template code for spdlog library

spdlog-templ.cpp

#include <memory>
#include <vector>
#define SPDLOG_ACTIVE_LEVEL SPDLOG_LEVEL_DEBUG
#include "spdlog/spdlog.h"
#include "spdlog/sinks/stdout_color_sinks.h"
#include "spdlog/sinks/daily_file_sink.h"
#include "spdlog/sinks/rotating_file_sink.h"

int main(int argc, char* argv[])
{
#if 1
  // https://github.com/gabime/spdlog/wiki/4.-Sinks
  std::vector<spdlog::sink_ptr> sinks = {
    std::make_shared<spdlog::sinks::stdout_color_sink_mt>(),
    std::make_shared<spdlog::sinks::daily_file_sink_mt>("daily.log", 23, 59),  // 23:59
    std::make_shared<spdlog::sinks::rotating_file_sink_mt>("rotate.log", 10*1024*1024, 5)  // 10MB x 5files
  };
  spdlog::set_default_logger(std::make_shared<spdlog::logger>("multi_sink", begin(sinks), end(sinks)));
#else
  // default logger = spdlog::sinks::stdout_color_sink_mt
  // suffix "_mt" = multi-thread / "_st" = single-thread support.
#endif

  // set loglevel at runtime
  const auto loglevel = "info";
  spdlog::set_level(spdlog::level::from_str(loglevel));

#if 0
  // https://github.com/gabime/spdlog/blob/v2.x/tests/test_cfg.cpp
  //#include "spdlog/cfg/argv.h"
  spdlog::cfg::load_argv_levels(argc, argv);
#endif

  // https://github.com/gabime/spdlog/wiki/3.-Custom-formatting
  spdlog::set_pattern("%+");  // spdlog default
  spdlog::set_pattern("[%D %T] %^[%l]%$ %v");

  SPDLOG_TRACE("trace val={}", 42);  // disabled at compile time (see SPDLOG_ACTIVE_LEVEL)
  SPDLOG_DEBUG("debug");  // disabled at runtime (see set_level)
  SPDLOG_INFO("info");
  SPDLOG_WARN("warn");
  SPDLOG_ERROR("error");
  SPDLOG_CRITICAL("critical");
}