id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	launchpad_bug
994	support precompressed files	davidsarah	somebody	"A ""precompressed file"" is a file where the plaintext has been compressed using an algorithm supported by HTTP (gzip or deflate -- we'd probably support only one). When the file is served via the webapi, it is served in compressed form with the [http://tools.ietf.org/html/rfc2616#section-14.11 Content-Encoding] HTTP header set appropriately. The Content-Encoding can also be set in a PUT or POST request to upload a precompressed file.

Storage servers would be completely ignorant of precompressed files. The CLI, SFTP and FTP frontends would have to be decompress them. The gateway would also have to decompress if it receives an HTTP request that does not have an [http://tools.ietf.org/html/rfc2616#section-14.3 Accept-Encoding] header allowing the compression algorithm used for that file.

This would provide a performance improvement as long as the HTTP clients have sufficient CPU capacity, that the time taken for them to decompress is outweighed by the savings in bandwidth. CPU-constrained clients (connecting to a less CPU-constrained gateway) are not a problem because they can just not set {{{Accept-Encoding}}}.

This would rely on HTTP clients implementing decompression correctly; if they don't then there is a potential loss of integrity, and the possibility of attacks against the client from maliciously constructed compressed data. It is possible to protect against ""decompression bombs"" if that is required."	enhancement	new	major	undecided	code	1.6.0		compression space-efficiency performance bandwidth security integrity backward-compatibility