resource)
+{
+    // When deleted, |selfDestruction| will delete |this|.
+    OwnPtr<ManifestLoader> selfDestruction = adoptPtr(this);
+    ASSERT(resource == this->resource());
+
+    FrameLoaderClient* client = m_frame->loader().client();
+    ASSERT(client);
+
+    if (resource->loadFailedOrCanceled() || resource->errorOccurred()) {
+        client->dispatchDidFailLoadManifest(WebManifestError::FetchError);
+    } else {
+        // FIXME: parse the received data.
+        WebManifest manifest;

[kenneth.christiansen, 2014/08/27 14:49:37]

To make sure it actually loaded the right content we could add a json() method,
like script() method in LinkScript

[mlamouri (slow - plz ping), 2014/09/01 19:23:50]

Did you meant ScriptResource instead of LinkScript? I'm not sure who would call
that .json()? The ManifestLoader instance shouldn't be accessible. 

+        client->dispatchDidLoadManifest(manifest);
+    }
+
+    clearResource();
+}