Initial implementation of ServiceWorkerGlobalScope.fetch()

Source/modules/serviceworkers/FetchManager.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 "FetchManager.h"
+
+#include "bindings/v8/ScriptPromiseResolverWithContext.h"
+#include "core/dom/DOMError.h"
+#include "core/dom/ExceptionCode.h"
+#include "core/fileapi/Blob.h"
+#include "core/loader/ThreadableLoader.h"
+#include "core/loader/ThreadableLoaderClient.h"
+#include "modules/serviceworkers/Response.h"
+#include "wtf/HashSet.h"
+
+namespace WebCore {
+
+class FetchManager::Loader : public ThreadableLoaderClient {
+public:
+    Loader(ExecutionContext*, FetchManager*, PassRefPtr<ScriptPromiseResolverWithContext>, PassOwnPtr<ResourceRequest>);
+    ~Loader();
+    virtual void didReceiveResponse(unsigned long, const ResourceResponse&);
+    virtual void didFinishLoading(unsigned long, double);
+    virtual void didFail(const ResourceError&);
+    virtual void didFailAccessControlCheck(const ResourceError&);
+    virtual void didFailRedirectCheck();
+    virtual void didDownloadData(int);
+
+    void start();
+    void cleanup();
+
+private:
+    void failed();
+    void notiyfyFinished();
+
+    ExecutionContext* m_executionContext;
+    FetchManager* m_fetchManager;
+    RefPtr<ScriptPromiseResolverWithContext> m_resolver;
+    OwnPtr<ResourceRequest> m_request;
+    RefPtr<ThreadableLoader> m_loader;
+    ResourceResponse m_response;
+    long long m_downloadedBlobLength;
+};
+
+FetchManager::Loader::Loader(ExecutionContext* executionContext, FetchManager* fetchManager, PassRefPtr<ScriptPromiseResolverWithContext> resolver, PassOwnPtr<ResourceRequest> request)
+    : m_executionContext(executionContext)
+    , m_fetchManager(fetchManager)
+    , m_resolver(resolver)
+    , m_request(request)
+    , m_downloadedBlobLength(0)
+{
+}
+
+FetchManager::Loader::~Loader()
+{
+    if (m_loader)
+        m_loader->cancel();
+}
+
+void FetchManager::Loader::didReceiveResponse(unsigned long, const ResourceResponse& response)
+{
+    m_response = response;
+}
+
+void FetchManager::Loader::didFinishLoading(unsigned long, double)
+{
+    if (!m_resolver)
+        return;
+    OwnPtr<BlobData> blobData = BlobData::create();
+    String filePath = m_response.downloadedFilePath();
+    if (!filePath.isEmpty() && m_downloadedBlobLength) {
+        blobData->appendFile(filePath);
+        // TODO(horo): Set the ContentType correctly.
+    }
+    Dictionary options;
+    // TODO(horo): fill options.
+    RefPtrWillBeRawPtr<Blob> blob = Blob::create(BlobDataHandle::create(blobData.release(), m_downloadedBlobLength));
+    // TODO(horo): Handle response status correctly.
+    m_resolver->resolve(Response::create(blob.get(), options));
+    m_resolver.clear();

[yhirano, 2014/06/10 04:57:53]

Is this clear needed?

[horo, 2014/06/10 06:20:45]

Done.

+    notiyfyFinished();
+}
+
+void FetchManager::Loader::didFail(const ResourceError& error)
+{
+    failed();
+}
+
+void FetchManager::Loader::didFailAccessControlCheck(const ResourceError& error)
+{
+    failed();
+}
+
+void FetchManager::Loader::didFailRedirectCheck()
+{
+    failed();
+}
+
+void FetchManager::Loader::didDownloadData(int dataLength)
+{
+    m_downloadedBlobLength += dataLength;
+}
+
+void FetchManager::Loader::start()
+{
+    m_request->setDownloadToFile(true);
+    ThreadableLoaderOptions options;
+    // TODO(horo): Fill options.
+    ResourceLoaderOptions resourceLoaderOptions;
+    resourceLoaderOptions.dataBufferingPolicy = DoNotBufferData;
+    // TODO(horo): Fill resourceLoaderOptions.
+    m_loader = ThreadableLoader::create(*m_executionContext, this, *m_request, options, resourceLoaderOptions);
+    if (!m_loader) {

[dominicc (has gone to gerrit), 2014/06/09 20:11:00]

No {s for single-statement bodies.

