"level" option to transports appears to have no effect

[robbles]

Maybe I've misunderstood this feature, but when I pass a "level" option to a transport, I expect it to restrict output to that level or higher (or perhaps to that level only).

var logger = new (winston.Logger)({
  transports: [
    new (winston.transports.Console)({level: 'warn'}),
  ]
});

logger.debug("this shouldn't show up, but it does");

Instead, it logs everything, include calls to logger.debug. Is there actually a way to restrict logging to a certain level? As an example use case, I want to see debug messages in development, but keep those out of production logs.

The docs seem to indicate that this should work the way I expect though:

Winston allows you to set a level on each transport that specifies the level of messages this transport should log. For example, you could log only errors to the console, with the full logs in a file"

[sbeam]

same issue here. But there is different behaviour for File and Console transports:

File logs everything no matter what level is set to.
set Console to 'debug', then I get only debug and error messages, but not info or warn.

[robbles]

I actually worked out what the problem is here - the default set of levels is just in a strange order, but you can configure them differently. It's not a bug in winston, just an odd default.

The default set is in winston.config.cli.levels and looks like:

{
    silly: 0,
    input: 1,
    verbose: 2,
    prompt: 3,
    info: 4,
    data: 5,
    help: 6,
    warn: 7,
    debug: 8,
    error: 9
}

Which makes very little sense to me since debug is higher than warn.

I changed my loggers to use winston.config.syslog.levels, which matches the more common error levels seen in other logging libraries:

{
    debug: 0,
    info: 1,
    notice: 2,
    warning: 3,
    error: 4,
    crit: 5,
    alert: 6,
    emerg: 7
}

You can pass a level argument to the Logger constructor, and possibly to individual transports:

logger = new (winston.Logger)({
  levels: (winston.config.syslog.levels),
  transports: logTransports
});

Now you can set the level to 'info' and see messages of level 'info' -> 'emerg' and not 'debug'. Hope that helps - this default behaviour should really be documented somewhere since it's different from any other logging library I've used.

[sbeam]

ok, makes sense. syslog levels are so ingrained I didn't even think to question it. thanks for documenting that, big help

[BryanDonovan]

This stumped me too. For future reference, this stems from npmlog, which uses these strange log levels: https://github.com/isaacs/npmlog

[ghost]

+1 /stops banging head on keyboard now.

Plus what @garth shows in this gist. https://gist.github.com/2570757
levels need to be defined in both the Logger options which are passed into the constructor and in the Transport options.

This must be a bug.

[danmilon]

Bumped into this also. It feels so wrong and confusing! Should be documented at least.

[bfirsh]

+1. Spent 15 mins trying to fix this today. This is bizarre.

[mansona]

I think the default should be changed, it seems that a lot of people are being stumped by these odd defaults

[killroy42]

It seems to me the http transport needs this line in the constructor, similar to the console transport:
Transport.call(this, options);

as well as this near the top:
var Transport = require('./transport').Transport;