85132 - BugZilla should check/auto-correct new attachment MIME types

Status: NEW

(Bugzilla :: Attachments & Requests, enhancement, P5)

Description

[Roland Mainz]

BugZilla's attachment code should support compressed content. There should be a
dropdown/checkbox to indicate that the attached file is mimetype=xyz and
compressed via compress/gzip/etc.

BugZilla should _verify_ that the attached content is really compressed and
return an error if it cannot find the matching magic numbers (see /etc/magic and
file(1)) for compress/gzip/etc. in the incoming upload stream...

Comment 1

[Roland Mainz]

Oh... I forgot the comment "why":

Why:
The browser should be able to decompress the file on-the-fly...

Comment 2

[Andreas Franke (gone)]

reassigning to default owner.

Comment 3

[Gervase Markham [:gerv]]

This is so not worth doing :-) It's useful only for testing on-the-fly
decompression in Mozilla - and you can set up your own webserver for that.
There's no real benefit to Bugzilla in doing this, given that not all browsers
support on-the-fly decompression, so we'd need to sniff etc. etc.

Gerv

Comment 4

[jay ball]

i'm going to agree with gerv, this is not worth it.  

there are 852 bugs for bugzilla with milestone 1.18 or future, marking this as
WONTFIX will save the bugzilla team 0.12% of the effort to close all of these
bugs.  :)

Comment 5

[Myk Melez [:myk] [@mykmelez]]

Jay, please don't set the "approval" flag.  That flag is only for project
maintainers to say in whether patches to fix bugs can get checked in.

There is some value to compression.  Compressed attachments transfer much more
quickly over the wire and take up less space in the database, and since
attachments are the number one database hog on b.m.o, anything that improves the
situation is welcome.

On the other hand, Bugzilla already supports compression in that it accepts
compressed attachments and returns them in the same compressed format.  Also,
users shouldn't have to deal with compression themselves; Bugzilla should take
care of it for them.  This bug needs clarification:

BugZilla's attachment code should support compressed content -- FIXED
There should be a dropdown/checkbox to indicate that the attached file is
mimetype=xyz and compressed via compress/gzip/etc. -- WONTFIX (Bugzilla should
be able to figure this out without having to ask the user)

BugZilla should _verify_ that the attached content is really compressed and
return an error if it cannot find the matching magic numbers (see /etc/magic and
file(1)) for compress/gzip/etc. in the incoming upload stream. -- NEW, but
Bugzilla should trust that the user knows what they want to do and throw only a
warning or just change the MIME type to the correct one if it knows what it is;
plus this is useful for files in general, not just compressed content

Since only one issue remains (checking/auto-correcting MIME types), I'm going to
morph this bug to deal with it.  It's not clear that we can use file(1) and
magic for this; on my system at least that mechanism stores human-readable
descriptions of file types without any clear MIME type mapping.

Note also bug 157237 about compressed attachments.

Comment 6

[Daniel Berlin]

Myk, You must be looking at /etc/magic rather than /etc/magic.mime (or
/usr/share/magic.mime).

File::MMagic, which is the module that guesses mime types using magic files, has
a magic.mime internally pasted into it that it can use (of course, I think this
is a horrible idea, since they have bugs, and get updated often, so the internal
one is always out of date and more buggy than what is on someone's system, and
it *defaults* to using the internal one, rather than as a fallback).


It's trivial to use the module, however. This bug would take a whole of 3.6
minutes to fix. :)
I had been using File::MMagic in both my gnats2bz.pl rewrite, and a similar
python module  in the python rewrite. 

Comment 7

[Dave Miller [:justdave]]

Hmm...  we could do something along the lines of "your browser told us the file
you sent was 'text/plain' but the content of the file seems to look like it
should be 'text/html'.  If your browser was wrong, please go fix the attachment
type (with a link) or something to that effect.  Or maybe even a link that just
goes and does it.