src/third_party/WebKit/Source/core/page/EventSource.cpp

   1 /*
   2  * Copyright (C) 2009, 2012 Ericsson AB. All rights reserved.
   3  * Copyright (C) 2010 Apple Inc. All rights reserved.
   4  * Copyright (C) 2011, Code Aurora Forum. All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer
  14  *    in the documentation and/or other materials provided with the
  15  *    distribution.
  16  * 3. Neither the name of Ericsson nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this
  18  *    software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  24  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  25  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  26  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  30  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #include "config.h"
  34 #include "core/page/EventSource.h"
  35
  36 #include "bindings/core/v8/ExceptionState.h"
  37 #include "bindings/core/v8/ScriptController.h"
  38 #include "bindings/core/v8/SerializedScriptValue.h"
  39 #include "core/dom/Document.h"
  40 #include "core/dom/ExceptionCode.h"
  41 #include "core/dom/ExecutionContext.h"
  42 #include "core/events/Event.h"
  43 #include "core/events/MessageEvent.h"
  44 #include "core/frame/LocalDOMWindow.h"
  45 #include "core/frame/LocalFrame.h"
  46 #include "core/frame/csp/ContentSecurityPolicy.h"
  47 #include "core/html/parser/TextResourceDecoder.h"
  48 #include "core/inspector/ConsoleMessage.h"
  49 #include "core/loader/ThreadableLoader.h"
  50 #include "core/page/EventSourceInit.h"
  51 #include "platform/network/ResourceError.h"
  52 #include "platform/network/ResourceRequest.h"
  53 #include "platform/network/ResourceResponse.h"
  54 #include "platform/weborigin/SecurityOrigin.h"
  55 #include "public/platform/WebURLRequest.h"
  56 #include "wtf/text/StringBuilder.h"
  57
  58 namespace blink {
  59
  60 const unsigned long long EventSource::defaultReconnectDelay = 3000;
  61
  62 inline EventSource::EventSource(ExecutionContext* context, const KURL& url, const EventSourceInit& eventSourceInit)
  63     : ActiveDOMObject(context)
  64     , m_url(url)
  65     , m_withCredentials(eventSourceInit.withCredentials())
  66     , m_state(CONNECTING)
  67     , m_decoder(TextResourceDecoder::create("text/plain", "UTF-8"))
  68     , m_connectTimer(this, &EventSource::connectTimerFired)
  69     , m_discardTrailingNewline(false)
  70     , m_requestInFlight(false)
  71     , m_reconnectDelay(defaultReconnectDelay)
  72 {
  73 }
  74
  75 PassRefPtrWillBeRawPtr<EventSource> EventSource::create(ExecutionContext* context, const String& url, const EventSourceInit& eventSourceInit, ExceptionState& exceptionState)
  76 {
  77     if (url.isEmpty()) {
  78         exceptionState.throwDOMException(SyntaxError, "Cannot open an EventSource to an empty URL.");
  79         return nullptr;
  80     }
  81
  82     KURL fullURL = context->completeURL(url);
  83     if (!fullURL.isValid()) {
  84         exceptionState.throwDOMException(SyntaxError, "Cannot open an EventSource to '" + url + "'. The URL is invalid.");
  85         return nullptr;
  86     }
  87
  88     // FIXME: Convert this to check the isolated world's Content Security Policy once webkit.org/b/104520 is solved.
  89     bool shouldBypassMainWorldCSP = false;
  90     if (context->isDocument()) {
  91         Document* document = toDocument(context);
  92         shouldBypassMainWorldCSP = document->frame()->script().shouldBypassMainWorldCSP();
  93     }
  94     if (!shouldBypassMainWorldCSP && !context->contentSecurityPolicy()->allowConnectToSource(fullURL)) {
  95         // We can safely expose the URL to JavaScript, as this exception is generate synchronously before any redirects take place.
