在cpprest客户端中读取服务器已发送事件（SSE）流

Question

我想知道cpprestsdk中是否对服务器发送事件有任何支持？我有一个函数eventGet（），它将发送HTTP请求并从服务器获取响应。但是，该函数只能获取第一个事件，然后才等待。

您知道如何使用此功能从服务器读取多个事件吗？

pplx::task<std::shared_ptr<Object>> MyApi::eventsGet()
{
    std::shared_ptr<ApiConfiguration> apiConfiguration( m_ApiClient->getConfiguration());
    utility::string_t path = utility::conversions::to_string_t("/Events");

    std::map<utility::string_t, utility::string_t> queryParams;
    std::map<utility::string_t, utility::string_t> headerParams( apiConfiguration->getDefaultHeaders());
    std::map<utility::string_t, utility::string_t> formParams;
    std::map<utility::string_t, std::shared_ptr<HttpContent>> fileParams;
    std::unordered_set<utility::string_t> responseHttpContentTypes;

    responseHttpContentTypes.insert( utility::conversions::to_string_t("text/event-stream"));
    utility::string_t responseHttpContentType;
    headerParams[utility::conversions::to_string_t("Accept")] = responseHttpContentType;
    std::unordered_set<utility::string_t> consumeHttpContentTypes;
    std::shared_ptr<IHttpBody> httpBody;
    utility::string_t requestHttpContentType;

    return m_ApiClient->callApi(path, utility::conversions::to_string_t("GET"), queryParams, 
    httpBody, headerParams, formParams, fileParams, requestHttpContentType)
    .then([=](web::http::http_response response)
    {
        auto stream = response.body();

        Concurrency::streams::container_buffer<std::string> line;
        stream.read_line(line).then([line](size_t bytesRead)->size_t 
        {
            const std::string &readText = line.collection();
            std::cout << readText << std::endl;

            return bytesRead;
        }
    ...

    }
}

我试图在eventGet（）函数内添加一个while循环，以获取每次迭代的response.body（）。然后readText正确地获取了第一个事件数据，但是当发生新事件时，此后打印出空行。

while (true) 
{
    auto stream = response.body();
    Concurrency::streams::container_buffer<std::string> line;   
    stream.read_line(line).then([line](size_t bytesRead) -> size_t 
    {
        const std::string &readText = line.collection();
        std::cout << readText.c_str() << std::endl;
        return bytesRead;
    });
}