Re: Message-ID not found

[Kyle Meyer <kyle@kyleam.com>]

Mukund Sivaraman writes:

> I'm testing public-inbox with a "test-list" to try to provide a HTTP
> interface to mailing list archives. I'm using stock
> public-inbox-1.7.0-2.fc35.noarch on Fedora 35.
>
> List emails are injected by public-inbox-mda. public-inbox-httpd
> displays an error at this URL:
>
> https://inbox.banu.com/test-list/Yo1VM9+M%252FsYJIZkN@d1/T/

What's the source of this URL?  The slash looks percent-encoded one too
many times:

                  message ID: Yo1VM9+M/sYJIZkN@d1
                     |   /  -> %2F
                     V
        percent-encoded once: Yo1VM9+M%2FsYJIZkN@d1
                     |   %  -> %25
                     V
       percent-encoded twice: Yo1VM9+M%252FsYJIZkN@d1


> "Message-ID <Yo1VM9+M/sYJIZkN@d1/T> not found"

Hmm, I'm surprised by the trailing "/T".  When I visit the above URL, I
see

  Message-ID <Yo1VM9+M%2FsYJIZkN@d1>
  not found

which is what I would expect.

> The ASCII encoded Message-ID is "Yo1VM9+M/sYJIZkN@d1" generated by the
> Mutt client.
>
> The corresponding message exists:
> https://inbox.banu.com/test-list/Yo1VM9+M%2FsYJIZkN@d1/

Yes, the looks to match the URL you'd get by percent-encoding the "/"
once (see above).

> Could someone please check what the bug could be?
>
> Does public-inbox-httpd have a problem with the '/' character in
> Message-IDs?

Here's what https://inbox.banu.com/test-list/_/text/help/ says about
slashes:

  Forward slash ('/') characters in the Message-IDs
  need to be escaped as "%2F" (without quotes).

And here's the escaping that public-inbox does on the message ID
(<https://public-inbox.org/public-inbox.git/tree/lib/PublicInbox/MID.pm?h=v1.8.0#n130>):

  # RFC3986, section 3.3:
  sub MID_ESC () { '^A-Za-z0-9\-\._~!\$\&\'\(\)\*\+,;=:@' }
  sub mid_escape ($) { uri_escape_utf8($_[0], MID_ESC) }