No implicit conversion from b_string to string on arrays?

Arreme_N_A · February 25, 2023, 5:07pm

Hello! I have a quick question just to make sure I’m not actually missing something.
I have just upgraded to version 3.8-pre (master) from 3.6. Before, I could get a string element like “element.get_utf8().value.to_string()”. Now get_utf8() is deprecated and the method get_string() gives the following error.

img_array is of type bsoncxx::v_noabi::array::view
Also there is no to_string method anymore.

From bsoncxx::document::view this conversion is implicit and seems to work.

As said, is this normal?

Rishabh_Bisht · March 2, 2023, 8:29am

Hi @Arreme_N_A,

You can refer to the example shown here for this conversion

github.com

mongodb/mongo-cxx-driver/blob/master/examples/mongocxx/change_streams.cpp#L34


      
          #include <mongocxx/pool.hpp>
          #include <mongocxx/uri.hpp>
          
          
namespace {
          
          
std::string get_server_version(const mongocxx::client& client) {
              bsoncxx::builder::basic::document server_status{};
              server_status.append(bsoncxx::builder::basic::kvp("serverStatus", 1));
              bsoncxx::document::value output = client["test"].run_command(server_status.extract());
          
          
    return bsoncxx::string::to_string(output.view()["version"].get_string().value);
          }
          
          
void watch_until(const mongocxx::client& client,
                           const std::chrono::time_point<std::chrono::system_clock> end) {
              mongocxx::options::change_stream options;
              // Wait up to 1 second before polling again.
              const std::chrono::milliseconds await_time{1000};
              options.max_await_time(await_time);
          
          
    auto collection = client["db"]["coll"];