LiteRT/Logger


A logs writer for LiteRT framework.

Features

- [x] Log stack trace.
- [x] Enable/Disable log levels.
- [x] Custom levels.
- [x] Custom formats.
- [x] Custom output drivers.

Requirement

- TypeScript v5.0.0 (or newer)
- Node.js v18.0.0 (or newer)

Installation

Install by NPM:

``sh
npm i @litert/logger --save
`

Quick Start

Simple usage:

`ts
// The imported module is a LoggerFactory singleton object, so you can use it directly.
import LoggerFactory from "@litert/logger";

const logger = LoggerFactory.createLogger('Demo');

logger.info('Hello, world!');
logger.warning('Hello, world!');

// Now, just disable a level, and it will not be printed.
logger.setLevelOptions({ levels: ['error'], enabled: false });

logger.error('Hello, world! (WILL NOT BE PRINTED)');

// let's turn on the stack trace, print 2 lines of stack trace.
//
// without specifying levels, all levels will be affected.
logger.setLevelOptions({ traceDepth: 2 });

logger.notice('Hello, world!');
`

Use custom log formatter:

`ts
import LoggerFactory from "@litert/logger";

LoggerFactory.setLevelOptions({ enabled: true });

const logger = LoggerFactory.createLogger('Demo');

logger.setLevelOptions({
formatter: function(log, subj, lv, dt, traces): string {

if (traces?.length) {

return ${new Date(dt).toISOString()} - ${subj} - ${lv} - ${log}

${traces.join('\n ')}
;
}

return ${new Date(dt).toISOString()} - ${subj} - ${lv} - ${log};
}
});

logger.info('Hello, world!');
logger.warning('Hello, world!');

logger.setLevelOptions({ traceDepth: 2 });

logger.error('Hello, world!');
``

More Examples:

- Quick Start
- Custom log levels
- Custom log formatter
- Custom log output driver
- Using factory

License

This library is published under Apache-2.0 license.