[PresentationAPI] Plumbing send(Blob) from PresentationSession IDL to platform/.

Source/modules/presentation/PresentationSession.cpp

Index: Source/modules/presentation/PresentationSession.cpp
diff --git a/Source/modules/presentation/PresentationSession.cpp b/Source/modules/presentation/PresentationSession.cpp
index 6c6e9380d43916753372d614e9046f7806214c83..11990926b21c62cb47a0e00fcda6ef6a662f0840 100644
--- a/Source/modules/presentation/PresentationSession.cpp
+++ b/Source/modules/presentation/PresentationSession.cpp
@@ -11,6 +11,8 @@
 #include "core/dom/ExceptionCode.h"
 #include "core/events/Event.h"
 #include "core/events/MessageEvent.h"
+#include "core/fileapi/FileReaderLoader.h"
+#include "core/fileapi/FileReaderLoaderClient.h"
 #include "core/frame/LocalFrame.h"
 #include "modules/EventTargetModules.h"
 #include "modules/presentation/Presentation.h"
@@ -47,6 +49,43 @@ void throwPresentationDisconnectedError(ExceptionState& exceptionState)
 
 } // namespace
 
+class PresentationSession::BlobLoader final : public GarbageCollectedFinalized<PresentationSession::BlobLoader>, public FileReaderLoaderClient {
+public:
+    BlobLoader(PassRefPtr<BlobDataHandle> blobDataHandle, PresentationSession* presentationSession)
+        : m_presentationSession(presentationSession)
+        , m_loader(FileReaderLoader::ReadAsArrayBuffer, this)
+    {
+        m_loader.start(m_presentationSession->executionContext(), blobDataHandle);
+    }
+    ~BlobLoader() override { }
+
+    // FileReaderLoaderClient functions.
+    void didStartLoading() override { }
+    void didReceiveData() override { }
+    void didFinishLoading() override
+    {
+        m_presentationSession->didFinishLoadingBlob(m_loader.arrayBufferResult());
+    }
+    void didFail(FileError::ErrorCode errorCode) override
+    {
+        m_presentationSession->didFailLoadingBlob(errorCode);
+    }
+
+    void cancel()
+    {
+        m_loader.cancel();
+    }
+
+    DEFINE_INLINE_TRACE()
+    {
+        visitor->trace(m_presentationSession);
+    }
+
+private:
+    Member<PresentationSession> m_presentationSession;
+    FileReaderLoader m_loader;
+};
+
 PresentationSession::PresentationSession(LocalFrame* frame, const String& id, const String& url)
     : DOMWindowProperty(frame)
     , m_id(id)
@@ -57,6 +96,7 @@ PresentationSession::PresentationSession(LocalFrame* frame, const String& id, co
 
 PresentationSession::~PresentationSession()
 {
+    ASSERT(!m_blobLoader);
 }
 
 // static
@@ -90,6 +130,7 @@ ExecutionContext* PresentationSession::executionContext() const
 
 DEFINE_TRACE(PresentationSession)
 {
+    visitor->trace(m_blobLoader);
     RefCountedGarbageCollectedEventTargetWithInlineData<PresentationSession>::trace(visitor);
     DOMWindowProperty::trace(visitor);
 }
@@ -136,6 +177,28 @@ void PresentationSession::sendInternal(const uint8_t* data, size_t size, Excepti
         controller->send(m_url, m_id, data, size);
 }
 
+void PresentationSession::send(Blob* data, ExceptionState& exceptionState)
+{
+    ASSERT(data);
+    if (m_state == WebPresentationSessionState::Disconnected) {
+        throwPresentationDisconnectedError(exceptionState);
+        return;
+    }
+
+    m_messages.append(adoptPtr(new Message(data->blobDataHandle())));
+    handleMessageQueue();
+}
+
+void PresentationSession::handleMessageQueue()
+{
+    if (m_messages.isEmpty() || m_blobLoader)
+        return;
+
+    Message* message = m_messages.first().get();
+    ASSERT(!m_blobLoader);

[mark a. foltz, 2015/05/26 20:41:48]

I don't think this is necessary because of the return at L195.

[USE s.singapati at gmail.com, 2015/05/27 19:37:51]

Done.

+    m_blobLoader = new BlobLoader(message->blobDataHandle, this);
+}
+
 void PresentationSession::didReceiveTextMessage(const String& message)
 {
     dispatchEvent(MessageEvent::create(message));
@@ -148,6 +211,16 @@ void PresentationSession::close()
     PresentationController* controller = presentationController();
     if (controller)
         controller->closeSession(m_url, m_id);
+
+    // Cancel current Blob loading if any.
+    if (m_blobLoader) {
+        m_blobLoader->cancel();
+        m_blobLoader.clear();
+    }
+
+    // Clear Blob message queue.
+    Deque<OwnPtr<Message>> empty;
+    m_messages.swap(empty);
 }
 
 bool PresentationSession::matches(WebPresentationSessionClient* client) const
@@ -171,4 +244,28 @@ PresentationController* PresentationSession::presentationController()
     return PresentationController::from(*frame());
 }
 
+void PresentationSession::didFinishLoadingBlob(PassRefPtr<DOMArrayBuffer> buffer)
+{
+    ASSERT(!m_messages.isEmpty());
+    m_blobLoader.clear();
+    ASSERT(buffer && buffer->buffer());
+
+    PresentationController* controller = presentationController();
+    if (controller)
+        controller->sendBlobData(m_url, m_id, static_cast<const uint8_t*>(buffer->data()), buffer->byteLength());
+
+    m_messages.removeFirst();
+    handleMessageQueue();
+}
+
+void PresentationSession::didFailLoadingBlob(FileError::ErrorCode errorCode)
+{
+    ASSERT(!m_messages.isEmpty());
+    m_blobLoader.clear();
+    // FIXME: generate error message?

[mark a. foltz, 2015/05/26 20:41:48]

There's currently no clean way to signal to the page that message sending
failed.  We could just close the session, but I would rather come up with an API
for signaling errors (i.e., PresentationSession.onerror).  Anton, WDYT?

+    // Ignore the current failed blob item and continue with next items.
+    m_messages.removeFirst();
+    handleMessageQueue();
+}
+
 } // namespace blink