@fundev-pro/log-ts (JS/TS version)

TypeScript/JavaScript logging library with flexible configuration and multiple output targets.

For general configuration examples, see the main README.md.
This document covers JS/TS-specific features and built-in presets.

Installation

npm install @fundev-pro/log-ts

Quick Start

import { createLogger } from '@fundev-pro/log-ts';

const logger = createLogger('MyApp');

logger.trace('Trace message');
logger.debug('Debug message');
logger.info('Info message');
logger.warn('Warning message');
logger.error('Error message');
logger.fatal('Fatal error');

Note: When you call createLogger without a config, it automatically uses consoleLogConfig() as the default.

Customizing the built-in console preset

If you want to modify the default console configuration (e.g., change rules or levels):

import { createLogger, LogLevel } from '@fundev-pro/log-ts';
import { consoleLogConfig } from '@fundev-pro/log-ts/console';

// Customize the preset
const customConfig = consoleLogConfig();
customConfig.rules = [{ pattern: 'MyApp', minLevel: LogLevel.Warn, writeTo: 'console' }];
const logger = createLogger('MyApp', customConfig);

What's included in consoleLogConfig

• Timestamp: formatted as HH:MM:SS.mmm
• Log level: padded dynamically (e.g., TRACE, DEBUG, INFO)
• Logger name: padded dynamically
• Color rules for browser console:
  • Trace → darkgray
  • Debug → cyan
  • Info → white
  • Warn → orange
  • Error → red
• Layout: timestamp|level|logger| ...messages

Platform-specific features

consoleTarget from @fundev-pro/log-ts/console

import { consoleTarget } from '@fundev-pro/log-ts/console';
import { configLog, LogLevel } from '@fundev-pro/log-ts';

const config = configLog({
    minLevelDefault: LogLevel.Debug,
    maxLevelDefault: LogLevel.Error,

    targets: {
        console: consoleTarget({
            layout: e => [`[${e.levelName}]`, ...e.message],
        }),
    },

    timestampProvider: () => Date.now(),

    rules: [{ pattern: '*', writeTo: 'console' }],
});

Angular integration (concept)

You can integrate the logger into Angular:

• create a shared logConfig with configLog
• provide it via DI
• create helper injectLogger that calls createLogger with config