How can I retrieve a user's public IP address via Amazon API Gateway + Lambda (node)

node.js amazon-web-services aws-lambda aws-api-gateway
rdegges picture rdegges · Oct 11, 2015 · Viewed 34.5k times · Source

I'm currently writing a Node.js lambda function, in which I want to log the incoming requester's public IP address. I've been looking through both the API Gateway and Lambda docs all day, but haven't found a solution.

Does the lambda event object include request metadata I can use to extract the user's IP?

Answer

Jonathan picture Jonathan · Sep 3, 2017

Update for HTTP APIs

Adding @Elijah's comment. The format for HTTP APIs will be

event['requestContext']['http']['sourceIp']

Edit

A better way is actually to check

event['requestContext']['identity']['sourceIp']

You can also get the User-Agent from the same object

event['requestContext']['identity']['userAgent']

See Cesar's comment below. Headers are easily spoofed and the user can set X-Forwarded-For to anything. AFAIK the sourceIp above is retrieved from the TCP connection.

Original answer

As of September 2017, you can create a method in API Gateway with Lambda Proxy integration, this will give you access to

events['headers']['X-Forwarded-For']

Which will look something like 1.1.1.1,214.25.52.1

The first ip 1.1.1.1 is your user's public ip address.

Related questions

Can an AWS Lambda function call another

I have 2 Lambda functions - one that produces a quote and one that turns a quote into an order. I'd like the Order lambda function to call the Quote function to regenerate the quote, rather than just receive it from …

Read More
AWS lambda api gateway error "Malformed Lambda proxy response"

I am trying to set up a hello world example with AWS lambda and serving it through api gateway. I clicked the "Create a Lambda Function", which set up the api gatway and selected the Blank Function option. I added …

Read More
Why is this HTTP request not working on AWS Lambda?

I'm getting started with AWS Lambda and I'm trying to request an external service from my handler function. According to this answer, HTTP requests should work just fine, and I haven't found any documentation that says otherwise. (In fact, people …

Read More