Retrieve a Request’s IP Address in Node.js

Web frameworks in Node.js provide a request object containing information from the requesting instance. The request object typically includes the IP address of the requesting client. If you want to geo-locate the requesting user, the IP address is helpful.

This tutorial shows you how to retrieve the client IP address from a request instance in Node.js.

Node.js Series Overview

  1. String Replace All Appearances
  2. Remove All Whitespace From a String in JavaScript
  3. Generate a Random ID or String in Node.js or JavaScript
  4. Remove Extra Spaces From a String in JavaScript or Node.js
  5. Remove Numbers From a String in JavaScript or Node.js
  6. Get the Part Before a Character in a String in JavaScript or Node.js
  7. Get the Part After a Character in a String in JavaScript or Node.js
  8. How to Check if a Value is a String in JavaScript or Node.js
  9. Check If a String Includes All Strings in JavaScript/Node.js/TypeScript
  10. Check if a Value is a String in JavaScript and Node.js
  11. Limit and Truncate a String to a Given Length in JavaScript and Node.js
  12. Split a String into a List of Characters in JavaScript and Node.js
  13. How to Generage a UUID in Node.js
  14. Reverse a String in JavaScript or Node.js
  15. Split a String into a List of Lines in JavaScript or Node.js
  16. Split a String into a List of Words in JavaScript or Node.js
  17. Detect if a String is in camelCase Format in Javascript or Node.js
  18. Check If a String Is in Lowercase in JavaScript or Node.js
  19. Check If a String is in Uppercase in JavaScript or Node.js
  20. Get the Part After First Occurrence in a String in JavaScript or Node.js
  21. Get the Part Before First Occurrence in a String in JavaScript or Node.js
  22. Get the Part Before Last Occurrence in a String in JavaScript or Node.js
  23. Get the Part After Last Occurrence in a String in JavaScript or Node.js
  24. How to Count Words in a File
  25. How to Shuffle the Characters of a String in JavaScript or Node.js
  26. Append Characters or Words to a String in JavaScript or Node.js
  27. Check if a String is Empty in JavaScript or Node.js
  28. Ensure a String Ends with a Given Character in JavaScript or Node.js
  29. Left-Trim Characters Off a String in JavaScript or Node.js
  30. Right-Trim Characters Off a String in JavaScript or Node.js
  31. Lowercase the First Character of a String in JavaScript or Node.js
  32. Uppercase the First Character of a String in JavaScript or Node.js
  33. Prepend Characters or Words to a String in JavaScript or Node.js
  34. Check if a String is a Number
  35. Convert a String to Buffer
  36. Prevent Line Breaks in String Template Literals
  37. How to Implement a Custom `toString` Method (Coming soon)
  38. What Is `Symbol.toStringTag` and How to Use It (Coming soon)

Get the Request IP Address

The request can carry the client’s IP address in different locations. For example, it may be stored in an HTTP request header like x-forwarded-for, in one of the request properties like request.connection, request.socket, request.info, or request.raw.

Serverless environments provide a request context. For example, in AWS Lambda functions using AWS API Gateway you may have the IP address stored in an identity property carrying the sourceIp.

The @supercharge/request-ip package streamlines the process retrieving the request’s IP address. It checks dozens of possible locations and returns the found IP address.

At first, install the package as a dependency of your project:

npm install @supercharge/request-ip  

Then, go ahead and retrieve IP address from the request object like this:

const RequestIp = require('@supercharge/request-ip')

const ip = RequestIp.getClientIp(request)

// for example '213.211.254.97' as an IP v4 address
// or '2001:0db8:85a3:0000:0000:8a2e:0370:7334' as an IP v6 address
// or 'undefined' if no IP address is available on the given request

That’s it. Pass the request object to the RequestIp.getClientIp(request) function and it returns the IP address (or undefined if nothing was found).

Detect the IP Address in Frameworks Like Express/hapi/Fastify/Koa/Co.

Depending on your web framework of choice and use case, you may need to retrieve the IP address in a middleware or route handler.

Here are two basic examples showing how to retrieve the IP address in an Express middleware and hapi route handler:

simple Express middleware example

const RequestIp = require('@supercharge/request-ip')

const expressMiddleware = function (req, res, next) {  
  req.ip = RequestIp.getClientIp(req)

  next()
}

simple hapi route handler example:

const Hapi = require('@hapi/hapi')  
const RequestIp = require('@supercharge/request-ip')

const server = new Hapi.Server({  
  host: 'localhost'
})

server.route({  
  method: 'GET',
  path: '/login',
  handler: (request, h) => {
    const ip = RequestIp.getClientIp(request)

    return h.response(ip)
  }
})

The @supercharge/request-ip package comes handy when retrieving a client’s IP address from a request instance!


Mentioned Resources

Explore the Library

Find interesting tutorials and solutions for your problems.