Serverless-es-logger NPM

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"
  }
}