C++ ThreadableLoaderOptions::setDataBufferingPolicy方法代码示例

void EventSource::connect()
{
    ASSERT(m_state == CONNECTING);
    ASSERT(!m_requestInFlight);

    ResourceRequest request(m_url);
    request.setHTTPMethod("GET");
    request.setHTTPHeaderField(HTTPHeaderName::Accept, "text/event-stream");
    request.setHTTPHeaderField(HTTPHeaderName::CacheControl, "no-cache");
    if (!m_lastEventId.isEmpty())
        request.setHTTPHeaderField(HTTPHeaderName::LastEventID, m_lastEventId);

    SecurityOrigin* origin = scriptExecutionContext()->securityOrigin();

    ThreadableLoaderOptions options;
    options.setSendLoadCallbacks(SendCallbacks);
    options.setSniffContent(DoNotSniffContent);
    options.setAllowCredentials((origin->canRequest(m_url) || m_withCredentials) ? AllowStoredCredentials : DoNotAllowStoredCredentials);
    options.preflightPolicy = PreventPreflight;
    options.crossOriginRequestPolicy = UseAccessControl;
    options.setDataBufferingPolicy(DoNotBufferData);
    options.securityOrigin = origin;

    m_loader = ThreadableLoader::create(scriptExecutionContext(), this, request, options);

    if (m_loader)
        m_requestInFlight = true;
}

void EventSource::connect()
{
    ASSERT(m_state == CONNECTING);
    ASSERT(!m_requestInFlight);

    ResourceRequest request { m_url };
    request.setHTTPMethod("GET");
    request.setHTTPHeaderField(HTTPHeaderName::Accept, "text/event-stream");
    request.setHTTPHeaderField(HTTPHeaderName::CacheControl, "no-cache");
    if (!m_lastEventId.isEmpty())
        request.setHTTPHeaderField(HTTPHeaderName::LastEventID, m_lastEventId);

    ThreadableLoaderOptions options;
    options.setSendLoadCallbacks(SendCallbacks);
    options.setSniffContent(DoNotSniffContent);
    options.credentials = m_withCredentials ? FetchOptions::Credentials::Include : FetchOptions::Credentials::SameOrigin;
    options.preflightPolicy = PreventPreflight;
    options.mode = FetchOptions::Mode::Cors;
    options.setDataBufferingPolicy(DoNotBufferData);
    options.contentSecurityPolicyEnforcement = scriptExecutionContext()->shouldBypassMainWorldContentSecurityPolicy() ? ContentSecurityPolicyEnforcement::DoNotEnforce : ContentSecurityPolicyEnforcement::EnforceConnectSrcDirective;

    m_loader = ThreadableLoader::create(scriptExecutionContext(), this, request, options);

    // FIXME: Can we just use m_loader for this, null it out when it's no longer in flight, and eliminate the m_requestInFlight member?
    if (m_loader)
        m_requestInFlight = true;
}

void FetchLoader::start(ScriptExecutionContext& context, const FetchRequest& request)
{
    // FIXME: Compute loading options according fetch options.
    ThreadableLoaderOptions options;
    options.setSendLoadCallbacks(SendCallbacks);
    options.setSniffContent(DoNotSniffContent);
    options.setDataBufferingPolicy(DoNotBufferData);
    options.preflightPolicy = ConsiderPreflight;
    options.setAllowCredentials(AllowStoredCredentials);
    options.crossOriginRequestPolicy = DenyCrossOriginRequests;
    options.contentSecurityPolicyEnforcement = ContentSecurityPolicyEnforcement::DoNotEnforce;

    m_loader = ThreadableLoader::create(&context, this, request.internalRequest(), options);
}

void DocumentThreadableLoader::loadRequest(const ResourceRequest& request, SecurityCheckPolicy securityCheck)
{
    // Any credential should have been removed from the cross-site requests.
    const URL& requestURL = request.url();
    m_options.setSecurityCheck(securityCheck);
    ASSERT(m_sameOriginRequest || requestURL.user().isEmpty());
    ASSERT(m_sameOriginRequest || requestURL.pass().isEmpty());

    if (m_async) {
        ThreadableLoaderOptions options = m_options;
        options.setClientCredentialPolicy(DoNotAskClientForCrossOriginCredentials);
        if (m_actualRequest) {
            // Don't sniff content or send load callbacks for the preflight request.
            options.setSendLoadCallbacks(DoNotSendCallbacks);
            options.setSniffContent(DoNotSniffContent);
            // Keep buffering the data for the preflight request.
            options.setDataBufferingPolicy(BufferData);
        }

        CachedResourceRequest newRequest(request, options);
        if (RuntimeEnabledFeatures::sharedFeatures().resourceTimingEnabled())
            newRequest.setInitiator(m_options.initiator);
        ASSERT(!m_resource);
        m_resource = m_document.cachedResourceLoader().requestRawResource(newRequest);
        if (m_resource)
            m_resource->addClient(this);

        return;
    }
    
    // FIXME: ThreadableLoaderOptions.sniffContent is not supported for synchronous requests.
    RefPtr<SharedBuffer> data;
    ResourceError error;
    ResourceResponse response;
    unsigned long identifier = std::numeric_limits<unsigned long>::max();
    if (m_document.frame())
        identifier = m_document.frame()->loader().loadResourceSynchronously(request, m_options.allowCredentials(), m_options.clientCredentialPolicy(), error, response, data);

    if (!error.isNull() && response.httpStatusCode() <= 0) {
        if (requestURL.isLocalFile()) {
            // We don't want XMLHttpRequest to raise an exception for file:// resources, see <rdar://problem/4962298>.
            // FIXME: XMLHttpRequest quirks should be in XMLHttpRequest code, not in DocumentThreadableLoader.cpp.
            didReceiveResponse(identifier, response);
            didFinishLoading(identifier, 0.0);
            return;
        }
        m_client->didFail(error);
        return;
    }

