WebCore/page/EventSource.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/page/EventSource.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,335 @@
+/*
+ * Copyright (C) 2009 Ericsson AB
+ * All rights reserved.
+ * Copyright (C) 2010 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name of Ericsson nor the names of its contributors
+ *    may be used to endorse or promote products derived from this
+ *    software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#if ENABLE(EVENTSOURCE)
+
+#include "EventSource.h"
+
+#include "Cache.h"
+#include "DOMWindow.h"
+#include "Event.h"
+#include "EventException.h"
+#include "PlatformString.h"
+#include "MessageEvent.h"
+#include "ResourceError.h"
+#include "ResourceRequest.h"
+#include "ResourceResponse.h"
+#include "ScriptExecutionContext.h"
+#include "SerializedScriptValue.h"
+#include "TextResourceDecoder.h"
+#include "ThreadableLoader.h"
+
+namespace WebCore {
+
+const unsigned long long EventSource::defaultReconnectDelay = 3000;
+
+inline EventSource::EventSource(const KURL& url, ScriptExecutionContext* context)
+    : ActiveDOMObject(context, this)
+    , m_url(url)
+    , m_state(CONNECTING)
+    , m_decoder(TextResourceDecoder::create("text/plain", "UTF-8"))
+    , m_reconnectTimer(this, &EventSource::reconnectTimerFired)
+    , m_discardTrailingNewline(false)
+    , m_failSilently(false)
+    , m_requestInFlight(false)
+    , m_reconnectDelay(defaultReconnectDelay)
+    , m_origin(context->securityOrigin()->toString())
+{
+}
+
+PassRefPtr<EventSource> EventSource::create(const String& url, ScriptExecutionContext* context, ExceptionCode& ec)
+{
+    if (url.isEmpty()) {
+        ec = SYNTAX_ERR;
+        return 0;
+    }
+
+    KURL fullURL = context->completeURL(url);
+    if (!fullURL.isValid()) {
+        ec = SYNTAX_ERR;
+        return 0;
+    }
+
+    // FIXME: Should support at least some cross-origin requests.
+    if (!context->securityOrigin()->canRequest(fullURL)) {
+        ec = SECURITY_ERR;
+        return 0;
+    }
+
+    RefPtr<EventSource> source = adoptRef(new EventSource(fullURL, context));
+
+    source->setPendingActivity(source.get());
+    source->connect();
+
+    return source.release();
+}
+
+EventSource::~EventSource()
+{
+}
+
+void EventSource::connect()
+{
+    ResourceRequest request(m_url);
+    request.setHTTPMethod("GET");
+    request.setHTTPHeaderField("Accept", "text/event-stream");
+    request.setHTTPHeaderField("Cache-Control", "no-cache");
+    if (!m_lastEventId.isEmpty())
+        request.setHTTPHeaderField("Last-Event-ID", m_lastEventId);
+
+    ThreadableLoaderOptions options;
+    options.sendLoadCallbacks = true;
+    options.sniffContent = false;
+    options.allowCredentials = true;
+
+    m_loader = ThreadableLoader::create(scriptExecutionContext(), this, request, options);
+
+    m_requestInFlight = true;
+
+    if (!scriptExecutionContext()->isWorkerContext())
+        cache()->loader()->nonCacheRequestInFlight(m_url);
+}
+
+void EventSource::endRequest()
+{
+    m_requestInFlight = false;
+
+    if (!m_failSilently)
+        dispatchEvent(Event::create(eventNames().errorEvent, false, false));
+
+    if (!scriptExecutionContext()->isWorkerContext())
+        cache()->loader()->nonCacheRequestComplete(m_url);
+
+    if (m_state != CLOSED)
+        scheduleReconnect();
+    else
+        unsetPendingActivity(this);
+}
+
+void EventSource::scheduleReconnect()
+{
+    m_state = CONNECTING;
+    m_reconnectTimer.startOneShot(m_reconnectDelay / 1000);
+}
+
+void EventSource::reconnectTimerFired(Timer<EventSource>*)
+{
+    connect();
+}
+
+String EventSource::url() const
+{
+    return m_url.string();
+}
+
+EventSource::State EventSource::readyState() const
+{
+    return m_state;
+}
+
+void EventSource::close()
+{
+    if (m_state == CLOSED)
+        return;
+
+    if (m_reconnectTimer.isActive()) {
+        m_reconnectTimer.stop();
+        unsetPendingActivity(this);
+    }
+
+    m_state = CLOSED;
+    m_failSilently = true;
+
+    if (m_requestInFlight)
+        m_loader->cancel();
+}
+
+ScriptExecutionContext* EventSource::scriptExecutionContext() const
+{
+    return ActiveDOMObject::scriptExecutionContext();
+}
+
+void EventSource::didReceiveResponse(const ResourceResponse& response)
+{
+    int statusCode = response.httpStatusCode();
+    if (statusCode == 200 && response.httpHeaderField("Content-Type") == "text/event-stream") {
