Method on_fetch_items_message

libraries/net/node.cpp:2719–2784

    }

    void node_impl::on_fetch_items_message(peer_connection* originating_peer, const fetch_items_message& fetch_items_message_received)
    {
      VERIFY_CORRECT_THREAD();
      dlog("received items request for ids ${ids} of type ${type} from peer ${endpoint}",
           ("ids", fetch_items_message_received.items_to_fetch)
           ("type", fetch_items_message_received.item_type)
           ("endpoint", originating_peer->get_remote_endpoint()));

      fc::optional<message> last_block_message_sent;

      std::list<message> reply_messages;
      for (const item_hash_t& item_hash : fetch_items_message_received.items_to_fetch)
      {
        try
        {
          message requested_message = _message_cache.get_message(item_hash);
          dlog("received item request for item ${id} from peer ${endpoint}, returning the item from my message cache",
               ("endpoint", originating_peer->get_remote_endpoint())
               ("id", requested_message.id()));
          reply_messages.push_back(requested_message);
          if (fetch_items_message_received.item_type == block_message_type)
            last_block_message_sent = requested_message;
          continue;
        }
        catch (fc::key_not_found_exception&)
        {
           // it wasn't in our local cache, that's ok ask the client
        }

        item_id item_to_fetch(fetch_items_message_received.item_type, item_hash);
        try
        {
          message requested_message = _delegate->get_item(item_to_fetch);
          dlog("received item request from peer ${endpoint}, returning the item from delegate with id ${id} size ${size}",
               ("id", requested_message.id())
               ("size", requested_message.size)
               ("endpoint", originating_peer->get_remote_endpoint()));
          reply_messages.push_back(requested_message);
          if (fetch_items_message_received.item_type == block_message_type)
            last_block_message_sent = requested_message;
          continue;
        }
        catch (fc::key_not_found_exception&)
        {
          reply_messages.push_back(item_not_available_message(item_to_fetch));
          dlog("received item request from peer ${endpoint} but we don't have it",
               ("endpoint", originating_peer->get_remote_endpoint()));
        }
      }

      // if we sent them a block, update our record of the last block they've seen accordingly
      if (last_block_message_sent)
      {
        graphene::net::block_message block = last_block_message_sent->as<graphene::net::block_message>();
        originating_peer->last_block_delegate_has_seen = block.block_id;
        originating_peer->last_block_time_delegate_has_seen = _delegate->get_block_time(block.block_id);
      }