Is it possible to use two patterns with the same file logger?

[viseztrance]

Currently I'm using a file_handler to write logs to a file and format them using set_pattern.
While it works well, I'm interested when I start the logger to print some things (OS version etc) to that file without using the pattern.

Is this something that quill supports?

[odygrd]

hey, the pattern is bound to the handler. It is not possible logging 2 different formats to the same handler at the same time at the moment.

If you only want to print some different format when you start the logger and then switch to another one later, it is possible to do something like this

  // Start the backend logging thread
  quill::start();

  // set up a logger for pattern 1
  std::shared_ptr<quill::Handler> fh = quill::file_handler("test.log", "w");

  fh->set_pattern("%(message)");

  quill::Logger* logger_1 = quill::create_logger("logger_1", std::move(fh));

  // Log using the default logger
  LOG_INFO(logger_1, "-- format 1 -- ");
  LOG_INFO(logger_1, "Version: 1.32");
  LOG_INFO(logger_1, "Tag: dadsa123dasda");

  // ensure that the backend worker is no longer doing any work on the file before changing 
  // the pattern
  quill::flush();

  // change the pattern on the file
  std::shared_ptr<quill::Handler> fh2 = quill::file_handler("test.log", "w");
  fh2->set_pattern("%(ascii_time) %(logger_name) %(message)", // format
                   "%D %H:%M:%S.%Qms",                        // timestamp format
                   quill::Timezone::GmtTime);                 // timestamp's timezone

  LOG_INFO(logger_1, "-- format 2 -- ");
  LOG_INFO(logger_1, "Hello from logger 1");

[viseztrance]

This worked great! Thank you for the fast response.