    // FIXME: FrameLoader::loadSynchronously() does not tell us whether a redirect happened or not, so we guess by comparing the
    // request and response URLs. This isn't a perfect test though, since a server can serve a redirect to the same URL that was
    // requested. Also comparing the request and response URLs as strings will fail if the requestURL still has its credentials.
    bool didRedirect = requestURL != response.url();
    if (didRedirect && (!isAllowedByContentSecurityPolicy(response.url(), didRedirect) || !isAllowedRedirect(response.url()))) {
        m_client->didFailRedirectCheck();
        return;
    }

    didReceiveResponse(identifier, response);

    if (data)
        didReceiveData(identifier, data->data(), data->size());
    didFinishLoading(identifier, 0.0);
}

void XMLHttpRequest::createRequest(ExceptionCode& ec)
{
    // Only GET request is supported for blob URL.
    if (m_url.protocolIs("blob") && m_method != "GET") {
        ec = XMLHttpRequestException::NETWORK_ERR;
        return;
    }

    m_sendFlag = true;

    // The presence of upload event listeners forces us to use preflighting because POSTing to an URL that does not
    // permit cross origin requests should look exactly like POSTing to an URL that does not respond at all.
    // Also, only async requests support upload progress events.
    bool uploadEvents = false;
    if (m_async) {
        m_progressEventThrottle.dispatchProgressEvent(eventNames().loadstartEvent);
        if (m_requestEntityBody && m_upload) {
            uploadEvents = m_upload->hasEventListeners();
            m_upload->dispatchProgressEvent(eventNames().loadstartEvent);
        }
    }

    m_sameOriginRequest = securityOrigin()->canRequest(m_url);

    // We also remember whether upload events should be allowed for this request in case the upload listeners are
    // added after the request is started.
    m_uploadEventsAllowed = m_sameOriginRequest || uploadEvents || !isSimpleCrossOriginAccessRequest(m_method, m_requestHeaders);

    ResourceRequest request(m_url);
    request.setRequester(ResourceRequest::Requester::XHR);
    request.setHTTPMethod(m_method);

    if (m_requestEntityBody) {
        ASSERT(m_method != "GET");
        ASSERT(m_method != "HEAD");
        request.setHTTPBody(m_requestEntityBody.release());
    }

    if (!m_requestHeaders.isEmpty())
        request.setHTTPHeaderFields(m_requestHeaders);

    ThreadableLoaderOptions options;
    options.setSendLoadCallbacks(SendCallbacks);
    options.setSniffContent(DoNotSniffContent);
    options.preflightPolicy = uploadEvents ? ForcePreflight : ConsiderPreflight;
    options.setAllowCredentials((m_sameOriginRequest || m_includeCredentials) ? AllowStoredCredentials : DoNotAllowStoredCredentials);
    options.crossOriginRequestPolicy = UseAccessControl;
    options.securityOrigin = securityOrigin();
    options.initiator = cachedResourceRequestInitiators().xmlhttprequest;

    if (m_responseTypeCode == ResponseTypeArrayBuffer)
        options.setDataBufferingPolicy(DoNotBufferData);

    if (m_timeoutMilliseconds) {
        if (!m_async)
            request.setTimeoutInterval(m_timeoutMilliseconds / 1000.0);
        else {
            m_sendingTime = std::chrono::steady_clock::now();
            m_timeoutTimer.startOneShot(std::chrono::milliseconds { m_timeoutMilliseconds });
        }
    }

    m_exceptionCode = 0;
    m_error = false;

    if (m_async) {
        if (m_upload)
            request.setReportUploadProgress(true);

        // ThreadableLoader::create can return null here, for example if we're no longer attached to a page or if a content blocker blocks the load.
        // This is true while running onunload handlers.
        // FIXME: Maybe we need to be able to send XMLHttpRequests from onunload, <http://bugs.webkit.org/show_bug.cgi?id=10904>.
        m_loader = ThreadableLoader::create(scriptExecutionContext(), this, request, options);

        // Neither this object nor the JavaScript wrapper should be deleted while
        // a request is in progress because we need to keep the listeners alive,
        // and they are referenced by the JavaScript wrapper.
        setPendingActivity(this);
        if (!m_loader) {
            m_sendFlag = false;
            m_timeoutTimer.stop();
            m_networkErrorTimer.startOneShot(0);
        }
    } else {
        InspectorInstrumentation::willLoadXHRSynchronously(scriptExecutionContext());
        ThreadableLoader::loadResourceSynchronously(scriptExecutionContext(), request, *this, options);
        InspectorInstrumentation::didLoadXHRSynchronously(scriptExecutionContext());
    }

    if (!m_exceptionCode && m_error)
        m_exceptionCode = XMLHttpRequestException::NETWORK_ERR;
    ec = m_exceptionCode;
}