  96         exceptionState.throwSecurityError("Refused to connect to '" + fullURL.elidedString() + "' because it violates the document's Content Security Policy.");
  97         return nullptr;
  98     }
  99
 100     RefPtrWillBeRawPtr<EventSource> source = adoptRefWillBeNoop(new EventSource(context, fullURL, eventSourceInit));
 101
 102     source->scheduleInitialConnect();
 103     source->suspendIfNeeded();
 104
 105     return source.release();
 106 }
 107
 108 EventSource::~EventSource()
 109 {
 110     ASSERT(m_state == CLOSED);
 111     ASSERT(!m_requestInFlight);
 112 }
 113
 114 void EventSource::scheduleInitialConnect()
 115 {
 116     ASSERT(m_state == CONNECTING);
 117     ASSERT(!m_requestInFlight);
 118
 119     m_connectTimer.startOneShot(0, FROM_HERE);
 120 }
 121
 122 void EventSource::connect()
 123 {
 124     ASSERT(m_state == CONNECTING);
 125     ASSERT(!m_requestInFlight);
 126     ASSERT(executionContext());
 127
 128     ExecutionContext& executionContext = *this->executionContext();
 129     ResourceRequest request(m_url);
 130     request.setHTTPMethod("GET");
 131     request.setHTTPHeaderField("Accept", "text/event-stream");
 132     request.setHTTPHeaderField("Cache-Control", "no-cache");
 133     request.setRequestContext(blink::WebURLRequest::RequestContextEventSource);
 134     if (!m_lastEventId.isEmpty())
 135         request.setHTTPHeaderField("Last-Event-ID", m_lastEventId);
 136
 137     SecurityOrigin* origin = executionContext.securityOrigin();
 138
 139     ThreadableLoaderOptions options;
 140     options.preflightPolicy = PreventPreflight;
 141     options.crossOriginRequestPolicy = UseAccessControl;
 142     options.contentSecurityPolicyEnforcement = ContentSecurityPolicy::shouldBypassMainWorld(&executionContext) ? DoNotEnforceContentSecurityPolicy : EnforceConnectSrcDirective;
 143
 144     ResourceLoaderOptions resourceLoaderOptions;
 145     resourceLoaderOptions.allowCredentials = (origin->canRequest(m_url) || m_withCredentials) ? AllowStoredCredentials : DoNotAllowStoredCredentials;
 146     resourceLoaderOptions.credentialsRequested = m_withCredentials ? ClientRequestedCredentials : ClientDidNotRequestCredentials;
 147     resourceLoaderOptions.dataBufferingPolicy = DoNotBufferData;
 148     resourceLoaderOptions.securityOrigin = origin;
 149     resourceLoaderOptions.mixedContentBlockingTreatment = TreatAsActiveContent;
 150
 151     m_loader = ThreadableLoader::create(executionContext, this, request, options, resourceLoaderOptions);
 152
 153     if (m_loader)
 154         m_requestInFlight = true;
 155 }
 156
 157 void EventSource::networkRequestEnded()
 158 {
 159     if (!m_requestInFlight)
 160         return;
 161
 162     m_requestInFlight = false;
 163
 164     if (m_state != CLOSED)
 165         scheduleReconnect();
 166 }
 167
 168 void EventSource::scheduleReconnect()
 169 {
 170     m_state = CONNECTING;
 171     m_connectTimer.startOneShot(m_reconnectDelay / 1000.0, FROM_HERE);
 172     dispatchEvent(Event::create(EventTypeNames::error));
 173 }
 174
 175 void EventSource::connectTimerFired(Timer<EventSource>*)
 176 {
 177     connect();
 178 }
 179
 180 String EventSource::url() const
 181 {
 182     return m_url.string();
 183 }
 184
 185 bool EventSource::withCredentials() const
 186 {
 187     return m_withCredentials;
 188 }
 189
 190 EventSource::State EventSource::readyState() const
 191 {
 192     return m_state;
 193 }
 194
 195 void EventSource::close()
 196 {
 197     if (m_state == CLOSED) {
 198         ASSERT(!m_requestInFlight);
 199         return;
 200     }
 201
 202     // Stop trying to reconnect if EventSource was explicitly closed or if ActiveDOMObject::stop() was called.
