@zzkit/xlog

here is an invasive logging library that hooks into the global console object to enable logging with different transports and formatting.

Installation

npm install @zzkit/xlog

Usage

To start logging, instantiate the Logger class with configuration options:

import { Logger, transports, filters, formatters } from '@zzkit/xlog';

const logger = new Logger({
  transports: [
    new transports.console(),
    new transports.dailyFile({
      filename: (date) => `./logs/log-${date.toISOString().split('T')[0]}.log` 
    })
  ],
  formatters: [formatters.simple],  
});

This will log to the console and daily log files.

Then you can use the regular console methods for logging:

console.log('Hello world!'); 

console.debug('Debug message');

Configuration

The Logger constructor takes a configuration object with the following properties:

• transports - Array of Transport instances for handling logs
• formatters - Array of LogFormatter functions for transforming log data
• hidden_orig_console - Whether to suppress logs from the original console (default false)

Built-in Transports

• transports.console - Logs to console
• transports.file - Logs to a file
• transports.dailyFile - Logs to daily file, removes old files

Built-in Formatters

• formatters.log.label - Adds label data to log
• formatters.log.secret - Hidden secret pattern in message

Built-in Transport Formatters

• formatters.transport.line1_colorize - Colorized single line log
• formatters.transport.line1 - Single line log
• formatters.transport.apache - Apache common log format
• formatters.transport.json - JSON format
• formatters.transport.json_no_stack - JSON without stack trace

Filters

You can filter logs by log level:

import { filters } from '@zzkit/xlog';

// Only log warnings and errors
const logger = new Logger({
  transports: [
    new transports.console({
      filter: filters.not_level(LogLevels.info) 
    })
  ]  
});

Full usage

see file ./demo1.ts.

License

MIT