Boost ASIO resolver.resolve is deprecated

[JuKu]

Hi,

thank you for your great work!
I really like this header only library for redis!

But i get the following compilation error:

In file included from /cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/3rdparty/redis-cpp/include/redis-cpp/stream.h:31,
                 from /cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/mmo-proxy-server.cpp:15:
/cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/3rdparty/redis-cpp/include/redis-cpp/detail/stream.hpp: In constructor 'rediscpp::detail::stream::stream(std::string_view, std::string_view)':
/cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/3rdparty/redis-cpp/include/redis-cpp/detail/stream.hpp:78:53: error: no matching function for call to 'boost::asio::ip::basic_resolver<boost::asio::ip::tcp>::resolve(std::string_view&, std::string_view&)'
   78 |         auto endpoints = resolver.resolve(host, port);
      |                                                     ^
In file included from /usr/include/boost/asio.hpp:80,
                 from /cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/3rdparty/redis-cpp/include/redis-cpp/detail/stream.hpp:15,
                 from /cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/3rdparty/redis-cpp/include/redis-cpp/stream.h:31,
                 from /cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/mmo-proxy-server.cpp:15:
/usr/include/boost/asio/ip/basic_resolver.hpp:214:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const query&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::query = boost::asio::ip::basic_resolver_query<boost::asio::ip::tcp>]'
  214 |   results_type resolve(const query& q)
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:214:16: note:   candidate expects 1 argument, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:235:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const query&, boost::system::error_code&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::query = boost::asio::ip::basic_resolver_query<boost::asio::ip::tcp>]'
  235 |   results_type resolve(const query& q, boost::system::error_code& ec)
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:235:37: note:   no known conversion for argument 1 from 'std::string_view' {aka 'std::basic_string_view<char>'} to 'const query&' {aka 'const boost::asio::ip::basic_resolver_query<boost::asio::ip::tcp>&'}
  235 |   results_type resolve(const query& q, boost::system::error_code& ec)
      |                        ~~~~~~~~~~~~~^
/usr/include/boost/asio/ip/basic_resolver.hpp:274:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  274 |   results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:274:53: note:   no known conversion for argument 1 from 'std::string_view' {aka 'std::basic_string_view<char>'} to 'std::experimental::fundamentals_v1::string_view' {aka 'std::experimental::fundamentals_v1::basic_string_view<char>'}
  274 |   results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
      |                                                     ^
/usr/include/boost/asio/ip/basic_resolver.hpp:313:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view, boost::system::error_code&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  313 |   results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:313:16: note:   candidate expects 3 arguments, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:356:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view, boost::asio::ip::resolver_base::flags) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  356 |   results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:356:16: note:   candidate expects 3 arguments, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:405:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view, boost::asio::ip::resolver_base::flags, boost::system::error_code&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  405 |   results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:405:16: note:   candidate expects 4 arguments, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:450:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const protocol_type&, std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::protocol_type = boost::asio::ip::tcp; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  450 |   results_type resolve(const protocol_type& protocol,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:450:16: note:   candidate expects 3 arguments, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:492:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const protocol_type&, std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view, boost::system::error_code&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::protocol_type = boost::asio::ip::tcp; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  492 |   results_type resolve(const protocol_type& protocol,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:492:16: note:   candidate expects 4 arguments, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:539:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const protocol_type&, std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view, boost::asio::ip::resolver_base::flags) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::protocol_type = boost::asio::ip::tcp; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  539 |   results_type resolve(const protocol_type& protocol,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:539:16: note:   candidate expects 4 arguments, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:593:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const protocol_type&, std::experimental::fundamentals_v1::string_view, std::experimental::fundamentals_v1::string_view, boost::asio::ip::resolver_base::flags, boost::system::error_code&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::protocol_type = boost::asio::ip::tcp; std::experimental::fundamentals_v1::string_view = std::experimental::fundamentals_v1::basic_string_view<char>]'
  593 |   results_type resolve(const protocol_type& protocol,
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:593:16: note:   candidate expects 5 arguments, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:932:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const endpoint_type&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::endpoint_type = boost::asio::ip::basic_endpoint<boost::asio::ip::tcp>]'
  932 |   results_type resolve(const endpoint_type& e)
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:932:16: note:   candidate expects 1 argument, 2 provided
/usr/include/boost/asio/ip/basic_resolver.hpp:955:16: note: candidate: 'boost::asio::ip::basic_resolver<InternetProtocol>::results_type boost::asio::ip::basic_resolver<InternetProtocol>::resolve(const endpoint_type&, boost::system::error_code&) [with InternetProtocol = boost::asio::ip::tcp; boost::asio::ip::basic_resolver<InternetProtocol>::results_type = boost::asio::ip::basic_resolver_results<boost::asio::ip::tcp>; boost::asio::ip::basic_resolver<InternetProtocol>::endpoint_type = boost::asio::ip::basic_endpoint<boost::asio::ip::tcp>]'
  955 |   results_type resolve(const endpoint_type& e, boost::system::error_code& ec)
      |                ^~~~~~~
/usr/include/boost/asio/ip/basic_resolver.hpp:955:45: note:   no known conversion for argument 1 from 'std::string_view' {aka 'std::basic_string_view<char>'} to 'const endpoint_type&' {aka 'const boost::asio::ip::basic_endpoint<boost::asio::ip::tcp>&'}
  955 |   results_type resolve(const endpoint_type& e, boost::system::error_code& ec)
      |                        ~~~~~~~~~~~~~~~~~~~~~^
make[3]: *** [CMakeFiles/ProxyServer.dir/build.make:63: CMakeFiles/ProxyServer.dir/mmo-proxy-server.cpp.o] Error 1
make[3]: Leaving directory '/cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/cmake-build-debug'
make[2]: *** [CMakeFiles/Makefile2:76: CMakeFiles/ProxyServer.dir/all] Error 2
make[2]: Leaving directory '/cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/cmake-build-debug'
make[1]: *** [CMakeFiles/Makefile2:83: CMakeFiles/ProxyServer.dir/rule] Error 2
make[1]: Leaving directory '/cygdrive/c/Users/Justin/IdeaProjects/MMOPrototyp/mmo-proxy-server/cmake-build-debug'
make: *** [Makefile:118: ProxyServer] Error 2

