include/async_resolve.hpp

#ifndef THIRD_PARTY_GBMCWEB_INCLUDE_ASYNC_RESOLVE_H_
#define THIRD_PARTY_GBMCWEB_INCLUDE_ASYNC_RESOLVE_H_

#include <cstdint>
#include <string>
#include <tuple>
#include <vector>

#include "boost/asio/ip/address.hpp"  // NOLINT
#include "boost/asio/ip/basic_endpoint.hpp"  // NOLINT
#include "boost/asio/ip/tcp.hpp"  // NOLINT
#include "logging.hpp"
#include "managed_store.hpp"

namespace crow {

namespace async_resolve {

class Resolver {
 public:
  Resolver() = default;

  ~Resolver() = default;

  Resolver(const Resolver&) = delete;
  Resolver(Resolver&&) = delete;
  Resolver& operator=(const Resolver&) = delete;
  Resolver& operator=(Resolver&&) = delete;

  template <typename ResolveHandler>
  void asyncResolve(const std::string& host, uint16_t port,
                    ResolveHandler&& handler) {
    BMCWEB_LOG_DEBUG << "Trying to resolve: " << host << ":" << port;
    uint64_t flag = 0;
    managedStore::GetManagedObjectStore()->PostDbusCallToIoContextThreadSafe(
        nullptr,
        [host, port, handler{std::forward<ResolveHandler>(handler)}](
            const boost::system::error_code& ec,
            const std::vector<
                std::tuple<int32_t, int32_t, std::vector<uint8_t>>>& resp,
            const std::string& hostName, const uint64_t flagNum) {
          std::vector<boost::asio::ip::tcp::endpoint> endpointList;
          if (ec) {
            BMCWEB_LOG_ERROR << "Resolve failed: " << ec.message();
            handler(ec, endpointList);
            return;
          }
          BMCWEB_LOG_DEBUG << "ResolveHostname returned: " << hostName << ":"
                           << flagNum;
          // Extract the IP address from the response
          for (auto resolveList : resp) {
            std::vector<uint8_t> ipAddress = std::get<2>(resolveList);
            boost::asio::ip::tcp::endpoint endpoint;
            if (ipAddress.size() == 4)  // ipv4 address
            {
              BMCWEB_LOG_DEBUG << "ipv4 address";
              boost::asio::ip::address_v4 ipv4Addr(
                  {ipAddress[0], ipAddress[1], ipAddress[2], ipAddress[3]});
              endpoint.address(ipv4Addr);
            } else if (ipAddress.size() == 16) {  // ipv6 address
              BMCWEB_LOG_DEBUG << "ipv6 address";
              boost::asio::ip::address_v6 ipv6Addr(
                  {ipAddress[0], ipAddress[1], ipAddress[2], ipAddress[3],
                   ipAddress[4], ipAddress[5], ipAddress[6], ipAddress[7],
                   ipAddress[8], ipAddress[9], ipAddress[10], ipAddress[11],
                   ipAddress[12], ipAddress[13], ipAddress[14], ipAddress[15]});
              endpoint.address(ipv6Addr);
            } else {
              BMCWEB_LOG_ERROR << "Resolve failed to fetch the IP address";
              handler(ec, endpointList);
              return;
            }
            endpoint.port(port);
            BMCWEB_LOG_DEBUG << "resolved endpoint is : " << endpoint;
            endpointList.push_back(endpoint);
          }
          // All the resolved data is filled in the endpointList
          handler(ec, endpointList);
        },
        "org.freedesktop.resolve1", "/org/freedesktop/resolve1",
        "org.freedesktop.resolve1.Manager", "ResolveHostname", 0, host,
        AF_UNSPEC, flag);
  }
};

}  // namespace async_resolve
}  // namespace crow

#endif  // THIRD_PARTY_GBMCWEB_INCLUDE_ASYNC_RESOLVE_H_