Review the existing gateway cache
The gateway already uses/contains its own cache: Review that
These are outliers (We will almost certainly know the file-type suffix and it will at least be part of the pseudo-path):
We don't know that the granules stored in S3 will have object-ids that end in the correct/expected suffixes (that is, the suffixes that we use to determine file types).
We don't know that the CMR pseudo-paths will end in the correct suffix either.