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[[!meta title="Use Internet Protocol Translators (ftpfs etc.) as Backends for Other Programs"]]

The Hurd design facilitates splitting up large applications into independent,
generic components, which can be easily combined in different contexts, by
moving common functionality into separate Hurd servers (translators),
accessible trough filesystem interfaces and/or specialized RPC interfaces.

Download protocols like FTP, HTTP, BitTorrent etc. are very good candidates for
this kind of modularization: a program could simply use the download
functionality by accessing FTP, HTTP etc. translators.

There is already an [[hurd/translator/ftpfs]] translator in the Hurd tree, as
well as an [[hurd/translator/httpfs]] on
[hurdextras](http://www.nongnu.org/hurdextras/); however,
these are only suitable for very simple use cases: they just provide the actual
file contents downloaded from the URL, but no additional status information
that are necessary for interactive use. (Progress indication, error codes, HTTP
redirects etc.)

A new interface providing all this additional information (either as an
extension to the existing translators, or as distinct translators) is required
to make such translators usable as backends for programs like apt for
example.

The goal of this project is to design a suitable interface, implement it for at
least one download protocol, and adapt apt (or some other program) to use
this as a backend.

This task requires some design skills and some knowledge of internet protocols,
to create a suitable interface. Translator programming knowledge will have to
be obtained while implementing it.

It is not an easy task, but it shouldn't pose any really hard problems either.

Possible mentors: Olaf Buddenhagen (antrik)

Exercise: Make some improvement to one of the existing download translators --
httpfs in particular is known to be buggy.