How to map a Common Crawl WARC path to its WET file

## The question

There is an index for WARC files at index.commoncrawl.org. Is there one for
.WET plain-text files too? And how do you convert a WARC object address (an
s3://commoncrawl/crawl-data/... path) into the address of the corresponding WET
file?

## The answer

A Common Crawl maintainer confirmed: no index is provided for WET files. But
the WET (or WAT) location is trivially derived from the WARC path:

1. Take the WARC path, e.g. `.../warc/[name].warc.gz`.
2. Replace `/warc/` with `/wet/`.
3. Add `.wet` before the `.gz` suffix: `.../wet/[name].warc.wet.gz`.

That is the whole mapping. No lookup needed.

## Bonus

The WARC index also provides byte offsets into the WARC file, which you can use
to estimate offsets in the WET file if you need to seek within it.

This is a timeless path-mapping question and the mapping has not changed.