Feat: Allow log.categories configuration

[klouvas]

Use case:
Enable specific logger category to output debug logs in production for debugging instead of enabling debug level logs for the whole application.

Usage example:

// services/serviceA.js
const logger = require('@workablehr/orka').getLogger('serviceA');

function serviceFn(){
  logger.debug('start');
  // doSomething
  logger.debug('end');
}
module.exports = serviceFn;

// config/env/staging.json
"log": {
  "level": "info",
  "categories": {
  "serviceA": {
    "appenders": ['json'],
     "level": "debug"
  }
}

What should be done:

• [] Add documentation about available appenders
• [] use config.log.categories in Log4js.configure (https://github.com/Workable/orka/blob/master/src/initializers/log4js/index.ts )

[SokratisVidros]

Log level is a well used strategy. TBH I really like this approach https://www.npmjs.com/package/debug. It seems more hackable in production.

[nikostoulas]

@SokratisVidros @klouvas Note that require('debug') is a core Nodejs module. There is no library needed.
Actually it is not a core module but most modules already have it. So almost in any app it is already installed.

@klouvas Your suggestion would be a very nice to have. Ideally since log4js supports subcategories (eg if you have a logger: 'db.user.transaction' you could set different level of logging for all db.* loggers), you would set an env eg LOG_CATEGORY_DB=debug and you would be good to go.
I think the effort to support sth like this would be significant (You need extra code in apps too to include in config all possible categories). The alternative suggested by @SokratisVidros is very easy to include it in any app.
I would use 'debug' and leave this as an open issue in orka for whenever we have the time to see it.

[klouvas]

i thought that debug had only enable/disable capabilities. I have no strong feelings about any of this approaches. Ideally i would prefer to use the approach already used by most of the company's teams.