Transform and replay CloudFront, ELB Classic, and ALB logs.

Usage no npm install needed!

<script type="module">
  import awsLogReplay from '';



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Transform and replay a stream of AWS CloudFront, ELB Classic, or ALB logs. You can use s3scan to easily stream logs into these tools.

This project uses the AWS JavaScript SDK: you will need to configure your own credentials.


Takes different types of logs as input and streams only the path to stdout. Supported types include "cloudfront" for CloudFront logs and "lb" for ELB Classic or ALB logs.

Usage: generatepath <type>


Makes replay requests to the baseurl. Expects paths to be piped to stdin. (Optional) Control concurrency of replay requests with --concurrency flag. Default is 100.

Usage: pathreplay <baseurl> [--concurrency=<n>]


Emits a repeatable set of input lines piped to stdin at a given sampling rate. The number of lines emitted will approach the specific rate over sufficiently large samples, but may diverge for small sample sizes. Sampling rates should be specified as a decimal number between zero and one. Optionally accepts a filter argument that restricts the sampled set to lines matching the specified regular expression.

Usage: sample --rate=<rate> [--filter=<filter>]