'debug' level is getting directed to stderr instead of stdout

Setup

• winston version 2.2.0
• node version 4.4.7

Repro Steps

1. Save the following into a file named app.js:

   'use strict';
   
   const winston = require('winston');
   const log = new winston.Logger({
   levels: {
     error: 3,
     warning: 4,
     notice: 5,
     info: 6,
     debug: 7,
   },
   transports: [
     new (winston.transports.Console)({
       level: 'debug',
     }),
   ],
   });
   
   log.error('test error');
   log.warning('test warning');
   log.notice('test notice');
   log.info('test info');
   log.debug('test debug');
   

2. Run the app with command: node app.js > app.log 2>err.log

3. View the contents of err.log and notice that the log.error and log.debug output both ended up in there (former expected, latter not expected). View the contents of app.log and notice that the log.warning, log.notice, and log.info output all ended up in there (as expected).

4. Edit app.js to find/replace all 4 instances of ‘debug’ with any other word - e.g. ‘debugz’.

5. Run the app (again) with (the same) command: node app.js > app.log 2>err.log

6. Notice how all the stuff ends up in the same file, except that the log.debugz output is now in app.log and not in err.log.

[rhbecker]

Found the answer here: https://github.com/winstonjs/winston/blob/master/docs/transports.md

… i.e. setting the levels to log to stderr instead of stdout via stderrLevels transport option.

FWIW, I didn’t find it very intuitive that this option would default to ['error', 'debug'], but that may be based on my own ignorance of how that default would make sense.

I’ll let someone on the project close this issue after reading this feedback, but I need no additional help.

[jasperkuperus]

Debug logging does not indicate an error in my eyes. Good that it can be changed via stderrLevels, but shouldn’t the default be ['error'] in stead of ['error', 'debug']?