simple-console-log-level

A dead simple logger with log level support, no dependencies and support all environments:

• Web
• Node
• Weapp(微信小程序) - 做这个主要是因为需要在微信小程序里面用, 找了一圈发现没有合适的库(必须没有任何依赖)
• ...

Will log to STDOUT or STDERR depending on the chosen log level. It uses console.trace, console.log, console.info, console.warn and console.error and hence supports the same API.

Log levels supported: trace, log, info, warn and error.

Installation

npm install simple-console-log-level --save

Example usage

var Logger = require('simple-console-log-level');
 
var logger = new Logger({
    level: Logger.LEVEL_LOG
});
 
logger.trace('trace'); // will not do anything
logger.log('log');     // will output 'log'
logger.info('info');   // will output 'info'
logger.warn('warn');   // will output 'warn'
logger.error('error'); // will output 'error'

Options

Configure the logger by passing an options object:

var Logger = require('simple-console-log-level');
 
var logger = new Logger({
    level: Logger.LEVEL_LOG,
    prefix: function() {
        return new Date().toISOString() + ' [' + this.options.level + ']';
    }
});

level

A string to specify the log level. Defaults to Logger.LEVEL_LOG.

All support levels(more below is more higher level).

• Logger.LEVEL_TRACE -- Weapp debug mode(调试模式) could not output(in vConsole) this level's logs
• Logger.LEVEL_LOG
• Logger.LEVEL_INFO
• Logger.LEVEL_WARN
• Logger.LEVEL_ERROR

More higher than you setting level will output, more lower will not. Example: level: Logger.LEVEL_INFO, log levels below Logger.LEVEL_INFO(include itself) will output, log levels above Logger.LEVEL_INFO will not output.

prefix

Specify this option if you want to set a prefix for all log messages. This must be a string or a function that returns a string.

Will get the level of the currently logged message as the first argument.

Thanks

• watson/console-log-level