winston-cloudwatch v1.3.1

Send logs to Amazon Cloudwatch using Winston.

Features

• logging to AWS CloudWatchLogs
• logging to multiple streams
• logging with multiple levels
• creates group / stream if they don't exist
• doesn't try to buffer your unsent logs (you should use more streams)
• see options for more
• 100% code coverage in lib layer (WIP for the rest)

Installing

$ npm install --save winston winston-cloudwatch

Configuring

AWS configuration works using ~/.aws/credentials as written in AWS JavaScript SDK guide.

As specified in the docs:

The AWS SDK for Node.js doesn't select the region by default.

so you should take care of that. See the examples below.

If either the group or the stream do not exist they will be created for you.

For displaying time you should click on the gear in the top right corner on page with your logs and enable checkbox "Creation Time".

Usage

Please refer to AWS CloudWatch Logs documentation for possible contraints that might affect you. Also have a look at AWS CloudWatch Logs limits.

var winston = require('winston'),
    WinstonCloudWatch = require('../index');

winston.add(WinstonCloudWatch, {
  logGroupName: 'testing',
  logStreamName: 'first'
});

winston.error('1');

You could also log to multiple streams with / without different log levels, have a look at this example.

Options

This is the list of options you could pass as argument to winston.add:

• level - defaults to info
• logGroupName
• logStreamName
• awsAccessKeyId
• awsSecretKey
• awsRegion
• jsonMessage - boolean, format the message as JSON
• messageFormatter - function, format the message the way you like. This function will receive a log object that has the following properties: level, msg, and meta, which are passed by winston to the log function (see CustomLogger.prototype.log as an example)
• proxyServer - String, use proxyServer as proxy in httpOptions
• uploadRate - Number, how often logs have to be sent to AWS. Be careful of not hitting AWS CloudWatch Logs limits, the default is 2000ms.
• errorHandler - function, invoked with an error object, if not provided the error is sent to console.error

AWS keys are usually picked by aws-sdk so you don't have to specify them, I provided the option just in case. Remember that awsRegion should still be set if you're using IAM roles.

Please refer to the provided examples for more hints.