+        m_state = OPEN;
+        dispatchEvent(Event::create(eventNames().openEvent, false, false));
+    } else {
+        if (statusCode <= 200 || statusCode > 299)
+            m_state = CLOSED;
+        m_loader->cancel();
+    }
+}
+
+void EventSource::didReceiveData(const char* data, int length)
+{
+    append(m_receiveBuf, m_decoder->decode(data, length));
+    parseEventStream();
+}
+
+void EventSource::didFinishLoading(unsigned long)
+{
+    if (m_receiveBuf.size() > 0 || m_data.size() > 0) {
+        append(m_receiveBuf, "\n\n");
+        parseEventStream();
+    }
+    m_state = CONNECTING;
+    endRequest();
+}
+
+void EventSource::didFail(const ResourceError& error)
+{
+    int canceled = error.isCancellation();
+    if (((m_state == CONNECTING) && !canceled) || ((m_state == OPEN) && canceled))
+        m_state = CLOSED;
+    endRequest();
+}
+
+void EventSource::didFailRedirectCheck()
+{
+    m_state = CLOSED;
+    m_loader->cancel();
+}
+
+void EventSource::parseEventStream()
+{
+    unsigned int bufPos = 0;
+    unsigned int bufSize = m_receiveBuf.size();
+    while (bufPos < bufSize) {
+        if (m_discardTrailingNewline) {
+            if (m_receiveBuf[bufPos] == '\n')
+                bufPos++;
+            m_discardTrailingNewline = false;
+        }
+
+        int lineLength = -1;
+        int fieldLength = -1;
+        for (unsigned int i = bufPos; lineLength < 0 && i < bufSize; i++) {
+            switch (m_receiveBuf[i]) {
+            case ':':
+                if (fieldLength < 0)
+                    fieldLength = i - bufPos;
+                break;
+            case '\r':
+                m_discardTrailingNewline = true;
+            case '\n':
+                lineLength = i - bufPos;
+                break;
+            }
+        }
+
+        if (lineLength < 0)
+            break;
+
+        parseEventStreamLine(bufPos, fieldLength, lineLength);
+        bufPos += lineLength + 1;
+    }
+
+    if (bufPos == bufSize)
+        m_receiveBuf.clear();
+    else if (bufPos)
+        m_receiveBuf.remove(0, bufPos);
+}
+
+void EventSource::parseEventStreamLine(unsigned int bufPos, int fieldLength, int lineLength)
+{
+    if (!lineLength) {
+        if (!m_data.isEmpty()) {
+            m_data.removeLast();
+            dispatchEvent(createMessageEvent());
+        }
+        if (!m_eventName.isEmpty())
+            m_eventName = "";
+    } else if (fieldLength) {
+        bool noValue = fieldLength < 0;
+
+        String field(&m_receiveBuf[bufPos], noValue ? lineLength : fieldLength);
+        int step;
+        if (noValue)
+            step = lineLength;
+        else if (m_receiveBuf[bufPos + fieldLength + 1] != ' ')
+            step = fieldLength + 1;
+        else
+            step = fieldLength + 2;
+        bufPos += step;
+        int valueLength = lineLength - step;
+
+        if (field == "data") {
+            if (valueLength)
+                m_data.append(&m_receiveBuf[bufPos], valueLength);
+            m_data.append('\n');
+        } else if (field == "event")
+            m_eventName = valueLength ? String(&m_receiveBuf[bufPos], valueLength) : "";
+        else if (field == "id")
+            m_lastEventId = valueLength ? String(&m_receiveBuf[bufPos], valueLength) : "";
+        else if (field == "retry") {
+            if (!valueLength)
+                m_reconnectDelay = defaultReconnectDelay;
+            else {
+                String value(&m_receiveBuf[bufPos], valueLength);
+                bool ok;
+                unsigned long long retry = value.toUInt64(&ok);
+                if (ok)
+                    m_reconnectDelay = retry;
+            }
+        }
+    }
+}
+
+void EventSource::stop()
+{
+    close();
+}
+
+PassRefPtr<MessageEvent> EventSource::createMessageEvent()
+{
+    RefPtr<MessageEvent> event = MessageEvent::create();
+    event->initMessageEvent(m_eventName.isEmpty() ? eventNames().messageEvent : AtomicString(m_eventName), false, false, SerializedScriptValue::create(String::adopt(m_data)), m_origin, m_lastEventId, 0, 0);
+    return event.release();
+}
+
+EventTargetData* EventSource::eventTargetData()
+{
+    return &m_eventTargetData;
+}
+
+EventTargetData* EventSource::ensureEventTargetData()
+{
+    return &m_eventTargetData;
+}
+
+} // namespace WebCore
+
+#endif // ENABLE(EVENTSOURCE)