ceph/src/boost/libs/log/example/doc/sinks_multifile.cpp

   1 /*
   2  *          Copyright Andrey Semashev 2007 - 2015.
   3  * Distributed under the Boost Software License, Version 1.0.
   4  *    (See accompanying file LICENSE_1_0.txt or copy at
   5  *          http://www.boost.org/LICENSE_1_0.txt)
   6  */
   7
   8 #include <string>
   9 #include <iostream>
  10 #include <boost/smart_ptr/shared_ptr.hpp>
  11 #include <boost/smart_ptr/make_shared_object.hpp>
  12 #include <boost/log/core.hpp>
  13 #include <boost/log/expressions.hpp>
  14 #include <boost/log/sinks/sync_frontend.hpp>
  15 #include <boost/log/sinks/text_multifile_backend.hpp>
  16 #include <boost/log/sources/logger.hpp>
  17 #include <boost/log/sources/record_ostream.hpp>
  18 #include <boost/log/attributes/scoped_attribute.hpp>
  19
  20 namespace logging = boost::log;
  21 namespace src = boost::log::sources;
  22 namespace expr = boost::log::expressions;
  23 namespace sinks = boost::log::sinks;
  24 namespace keywords = boost::log::keywords;
  25
  26 //[ example_sinks_multifile
  27 void init_logging()
  28 {
  29     boost::shared_ptr< logging::core > core = logging::core::get();
  30
  31     boost::shared_ptr< sinks::text_multifile_backend > backend =
  32         boost::make_shared< sinks::text_multifile_backend >();
  33
  34     // Set up the file naming pattern
  35     backend->set_file_name_composer
  36     (
  37         sinks::file::as_file_name_composer(expr::stream << "logs/" << expr::attr< std::string >("RequestID") << ".log")
  38     );
  39
  40     // Wrap it into the frontend and register in the core.
  41     // The backend requires synchronization in the frontend.
  42     typedef sinks::synchronous_sink< sinks::text_multifile_backend > sink_t;
  43     boost::shared_ptr< sink_t > sink(new sink_t(backend));
  44
  45     // Set the formatter
  46     sink->set_formatter
  47     (
  48         expr::stream
  49             << "[RequestID: " << expr::attr< std::string >("RequestID")
  50             << "] " << expr::smessage
  51     );
  52
  53     core->add_sink(sink);
  54 }
  55 //]
  56
  57 void logging_function()
  58 {
  59     src::logger lg;
  60     BOOST_LOG(lg) << "Hello, world!";
  61 }
  62
  63 int main(int, char*[])
  64 {
  65     init_logging();
  66
  67     {
  68         BOOST_LOG_SCOPED_THREAD_TAG("RequestID", "Request1");
  69         logging_function();
  70     }
  71     {
  72         BOOST_LOG_SCOPED_THREAD_TAG("RequestID", "Request2");
  73         logging_function();
  74     }
  75
  76     return 0;
  77 }