finding file by size

[Mark Janes]

Carl Worth <cworth at cworth.org> writes:

> On Tue, Nov 06 2018, Ralph Seichter wrote:
>> I'm not sure about using Notmuch itself,
>
> Right. Notmuch doesn't currently index (as far as I'm aware) anything
> that would be useful for sorting by size.
>
>> but this should work:
>>
>>   find /path/to/maildir -type f -size +50M | xargs rm
>
> Hmm... I imagine that Mark would be more interested in viewing these
> files to ensure they are what he thinks they are before deleting them.

Yes, exactly this.  It's quite nice to see the messages in question.
Looking at the raw message files is not helpful, as the contents are
usually encoded.

> So, capturing the results of that with a notmuch tag would be
> a reasonable thing to do. The only trick there is that I don't see any
> existing search term to find a message associated with a particular file
> name, (we have "path:" and "folder:" to find messages in a specific
> directory, but nothing I see for finding the message corresponding to a
> specific file).

It would be better to have a separate numeric field in xapian similar to
how the date is handled.  Then the user could search for files of
specific sizes.  A more usable feature would be to sort the currently
selected messages by size in emacs or any other front-end.

In the past I've used Thunderbird to archive old/large messages from my
imap server.  It has a column in the UI that allows you to sort files by
size.  I'm just now realizing that notmuch *only* sorts messages by date
(at least in emacs) -- and I haven't missed any other sort functionality
until now...

> So, then we could extract the message-id from each file and do a search
> based on that I guess?
>
> Here's a (bash) command I just ran on my mail store of over a million
> messages that tagged the 8 messages larger than 50MB. It took about a
> minute to run (with a warm cache):
>
>   for msg in $(
>                for file in $(find . -type f -size +50M);
>                do
>                  grep -i ^Message-Id $file | sed -e 's/^.*<\(.*\)>.*/\1/';
>                done
>              );
>   do
>     notmuch tag +large id:$msg;
>   done
>
> With that, I'm able to go through the list from:
>
>   notmuch search tag:large
>
> to investigate whether these large emails are worth keeping.
>
> So, that's obviously not extremely elegant, but it's at least possible.

Thanks for this, I will use your command for my current needs.  Even if
notmuch supported a more elegant feature, I would still need to somehow
locate and remove the messages from my maildir.  I can see how the
separation between the xapian database and the maildir makes it
impossible to support cleaning up the maildir through notmuch.