datadog-lambda-js

What is datadog-lambda-js?

The datadog-lambda-js npm package is designed to help you monitor and trace your AWS Lambda functions with Datadog. It provides tools to automatically collect and send metrics, logs, and traces from your Lambda functions to Datadog, enabling you to gain insights into the performance and behavior of your serverless applications.

What are datadog-lambda-js's main functionalities?

Automatic Tracing

This feature allows you to automatically trace your Lambda function executions. By wrapping your handler with the `datadog` function, you can send traces to Datadog without manually instrumenting your code.

const { datadog } = require('datadog-lambda-js');

const handler = datadog(async (event, context) => {
  // Your Lambda function code here
  return { statusCode: 200, body: 'Hello, world!' };
});

module.exports.handler = handler;

Custom Metrics

This feature allows you to send custom metrics from your Lambda functions to Datadog. You can use the `sendDistributionMetric` function to send metrics with specific values and tags.

const { sendDistributionMetric } = require('datadog-lambda-js');

const handler = async (event, context) => {
  // Your Lambda function code here
  sendDistributionMetric('my_custom_metric', 42, 'tag:value');
  return { statusCode: 200, body: 'Hello, world!' };
};

module.exports.handler = handler;

Log Forwarding

This feature enables you to forward logs from your Lambda functions to Datadog. By wrapping your handler with the `datadog` function, logs generated within your Lambda function will be automatically sent to Datadog.

const { datadog } = require('datadog-lambda-js');

const handler = datadog(async (event, context) => {
  console.log('This is a log message');
  return { statusCode: 200, body: 'Hello, world!' };
});

module.exports.handler = handler;

Other packages similar to datadog-lambda-js

aws-xray-sdk

The aws-xray-sdk package is an AWS service that provides tracing capabilities for AWS Lambda functions. It allows you to trace requests as they travel through your entire application, including Lambda functions, and visualize the trace data in the AWS X-Ray console. While it offers tracing similar to datadog-lambda-js, it is specific to the AWS ecosystem and does not provide the same level of integration with Datadog.

serverless-plugin-datadog

The serverless-plugin-datadog package is a Serverless Framework plugin that automatically instruments your Lambda functions with Datadog. It provides similar functionality to datadog-lambda-js but is designed to work within the Serverless Framework, making it easier to integrate Datadog monitoring into your serverless applications.

README

datadog-lambda-js

Datadog Lambda Library for Node.js enables enhanced Lambda metrics, distributed tracing, and custom metric submission from AWS Lambda functions.

Installation

Follow the installation instructions, and view your function's enhanced metrics, traces and logs in Datadog.

Custom Metrics

Once installed, you should be able to submit custom metrics from your Lambda function.

Check out the instructions for submitting custom metrics from AWS Lambda functions.

Tracing

Once installed, you should be able to view your function's traces in Datadog.

For additional details on trace collection, take a look at collecting traces from AWS Lambda functions.

For additional details on trace and log connection, check out the official documentation for Datadog trace client.

The fs module is disabled by default. If you want to enable it you have to set the environment variable DD_TRACE_DISABLED_PLUGINS to '' or to a comma-separated list of the plugins you want to disable. See the full list of supported plugins here.

Trace & Log Correlation

By default, the Datadog trace id gets automatically injected into the logs for correlation, if using console or a logging library supported for automatic trace id injection. You have to manually inject the trace id, if using other logging libraries. See additional details on connecting logs and traces.

Set the environment variable DD_LOGS_INJECTION to false to disable this feature.

Custom logger

You can use your own logger to log layer error and debug logs instead of default console usage.

For example, using the Pino logger:

const { datadog } = require("datadog-lambda-js");
const logger = require("pino")();

// convert message string to object metadata and message
const messageToObject = (stringMessage) => {
  const { message, status, ...metadata } = JSON.parse(stringMessage);

  return [metadata, message];
};

async function myHandler(event, context) {
  // ...
}

// Use your own logger
module.exports.myHandler = datadog(myHandler, {
  logger: {
    debug: (message) => logger.debug(...messageToObject(message)),
    error: (message) => logger.error(...messageToObject(message)),
  },
});

Environment Variables

DD_FLUSH_TO_LOG

Set to true (recommended) to send custom metrics asynchronously (with no added latency to your Lambda function executions) through CloudWatch Logs with the help of Datadog Forwarder. Defaults to false. If set to false, you also need to set DD_API_KEY and DD_SITE.

DD_API_KEY

If DD_FLUSH_TO_LOG is set to false (not recommended), the Datadog API Key must be defined by setting one of the following environment variables:

• DD_API_KEY - the Datadog API Key in plain-text, NOT recommended
• DD_KMS_API_KEY - the KMS-encrypted API Key, requires the kms:Decrypt permission

DD_SITE

If DD_FLUSH_TO_LOG is set to false (not recommended), and your data need to be sent to the Datadog EU site, you must set DD_SITE to datadoghq.eu. Defaults to datadoghq.com.

DD_LOG_LEVEL

Set to debug enable debug logs from the Datadog Lambda Library. Defaults to info.

DD_ENHANCED_METRICS

Generate enhanced Datadog Lambda integration metrics, such as, aws.lambda.enhanced.invocations and aws.lambda.enhanced.errors. Defaults to true.

DD_LAMBDA_HANDLER

Location of your original Lambda handler.

DD_TRACE_ENABLED

Initialize the Datadog tracer when set to true. Defaults to false.

DD_LOGS_INJECTION

Inject Datadog trace id into logs for correlation. Defaults to true.

DD_MERGE_XRAY_TRACES

Set to true to merge the X-Ray trace and the Datadog trace, when using both the X-Ray and Datadog tracing. Defaults to false.

Opening Issues

If you encounter a bug with this package, we want to hear about it. Before opening a new issue, search the existing issues to avoid duplicates.

When opening an issue, include the Datadog Lambda Layer version, Node version, and stack trace if available. In addition, include the steps to reproduce when appropriate.

You can also open an issue for a feature request.

Contributing

If you find an issue with this package and have a fix, please feel free to open a pull request following the procedures.

License

Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.

This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2019 Datadog, Inc.