Page updated Jan 16, 2024

Console Logger

AWS Amplify writes console logs through Logger. You can use Logger in your apps for the same purpose.

Installation

Import Logger:

import { Logger } from 'aws-amplify';
1import { Logger } from 'aws-amplify';

Working with the API

You can call logger for different console message modes:

const logger = new Logger('foo'); logger.info('info bar'); logger.debug('debug bar'); logger.warn('warn bar'); logger.error('error bar');
1const logger = new Logger('foo');
2
3logger.info('info bar');
4logger.debug('debug bar');
5logger.warn('warn bar');
6logger.error('error bar');

When handling an error:

try { // ... } catch(e) { logger.error('error happened', e); }
1try {
2 // ...
3} catch(e) {
4 logger.error('error happened', e);
5}

Setting Logging Levels

You can set a log level when you create your logger instance:

const logger = new Logger('foo', 'INFO'); logger.debug('callback data', data); // this will not write the message
1const logger = new Logger('foo', 'INFO');
2
3logger.debug('callback data', data); // this will not write the message

Global logger configuration will override your logger instance's configuration:

Amplify.Logger.LOG_LEVEL = 'DEBUG'; const logger = new Logger('foo', 'INFO'); logger.debug('callback data', data); // this will write the message since the global log level is 'DEBUG'
1Amplify.Logger.LOG_LEVEL = 'DEBUG';
2
3const logger = new Logger('foo', 'INFO');
4
5logger.debug('callback data', data); // this will write the message since the global log level is 'DEBUG'

During web development, you can set global log level in browser console log:

window.LOG_LEVEL = 'DEBUG';
1window.LOG_LEVEL = 'DEBUG';

Supported log levels:

  • ERROR
  • WARN
  • INFO
  • DEBUG
  • VERBOSE