Program Listing for File multipart_stream.hpp

Return to documentation for file (include/web_video_server/multipart_stream.hpp)

// Copyright (c) 2014, Worcester Polytechnic Institute
// Copyright (c) 2024, The Robot Web Tools Contributors
// All rights reserved.
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//    * Redistributions in binary form must reproduce the above copyright
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#pragma once

#include <queue>
#include <memory>
#include <vector>
#include <string>

#include "rclcpp/rclcpp.hpp"
#include "async_web_server_cpp/http_connection.hpp"

namespace web_video_server
{

struct PendingFooter
{
  std::chrono::steady_clock::time_point timestamp;
  std::weak_ptr<std::string> contents;
};

class MultipartStream
{
public:
  MultipartStream(
    async_web_server_cpp::HttpConnectionPtr & connection,
    const std::string & boundry = "boundarydonotcross",
    std::size_t max_queue_size = 1);

  void sendInitialHeader();
  void sendPartHeader(
    const std::chrono::steady_clock::time_point & time, const std::string & type,
    size_t payload_size);
  void sendPartFooter(const std::chrono::steady_clock::time_point & time);
  void sendPartAndClear(
    const std::chrono::steady_clock::time_point & time, const std::string & type,
    std::vector<unsigned char> & data);
  void sendPart(
    const std::chrono::steady_clock::time_point & time, const std::string & type,
    const boost::asio::const_buffer & buffer,
    async_web_server_cpp::HttpConnection::ResourcePtr resource);

private:
  bool isBusy();

private:
  const std::size_t max_queue_size_;
  async_web_server_cpp::HttpConnectionPtr connection_;
  std::string boundry_;
  std::queue<PendingFooter> pending_footers_;
};

}  // namespace web_video_server