Suggestions on mechanism or existing code - maintain persistence of file download history

[Dan Sommers]

On Thu, 30 Jan 2020 23:34:59 +1100
Chris Angelico <rosuav at gmail.com> wrote:

> ... I wasn't advocating for the use of a database; my first and
> strongest recommendation was, and still is, a stateless system wherein
> the files themselves are the entire indication of which documents have
> been downloaded.

Yes, I like stateless systems, too, but that system isn't stateless.  As
I understand the problem of a "crudely persistem download manager,"
there's a collection of to-be-downloaded URLs (which may be empty) and
some data that's been downloaded (which may also be empty).  You can
certainly encode a lot of that directly in the file system, but it's
still state.

Using a database instead solves a lot of the tricky bits that the bare
file system doesn't (which is what ChrisA said in what I snipped).  It's
just Greenspun's Tenth Rule with the words C, Fortran, and Common Lisp
crossed out and Python and ACID Database written in crayon.

Dan

-- 
“Atoms are not things.” – Werner Heisenberg
Dan Sommers, http://www.tombstonezero.net/dan