A logging library designed to simplify the process of logging in your TypeScript applications. With zero dependencies and features such as five log levels, custom log handlers, method decoration options, timestamps, and log level thresholding, you'll have greater control over your log output.
Our library also provides the flexibility to extend its functionality through custom log handlers, enabling you to meet the specific needs of your project. Say goodbye to cluttered and unorganized logs and get started with ts-logger today!💪
- Supports logging at five different levels (:bug: DEBUG, :information_source: INFO, :warning: WARN, :exclamation: ERROR, :fire: FATAL).
- Zero dependencies 🚫
- Support for custom log handlers to extend the functionality of the library. 💬
- Support console, json and file log handlers out of the box. 📦
- Ability to decorate class methods to log their arguments, return values, and execution time. 📊
- Option to include timestamps in logs. 🕰️
- Option to set log level threshold. 🎛️
- Option to log execution time of decorated functions. ⏱️
- Logs can be color-coded based on the log level. 🎨
npm install @origranot/ts-logger
import { Logger } from '@origranot/ts-logger';
const logger = new Logger({
timeStamps: true
});
logger.debug('Debug message');
logger.info('Info message');
logger.warn('Warn message');
logger.error('Error message');
logger.fatal('Fatal message');
logger.info('You can also pass variables', {
metadata: {
foo: 'baz'
}
});- timeStamps (Boolean): Whether to include timestamps in logs (default: false).
- threshold (LOG_LEVEL): The log level threshold, logs with a lower level than the threshold will be ignored (default: 'DEBUG').
- handlers: Array of handlers to process and log the data. (default: ConsoleHandler)
import { Logger, LOG_LEVEL } from '@origranot/ts-logger';
const logger = new Logger({ timeStamps: true });
class ExampleClass {
@logger.decorate(LOG_LEVEL.INFO, { executionTime: true })
public exampleMethod(a: number, b: number): number {
return a + b;
}
}
const example = new ExampleClass();
example.exampleMethod(1, 2);
/*
Output: [2022-01-01 00:00:00] [exampleMethod] {
args: [1, 2],
returns: 3,
executionTime: 3ms
}
*/- executionTime (Boolean): Whether to calculate and print the function execution time. (default: false)
This library provides a few built-in log handlers that can be used out of the box:
- Console handler: This handler outputs log messages to the console.
- File handler: This handler writes log messages to a file on disk.
- JSON handler: This handler outputs log messages in JSON format, which can be easily processed by other systems.
Here's an example of how to use the built-in log handlers:
import { Logger, ConsoleHandler, FileHandler, JsonHandler } from '@origranot/ts-logger';
// Create an instance of the console logger
const consoleHandler = new ConsoleHandler();
// Create an instance of the JSON logger
const jsonHandler = new JsonHandler();
/*
Note: The file handler will create the file if it doesn't exist, and append to it if it does.
We can also provide log rotation options to the file handler, which will automatically
rotate the log file according to the date.
*/
const fileHandler = new FileHandler({ path: 'logs/app.log'});
const logger = new Logger({
timeStamps: true
handlers: [consoleHandler, jsonHandler, fileHandler]
});
/*
Log messages will be handled by all three handlers:
- The console handler will output the log message to the console.
- The JSON handler will output the log message to the console in JSON format.
- The file handler will write the log message to the file.
*/
logger.info('Application started');Note that you can add multiple handlers to a single logger, so that log messages can be sent to multiple outputs. You can also create custom log handlers by implementing the LogHandler interface as shown below:
import { Logger, HandlerPayload } from '@origranot/ts-logger';
export class CustomHandler implements LogHandler {
handle(payload: HandlerPayload) {
console.log(`[${payload.timestamp}] - ${payload.message}`);
}
}Contributions are welcome! For feature requests and bug reports, please open an issue.