Add module name in winston log entries

Question

Is there a possibility to save the current module name in order to be printed automatically in winston log entries when they are called later?

Currently, when I want to print the module name in logs, I have to add it manually:

var logHeader = 'mymodule'

log.info(logHeader + 'Hello')

For example, with debug, you can do (ignore the log format feature %s for now):

var debug = require('debug')('http')
  , name = 'My App'

debug('booting %s', name);

This will prin http prefix before the log:

http booting My App

Can this be done in winston? I have searched in the documentation but I couldn't find anything relevant.

Answer 1

I found a better way to do this.

I added an additional layer over the winston logger, in this case a function, that keeps the module name for each module that needs the logger. So when a module requires my new logger, it actually calls the exported function with the module name, in this case __filename.

log.js

var winston = require('winston')

var winstonLogger = new (winston.Logger)({
    transports: [
        new (winston.transports.File) ({
            filename: 'MyLogs.txt',
            handleExceptions: true,
            humanReadableUnhandledException: true,
            level: 'info',
            timestamp: true,
            json: false
        }),
        new (winston.transports.Console) ({
            level: 'info',
            prettyPrint: true,
            colorize: true,
            timestamp: true
        })
    ]
})

module.exports = function(fileName) {    
    var myLogger = {
        error: function(text) {
            winstonLogger.error(fileName + ': ' + text)
        },
        info: function(text) {
            winstonLogger.info(fileName + ': ' + text)
        }
    }

    return myLogger
}

module1.js

var log = require('log')(__filename)

log.info('Info log example')

info: C:\Users\user1\project\module1.js: Info log example

module2.js

var log = require('log')(__filename)

log.error('Error log example')

error: C:\Users\user1\project\module2.js: Error log example

Also, this way, I didn't need to change anywhere the way I submit a text log; log.info('text') stays exactly like before.