logger.isLevelEnabled('off') not functioning as expected

[thernstig]

import log4js from 'log4js';
const logger = log4js.getLogger('test');
logger.level = 'error';
console.log(logger.isLevelEnabled('error'));
console.log(logger.isLevelEnabled('info'));
console.log(logger.isLevelEnabled('off'));

I would expect the last statement to print false but it prints true.

The end goal is to do something like this:

import log4js from 'log4js';
if (logger.isLevelEnabled('off')) {
  logger.level = 'error';
  // do something here
}

[lamweili]

Based on my memory, OFF is the highest log level. So it would always return true.

log4js-node/lib/levels.js

Lines 96 to 104 in cfab25c

	ALL: { value: Number.MIN_VALUE, colour: 'grey' },
	TRACE: { value: 5000, colour: 'blue' },
	DEBUG: { value: 10000, colour: 'cyan' },
	INFO: { value: 20000, colour: 'green' },
	WARN: { value: 30000, colour: 'yellow' },
	ERROR: { value: 40000, colour: 'red' },
	FATAL: { value: 50000, colour: 'magenta' },
	MARK: { value: 9007199254740992, colour: 'grey' }, // 2^53
	OFF: { value: Number.MAX_VALUE, colour: 'grey' },

[thernstig]

@lamweili is there any way to achieve what I want? In most of the code we enable some global logging configuration, but in some pieces of code we need to check if log4js.configure() ever been called or initialized in any way. I could not find any existing API to do this.

[lamweili]

I don't think there is any way to check at the moment. I think this can be a good feature to have. 🤗

Give me some time, should be easy to implement. Maybe it should return the existing configuration if configured.

[lamweili]

@thernstig, would the new API log4js.isConfigured() returning a boolean be sufficient?

While I can possibly cache the passed-in configuration and return that, it would not reflect any programmatical changes as they don't go through the same flow. That would be outdated and not an accurate representation of the latest configuration.

[lamweili]

Merging the PR automatically closed this issue.
I re-opened this so that you can close it if you are satisfied with the new API.

The documentation for the new API is here at PR #1369.

configured - log4js.isConfigured()

isConfigured method call returns a boolean on whether log4js.configure() was successfully called previously. Implicit log4js.configure() call by log4js.getLogger() will also affect this value.

[thernstig]

@lamweili that is great for my user case at least. Better than before since it did not exist before at all. Thanks 👍

[lamweili]

Did it resolve your issue? You can close this if it does. Thanks!

[thernstig]

@lamweili it works, thanks! I think the information you added about log4js.getLogger() implicitly calls log4js.configure() if not called before, should be mentioned in the API docs about Loggers - log4js.getLogger([category]). But that is an aside.

Another aside is that Docosaurus would have been nice to use :D

[lamweili]

@thernstig, you are right, maybe that should be included in the Loggers - log4js.getLogger([category]) API docs.
Do you want to raise a PR so that it is attributed to you?

As for docusaurus, I'm not familiar, you can have the liberty of another PR! 😄

[lamweili]

@thernstig, in log4js@6.9.0:

• docs: added that log4js.getLogger() may call log4js.configure() #1375

Do you want to close this issue? Or do you have some other needs?

[thernstig]

@lamweili no other needs, I am very happy with your maintenance of the project! 😄