 203     if (m_connectTimer.isActive()) {
 204         m_connectTimer.stop();
 205     }
 206
 207     if (m_requestInFlight)
 208         m_loader->cancel();
 209
 210     m_state = CLOSED;
 211 }
 212
 213 const AtomicString& EventSource::interfaceName() const
 214 {
 215     return EventTargetNames::EventSource;
 216 }
 217
 218 ExecutionContext* EventSource::executionContext() const
 219 {
 220     return ActiveDOMObject::executionContext();
 221 }
 222
 223 void EventSource::didReceiveResponse(unsigned long, const ResourceResponse& response, PassOwnPtr<WebDataConsumerHandle> handle)
 224 {
 225     ASSERT_UNUSED(handle, !handle);
 226     ASSERT(m_state == CONNECTING);
 227     ASSERT(m_requestInFlight);
 228
 229     m_eventStreamOrigin = SecurityOrigin::create(response.url())->toString();
 230     int statusCode = response.httpStatusCode();
 231     bool mimeTypeIsValid = response.mimeType() == "text/event-stream";
 232     bool responseIsValid = statusCode == 200 && mimeTypeIsValid;
 233     if (responseIsValid) {
 234         const String& charset = response.textEncodingName();
 235         // If we have a charset, the only allowed value is UTF-8 (case-insensitive).
 236         responseIsValid = charset.isEmpty() || equalIgnoringCase(charset, "UTF-8");
 237         if (!responseIsValid) {
 238             StringBuilder message;
 239             message.appendLiteral("EventSource's response has a charset (\"");
 240             message.append(charset);
 241             message.appendLiteral("\") that is not UTF-8. Aborting the connection.");
 242             // FIXME: We are missing the source line.
 243             executionContext()->addConsoleMessage(ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, message.toString()));
 244         }
 245     } else {
 246         // To keep the signal-to-noise ratio low, we only log 200-response with an invalid MIME type.
 247         if (statusCode == 200 && !mimeTypeIsValid) {
 248             StringBuilder message;
 249             message.appendLiteral("EventSource's response has a MIME type (\"");
 250             message.append(response.mimeType());
 251             message.appendLiteral("\") that is not \"text/event-stream\". Aborting the connection.");
 252             // FIXME: We are missing the source line.
 253             executionContext()->addConsoleMessage(ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, message.toString()));
 254         }
 255     }
 256
 257     if (responseIsValid) {
 258         m_state = OPEN;
 259         dispatchEvent(Event::create(EventTypeNames::open));
 260     } else {
 261         m_loader->cancel();
 262         dispatchEvent(Event::create(EventTypeNames::error));
 263     }
 264 }
 265
 266 void EventSource::didReceiveData(const char* data, unsigned length)
 267 {
 268     ASSERT(m_state == OPEN);
 269     ASSERT(m_requestInFlight);
 270
 271     append(m_receiveBuf, m_decoder->decode(data, length));
 272     parseEventStream();
 273 }
 274
 275 void EventSource::didFinishLoading(unsigned long, double)
 276 {
 277     ASSERT(m_state == OPEN);
 278     ASSERT(m_requestInFlight);
 279
 280     if (m_receiveBuf.size() > 0 || m_data.size() > 0) {
 281         parseEventStream();
 282
 283         // Discard everything that has not been dispatched by now.
 284         m_receiveBuf.clear();
 285         m_data.clear();
 286         m_eventName = emptyAtom;
 287         m_currentlyParsedEventId = nullAtom;
 288     }
 289     networkRequestEnded();
 290 }
 291
 292 void EventSource::didFail(const ResourceError& error)
 293 {
 294     ASSERT(m_state != CLOSED);
 295     ASSERT(m_requestInFlight);
 296
 297     if (error.isCancellation())
 298         m_state = CLOSED;
 299     networkRequestEnded();
 300 }
 301
 302 void EventSource::didFailAccessControlCheck(const ResourceError& error)
 303 {
 304     String message = "EventSource cannot load " + error.failingURL() + ". " + error.localizedDescription();
 305     executionContext()->addConsoleMessage(ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, message));
 306
 307     abortConnectionAttempt();
 308 }
 309
 310 void EventSource::didFailRedirectCheck()
 311 {
 312     abortConnectionAttempt();
 313 }
 314
 315 void EventSource::abortConnectionAttempt()
 316 {
 317     ASSERT(m_state == CONNECTING);
 318
 319     if (m_requestInFlight) {
 320         m_loader->cancel();
 321     } else {
 322         m_state = CLOSED;
 323     }
 324
 325     ASSERT(m_state == CLOSED);
 326     dispatchEvent(Event::create(EventTypeNames::error));
 327 }
 328
 329 void EventSource::parseEventStream()
 330 {
 331     unsigned bufPos = 0;
 332     unsigned bufSize = m_receiveBuf.size();
 333     while (bufPos < bufSize) {
 334         if (m_discardTrailingNewline) {
 335             if (m_receiveBuf[bufPos] == '\n')
 336                 bufPos++;
 337             m_discardTrailingNewline = false;
 338         }
 339
 340         int lineLength = -1;
 341         int fieldLength = -1;
 342         for (unsigned i = bufPos; lineLength < 0 && i < bufSize; i++) {
 343             switch (m_receiveBuf[i]) {
 344             case ':':
 345                 if (fieldLength < 0)
 346                     fieldLength = i - bufPos;
 347                 break;
 348             case '\r':
 349                 m_discardTrailingNewline = true;
 350             case '\n':
 351                 lineLength = i - bufPos;
 352                 break;
 353             }
 354         }
 355
 356         if (lineLength < 0)
 357             break;
 358
 359         parseEventStreamLine(bufPos, fieldLength, lineLength);
 360         bufPos += lineLength + 1;
 361
 362         // EventSource.close() might've been called by one of the message event handlers.