As screenshot:

The problem is, that the resolve function is already deprecated.

See also: https://www.boost.org/doc/libs/1_66_0/doc/html/boost_asio/reference/ip__tcp/resolver.html

Can you please fix this?

[JuKu]

Maybe this solution works:

stream(const char* host, int port)
    {
        boost::asio::ip::tcp::resolver resolver{io_context_};

        //resolver.resolve() is deprecated
        /*auto endpoints = resolver.resolve(std::move(host), std::move(port));
        auto iter = std::begin(endpoints);
        if (iter == std::end(endpoints))
            throw std::runtime_error{"There is no any endpoint."};*/

        boost::asio::ip::tcp::endpoint endpoint(boost::asio::ip::address::from_string(host), port);

        socket_.connect(endpoint);
        socket_.set_option(boost::asio::ip::tcp::no_delay{});

        stream_ = std::make_unique<stream_type>(socket_);
    }

[JuKu]

I have added a possible PR for this issue:
#2

[tdv]

Hello. I'm really appreciated your commit. However, I need to notice one moment, the function 'from_string' can't recognize 'localhost' like an address. I have to use 'resolver' to use 'localhost' like the address instead of only '127.0.0.1' in order to overcove the problem. That is why I didn't use 'from_string' instead of 'resolver'.
Could you propose a solution with a simultaneously equivalent behavior to use 'localhost' and '127.0.0.1' like the address excluding the solution with 'resolver'?
Thank you again.

[tdv]

I had looked at the latest 'boost' (1.73) again and noticed 'resolver.resolve' among the examples (the link below). Why did you decide the 'resolver.resolve' is deprecated?
https://www.boost.org/doc/libs/1_73_0/libs/beast/example/http/client/sync/http_client_sync.cpp

[JuKu]

@tdv Thanks for your fast answer!

However, I need to notice one moment, the function 'from_string' can't recognize 'localhost' like an address. I have to use 'resolver' to use 'localhost' like the address instead of only '127.0.0.1' in order to overcove the problem. That is why I didn't use 'from_string' instead of 'resolver'.

That's a good point!

I have seen in the documentation, that this function is deprecated:
https://www.boost.org/doc/libs/1_73_0/doc/html/boost_asio/reference/ip__tcp/resolver.html

(**Deprecated**: Use overload with separate host and service parameters.) Perform forward resolution of a query to a list of entries.
—
Perform forward resolution of a query to a list of entries.
—
Perform reverse resolution of an endpoint to a list of entries. 

With Boost 1.66.0 it doesn't works for me (Version 1.66.0 is the highest version available for Cygwin - i don't have tested it with the newest version 1.73.0).

Could you propose a solution with a simultaneously equivalent behavior to use 'localhost' and '127.0.0.1' like the address excluding the solution with 'resolver'?

I could try it, but i don't know Boost very good.

[tdv]

Hello. From your message I noticed you used cygwin thus I decided you used Windows. I don't use Windows more than 10 year, I'm Linux user last 10 years. I can't check particularly your case. Nevertheless, I've tried to fix the problem having seen on your commit. Appealing to that I'd like to propose you trying use it with new macros. If you use header-only version, try to update the library from git and use it with a macros REDISCPP_EASY_ADDRESS_RESOLVE. Please define it before usage the library like below
#define REDISCPP_EASY_ADDRESS_RESOLVE
#include ...

Unfortunatelly, in this case you can't use something like 'localhost', only IP like '127.0.0.1' or others.

Also, report me about results of usage with a new macros, of course, if you would mind :)

Thanks for addressing me about your issue. Hopefully, my commit will fix the problem. I will be waiting for your report about usage of the changes.

[tdv]

Done