serverless-es-logger

A simple logger for AWS Lambda that sends logs directly to Elasticsearch instead of Cloudwatch.

Features

• It's a Bunyan logger (see what it is supported here)
• Configurable via environment variables
• Auto attaches AWS Lambda environment variables such as AWS_REGION, AWS_LAMBDA_FUNCTION_NAME, STAGE, etc
• Works with the AWS Elasticsearch Service and other providers. Versions 6.x and 7.x are supported
• Compatible with Kibana (search, filter, aggregate and create dashboards with your log data)
• Integrates with @dazn/lambda-powertools-correlation-ids and auto attaches the existing CorrelationIds if the package is installed

Installation

With npm:

npm i --save serverless-es-logger

With yarn:

yarn add serverless-es-logger

Configuration via environment variables

Index configuration

ES_INDEX_TYPE: (optional) The type used for the indexed docs. default: _doc

ES_INDEX_PATTERN: (optional) The pattern used to create indexes in ES. default: logstash-YYYY.MM.DD

Connection configuration for the AWS Elasticsearch Service

ES_DOMAIN_ENDPOINT: (required) The domain's endpoint

ES_REGION: (optional) The AWS region where the domain is hosted. default: the current AWS_REGION

Connection configuration for other providers

ES_URI: (required) The Elasticsearch connection URI

Usage

Simple, just require and use it

const Log = require('serverless-es-logger')

Log.info({ message: 'This is a test' })

try {
  throw new Error('Something bad happened')
} catch (error) {
  Log.error({ err: error })
}

Notice that for errors the field err is recommended to be used so the error details are extracted and included in the log context.

Send messages like the following:

{
  "@timestamp": "2019-11-01T10:28:13.598Z",
  "message": "This is a test",
  "severity": "info",
  "fields": {
    "message": "This is a test"
  },
  "autofields": {
    "AWS_REGION": "us-east-1",
    "AWS_EXECUTION_ENV": "node10",
    "AWS_LAMBDA_FUNCTION_NAME": "my-function",
    "AWS_LAMBDA_FUNCTION_VERSION": "$LATEST",
    "AWS_LAMBDA_FUNCTION_MEMORY_SIZE": "1024",
    "STAGE": "dev"
  }
},
{
  "@timestamp": "2019-11-01T10:28:13.607Z",
  "message": "Something bad happened",
  "severity": "error",
  "fields": {
    "err": {
      "message": "Something bad happened",
      "name": "Error",
      "stack": "... the stack trace ..."
    }
  },
  "autofields": {
    "AWS_REGION": "us-east-1",
    "AWS_EXECUTION_ENV": "node10",
    "AWS_LAMBDA_FUNCTION_NAME": "my-function",
    "AWS_LAMBDA_FUNCTION_VERSION": "$LATEST",
    "AWS_LAMBDA_FUNCTION_MEMORY_SIZE": "1024",
    "STAGE": "dev"
  }
}

License

ISC © Carlos Castellanos