 363         // Per spec, no further messages should be fired after that.
 364         if (m_state == CLOSED)
 365             break;
 366     }
 367
 368     if (bufPos == bufSize)
 369         m_receiveBuf.clear();
 370     else if (bufPos)
 371         m_receiveBuf.remove(0, bufPos);
 372 }
 373
 374 void EventSource::parseEventStreamLine(unsigned bufPos, int fieldLength, int lineLength)
 375 {
 376     if (!lineLength) {
 377         if (!m_data.isEmpty()) {
 378             m_data.removeLast();
 379             if (!m_currentlyParsedEventId.isNull()) {
 380                 m_lastEventId = m_currentlyParsedEventId;
 381                 m_currentlyParsedEventId = nullAtom;
 382             }
 383             dispatchEvent(createMessageEvent());
 384         }
 385         if (!m_eventName.isEmpty())
 386             m_eventName = emptyAtom;
 387     } else if (fieldLength) {
 388         bool noValue = fieldLength < 0;
 389
 390         String field(&m_receiveBuf[bufPos], noValue ? lineLength : fieldLength);
 391         int step;
 392         if (noValue)
 393             step = lineLength;
 394         else if (m_receiveBuf[bufPos + fieldLength + 1] != ' ')
 395             step = fieldLength + 1;
 396         else
 397             step = fieldLength + 2;
 398         bufPos += step;
 399         int valueLength = lineLength - step;
 400
 401         if (field == "data") {
 402             if (valueLength)
 403                 m_data.append(&m_receiveBuf[bufPos], valueLength);
 404             m_data.append('\n');
 405         } else if (field == "event") {
 406             m_eventName = valueLength ? AtomicString(&m_receiveBuf[bufPos], valueLength) : "";
 407         } else if (field == "id") {
 408             m_currentlyParsedEventId = valueLength ? AtomicString(&m_receiveBuf[bufPos], valueLength) : "";
 409         } else if (field == "retry") {
 410             if (!valueLength)
 411                 m_reconnectDelay = defaultReconnectDelay;
 412             else {
 413                 String value(&m_receiveBuf[bufPos], valueLength);
 414                 bool ok;
 415                 unsigned long long retry = value.toUInt64(&ok);
 416                 if (ok)
 417                     m_reconnectDelay = retry;
 418             }
 419         }
 420     }
 421 }
 422
 423 void EventSource::stop()
 424 {
 425     close();
 426 }
 427
 428 bool EventSource::hasPendingActivity() const
 429 {
 430     return m_state != CLOSED;
 431 }
 432
 433 PassRefPtrWillBeRawPtr<MessageEvent> EventSource::createMessageEvent()
 434 {
 435     RefPtrWillBeRawPtr<MessageEvent> event = MessageEvent::create();
 436     event->initMessageEvent(m_eventName.isEmpty() ? EventTypeNames::message : m_eventName, false, false, SerializedScriptValue::create(String(m_data)), m_eventStreamOrigin, m_lastEventId, 0, nullptr);
 437     m_data.clear();
 438     return event.release();
 439 }
 440
 441 } // namespace blink