@carloshatus/to_log

toLog

A small lib to organize logs at your service, compatible with AWS Lambda logging and AWS CloudWatch logs.

Fast start

install

npm

npm i @carloshatus/to_log

yarn

yarn add @carloshatus/to_log

import

import { ToLog } from '@carloshatus/to_log';

instance

const log = new ToLog('your:log');

logging

log.info('this is a info log');
// console mode
// [INFO] this is a info log
 
// debug mode
// app:your:log [INFO] this is a info log
 
log.warn('this is a warning log');
// console mode
// [WARN] this is a warning log
 
// debug mode
// app:your:log [WARN] this is a warning log
 
log.error('this is a error log');
// console mode
// [ERROR] this is a error log
 
// debug mode
// app:your:log [ERROR] this is a error log

data on log

log.info('this is a info log with data:', { value: 'data' });
// console mode
// [INFO] this is a info log with data: {"value":"data"}
 
// debug mode
// app:your:log [INFO] this is a info log with data: {"value":"data"}
 
log.warn('this is a warning log with data:', { value: 'data' });
// console mode
// [WARN] this is a warning log with data: {"value":"data"}
 
// debug mode
// app:your:log [WARN] this is a warning log with data: {"value":"data"}
 
log.error('this is a error log with data:', { value: 'data' });
// console mode
// [ERROR] this is a error log with data: {"value":"data"}
 
// debug mode
// app:your:log [ERROR] this is a error log with data: {"value":"data"}

API Reference

constructor

new ToLog(identifier, appPrefix);

create a new instance of ToLog object.

• identifier [String]: name for your debug log;
• appPrefix [String, default: 'app']: prefix to better identify your application in the debug log;

log functions

info

log.info(message, data);

log a info message.

• message [String]: message to your log;
• data [Any, default: 'null']: complement of your log, it is automatically parsed to string;

Note: if occurred a problem on parse the data to string, the error message is returned on data place.

E.g.

// console mode

[INFO] this is a info log with data: [UnexpectedJSONParseError]: Converting circular structure to JSON

// debug mode

app:your:log [INFO] this is a info log with data: [UnexpectedJSONParseError]: Converting circular structure to JSON

warn

log.warn(message, data);

log a warning message.

• message [String]: message to your log;
• data [Any, default: 'null']: complement of your log, it is automatically parsed to string;

Note: if occurred a problem on parse the data to string, the error message is returned on data place.

E.g.

// console mode

[INFO] this is a info log with data: [UnexpectedJSONParseError]: Converting circular structure to JSON

// debug mode

app:your:log [INFO] this is a info log with data: [UnexpectedJSONParseError]: Converting circular structure to JSON

error

log.error(message, data);

log a error message.

• message [String]: message to your log;
• data [Any, default: 'null']: complement of your log, it is automatically parsed to string;

Note: if occurred a problem on parse the data to string, the error message is returned on data place.

E.g.

// console mode

[INFO] this is a info log with data: [UnexpectedJSONParseError]: Converting circular structure to JSON

// debug mode

app:your:log [INFO] this is a info log with data: [UnexpectedJSONParseError]: Converting circular structure to JSON

log mode

The default log mode is console mode. To use the debug mode, start your app with the node environment variable DEBUG.

DEBUG=app:* node index.js
DEBUG=your_app_prefix:* node index.js