bug#19439: guix download fails with "bad qstring header component"

bug#19439: guix download fails with "bad qstring header component"

[rekado]

In an attempt to build the OpenJDK tools with icepick, I'm getting an
error when downloading the icepick tarball:

~~~~~~~~~~~~~
$ ./pre-inst-env guix download http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz
starting download of `/tmp/guix-file.zrKNcT' from `http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz'...
ERROR: Bad qstring header component: 1200667312.0

failed to download "/tmp/guix-file.zrKNcT" from "http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz"
guix download: error: http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz: download failed
~~~~~~~~~~~~~

bug#19439: guix download fails with "bad qstring header component"

[Ludovic Courtès]

rekado <rekado@elephly.net> skribis:

> $ ./pre-inst-env guix download http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz
> starting download of `/tmp/guix-file.zrKNcT' from `http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz'...
> ERROR: Bad qstring header component: 1200667312.0

Indeed.  The HTTP headers here look like this:

--8<---------------cut here---------------start------------->8---
Date: Fri, 26 Dec 2014 22:10:49 GMT
Server: Apache/2.2.22 (Debian)
ETag: 1200667312.0
--8<---------------cut here---------------end--------------->8---

For details, this can be reproduced like this:

--8<---------------cut here---------------start------------->8---
scheme@(guile-user)> ,use(web client)
scheme@(guile-user)> (http-get "http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz")
web/http.scm:854:12: In procedure parse-entity-tag:
web/http.scm:854:12: Bad qstring header component: 1200667312.0


Entering a new prompt.  Type `,bt' for a backtrace or `,q' to continue.
scheme@(guile-user) [1]> ,bt
In web/client.scm:
    228:8  4 (request "http://icedtea.wildebeest.org/hg/icepick/archive/15425b469aea.tar.gz" #:body #f #:port #<input-output: s…> …)
In web/response.scm:
    199:6  3 (read-response #<input-output: socket 13>)
In web/http.scm:
   218:33  2 (lp ((server . "Apache/2.2.22 (Debian)") (date . #<date nanosecond: 0 second: 3 minute: 14 hour: 22 day: 26 mont…>)))
   188:11  1 (read-header #<input-output: socket 13>)
   854:12  0 (parse-entity-tag "1200667312.0")
--8<---------------cut here---------------end--------------->8---

And indeed, Section 14.19 of
<http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html> says that the
‘ETag’ header has type ‘entity-tag’.

‘parse-entity-tag’ is written like this:

--8<---------------cut here---------------start------------->8---
(define (parse-entity-tag val)
  (if (string-prefix? "W/" val)
      (cons (parse-qstring val 2) #f)
      (cons (parse-qstring val) #t)))
--8<---------------cut here---------------end--------------->8---

Section 3.11 at <http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html>
confirms the above definition for ‘entity-tag’.

Lastly, ‘quoted-string’ in
<http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html> is defined as a
string surrounded by double quotes, basically.

So, in short, I think Apache httpd is returning an invalid ETag header,
and Guile’s HTTP client is right in rejecting it.

Having said that doesn’t help much though.  I’m not sure how frequent
this is, and whether/how this could be worked around.  Ideas?

Thanks,
Ludo’.

bug#19439: guix download fails with "bad qstring header component"

[Eric Bavier]

I've encountered the same issue while attempting to upgrade the
python-pillow package.  For the newer versions 2.6.2 and 2.7.0, the
following errors are reported when downloading the source::

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
starting download of
`/gnu/store/i40q1mk9dnkg2mfyvfhjyq8lcywmgvh1-Pillow-2.7.0.tar.gz' from
`https://pypi.python.org/packages/source/P/Pillow/Pillow-2.7.0.tar.gz'...
ERROR: Bad qstring header component: 3fdc9f16a1b60366ae8158b424655d10

failed to download
"/gnu/store/i40q1mk9dnkg2mfyvfhjyq8lcywmgvh1-Pillow-2.7.0.tar.gz" from
"https://pypi.python.org/packages/source/P/Pillow/Pillow-2.7.0.tar.gz"
builder for
`/gnu/store/bij5w1kppj9wiqgarmsa3nc8z73i1v6l-Pillow-2.7.0.tar.gz.drv'
failed to produce output path
`/gnu/store/i40q1mk9dnkg2mfyvfhjyq8lcywmgvh1-Pillow-2.7.0.tar.gz'
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I don't have any ideas on how to work around this issue in general.  In
this case, we might be able to fetch the source from github rather than
pypi.  But this should add to the question of how frequent this problem
is.

-- 
Eric Bavier

bug#19439: guix download fails with "bad qstring header component"

[Ricardo Wurmus]

Eric Bavier writes:

> I've encountered the same issue while attempting to upgrade the
> python-pillow package.  For the newer versions 2.6.2 and 2.7.0, the
> following errors are reported when downloading the source::

[...]

> I don't have any ideas on how to work around this issue in general.  In
> this case, we might be able to fetch the source from github rather than
> pypi.  But this should add to the question of how frequent this problem
> is.

FWIW, pypi.python.org has been fixed after reporting the issue to the
webmasters.

Would it be desirable for the HTTP client to be a little more tolerant
in general?

~~ Ricardo