[horo, 2014/06/10 03:34:52]

Done.

+        m_resolver->reject(DOMError::create(InvalidStateError));

[yhirano, 2014/06/10 04:57:53]

DOMException?

[horo, 2014/06/10 06:20:45]

Done.

+    }
+}
+
+void FetchManager::Loader::cleanup()
+{
+    m_fetchManager = 0;
+}
+
+void FetchManager::Loader::failed()
+{
+    if (!m_resolver)
+        return;
+    m_resolver->reject(DOMError::create(NetworkError));

[yhirano, 2014/06/10 04:57:54]

DOMException

[horo, 2014/06/10 06:20:46]

Done.

+    m_resolver.clear();

[yhirano, 2014/06/10 04:57:53]

Is this statement needed?

[horo, 2014/06/10 06:20:46]

Done removed.

It was intended to avoid calling m_resolver->reject more than once.

If my understanding is correct, ThreadableLoaderClient::fail() could be called
more than once.
But FetchManager::Loader::failed() is called only once.
It is because when we call notiyfyFinished() the Loader will be deleted and
m_loader->cancel() sets ThreadableLoaderClientWrapper's m_client to 0.
So ThreadableLoaderClientWrapper::fail() don't call m_client->fail() anymore.

[yhirano, 2014/06/11 06:51:30]

It is safe to call resolve or reject more than once. From the second time, they
will be ignored.

+    notiyfyFinished();
+}
+
+void FetchManager::Loader::notiyfyFinished()
+{
+    if (m_fetchManager)
+        m_fetchManager->removeLoader(this);
+}
+
+FetchManager::FetchManager(ExecutionContext* executionContext)
+    : m_executionContext(executionContext)

[dominicc (has gone to gerrit), 2014/06/09 20:11:00]

Who manages the lifetime of the FetchManager? What happens if the
ExecutionContext dies while the FetchManager is alive/loading?

[horo, 2014/06/10 03:34:52]

I added ServiceWorkerGlobalScope::stopFetch() to stop the running fetches.

+{
+}
+
+FetchManager::~FetchManager()
+{
+    for (HashSet<OwnPtr<Loader> >::iterator it = m_loaders.begin(); it != m_loaders.end(); ++it) {
+        (*it)->cleanup();
+    }
+}
+
+ScriptPromise FetchManager::fetch(ScriptState* scriptState, PassOwnPtr<ResourceRequest> request)
+{
+    RefPtr<ScriptPromiseResolverWithContext> resolver = ScriptPromiseResolverWithContext::create(scriptState);
+    ScriptPromise promise = resolver->promise();
+
+    OwnPtr<Loader> loader(adoptPtr(new Loader(m_executionContext, this, resolver, request)));
+    Loader* tmpLoader = loader.get();

[dominicc (has gone to gerrit), 2014/06/09 20:11:00]

Maybe instead of loader/tmpLoader it is neater to call this ownLoader/loader?

[horo, 2014/06/10 03:34:52]

Done.

[yhirano, 2014/06/10 04:57:53]

You can get a pointer to the ownptr from the result of HashSet::add.

[horo, 2014/06/10 06:20:46]

Done.

+    m_loaders.add(loader.release());
+    tmpLoader->start();
+    return promise;
+}
+
+void FetchManager::removeLoader(Loader* loader)
+{
+    m_loaders.remove(loader);
+}
+
+} // namespace WebCore