[RFC] LKML Archive in Maildir Format

[Eric Wong]

Bjorn Helgaas <bhelgaas at google.com> wrote:
> OK, so I understand how to clone archives from lore.kernel.org and how
> to convert a git archive to a maildir (thanks, Konstantin!)
> 
> What I *don't* understand is how to effectively read this locally.
> Ideally I'd like to run mutt, possibly with notmuch for indexing.  But
> a maildir with 3M files seems impractical.  I did actually try it
> (without notmuch), but it takes mutt about 5 minutes to start up.  And
> the maildir is about 23G, compared with 7.5G for the git archive.

Right, relying on Maildir for long-term storage of giant archives
is not a usable solution with any general purpose FSes I know about.
git itself had the same problem with loose object scalability in
the old days and packs were invented as a result.

> Any pointers?  I guess there's no mutt backend that can read a
> public-inbox archive directly?

There's mutt patches to support reading over NNTP, so that
works:

	mutt -f news://$INBOX_HOST/$INBOX_NEWSGROUP

I don't think mutt handles mboxrd 100% correctly, but it's close
enough that you can can download the gzipped mboxrd of a search
query and open it via "mutt -f /path/to/downloaded/mbox.gz"

  curl -XPOST -OJ "$INBOX_URL/?q=$SEARCH_QUERY&x=m"

POST is required(*), and -OJ lets it use the
Content-Disposition: header for a meaningful server-generated
name, but you can also redirect the result to whatever you want.

For all messages since March 1, you could use:

	SEARCH_QUERY=d:20190301..

All the supported search queries are documented in
$INBOX_URL/_/text/help/ and the search prefixes (e.g. "d:",
"s:", "b:") are modeled after what's in mairix.  You'll need to
escape the queries for URIs (e.g. " " => "+", and so on).
Xapian requires date ranges to be denoted with ".." whereas
mairix uses "-" for ranges.


The main thing public-inbox search misses from mairix is support
for "-t" which grabs non-matching messages from the same thread.
I would like to support that someday, but don't have enough time
(or funding) to make it happen at the moment.


(*) to reliably avoid wasting resources from spiders/prefetchers