---
categories:
  - DevOps
tags: [AWS, aws-lambda, backend]
---

# AWS Lambda examples

## Reconstruct CloudFront URLs

```js
exports.handler = (event, context, callback) => {
  // Extract the request from the CloudFront event that is sent to Lambda@Edge
  var request = event.Records[0].cf.request;

  // Extract the URI from the request
  var olduri = request.uri;

  // Match any '/' that occurs at the end of a URI. Replace it with a default index
  var newuri = olduri.replace(/\/$/, "/index.html");

  // Replace the received URI with the URI that includes the index page
  request.uri = newuri;

  // Return to CloudFront
  return callback(null, request);
};
```