@travel-cloud/simple-lambda-logger

simple-lambda-logger

Simple logging solution for Node.js AWS Lambda projects that supports multiple logging levels as well as optional support to send logs to third parties.

Usage

npm i @travel-cloud/simple-lambda-logger

Logging creation reads an ENV property to create a logger at the desired level, you can set this in AWS by simply setting the property as part of your configuration.

process.env.LOG_LEVEL = 'DEBUG';

const logger = require('@travel-cloud/simple-lambda-logger');

mylogger = logger.newLogger();

mylogger.debug('Your logs');

If logs are logged in JSON format like so:

mylogger.debug({
    foo: 'bar',
  }));

Then they are sent to the console as a stringified JSON object without a timestamp.

By default logs are sent to the console in the format:

'${timestamp} ${level} ${log}'

Then

Any calls to log against a logger of a higher level resolve to an empty function and are ignored. For example the following has no effect:

process.env.LOG_LEVEL = 'ERROR';
const logger = require('@travel-cloud/simple-lambda-logger');

mylogger = logger.newLogger();

mylogger.debug('Your logs');

Levels

1. DEBUG
2. INFO
3. ERROR

If no level property is specified or an unknown value is configured this will result in an error level logger being created.

Third Parties

logentries.com

The previous logentries support has been causing some performance issues within AWS lambda. We have removed logentries support from this version while we take some time to further investigate. If you would like to continue using logentries with simple-lambda-logger please use v1.1.3

Close

Usage of a third party logger in AWS Lambda requires you to close the simple logger. Failure to do so will most likely result in the function timing out as chances are the third party library is keeping its connection open. Using the simple logger you simply call close before the end of your lambda function:

process.env.LOG_LEVEL = 'DEBUG';
const logger = require('@travel-cloud/simple-lambda-logger');
mylogger = logger.newLogger();
mylogger.debug('Your logs');
// terminate the logger
await mylogger.close();
//end the lambda function according to your requirements eg
callback(null, response);

Calling close returns a promise for you to await before terminating your lambda function, if the logger does not require closing a resolved promise is automatically returned.