Bug#711707: devscripts: wnpp-check: Should support caching of downloaded data

[Axel Beckert]

Package: devscripts
Version: 2.13.2
Severity: wishlist
File: /usr/bin/wnpp-check

Dear Devscripts Maintainers,

wnpp-check currently seems to download the list of WNPP bugs on every
invocation, even if they follow very close to each other. This can be
annoying if you're just behind a thin/bad internet
connection. E.g. currently for me every invocation takes around 30
seconds due to just having a (not so good) EDGE connection.

According to its man-page, wnpp-alerts seems to already cache the
downloaded list of bugs. Can't wnpp-check use the same cache and maybe
even the same code to use it?

There are several ideas on how the cache could be used:

* Use If-Modified-Since or Expires
  headers. http://www.debian.org/devel/wnpp/being_packaged and
  http://www.debian.org/devel/wnpp/requested both have Expires as well
  as Last-Modified headers. That would likely be the optimal solution,
  maybe optionally disabled via a command-line switch.

* Make caching just an optional feature, e.g. by adding a command-line
  option to use the cache if present (or if older than N days or so).

-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (990, 'unstable'), (900, 'testing'), (899, 'testing-proposed-updates'), (600, 'stable'), (500, 'proposed-updates'), (200, 'experimental')
Architecture: i386 (i686)

Kernel: Linux 3.10-rc4-686-pae (SMP w/2 CPU cores)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages devscripts depends on:
ii  dpkg-dev  1.16.10
ii  libc6     2.17-5
ii  perl      5.14.2-21
ii  python3   3.2.3-7

Versions of packages devscripts recommends:
pn  at                        <none>
ii  curl                      7.30.0-2
ii  dctrl-tools               2.23
ii  debian-keyring            2013.04.21
ii  dput                      0.9.6.3+nmu2
ii  equivs                    2.0.9
ii  fakeroot                  1.19-2
ii  gnupg                     1.4.12-7
ii  libcrypt-ssleay-perl      0.58-1
ii  libdistro-info-perl       0.10
ii  libencode-locale-perl     1.03-1
ii  libjson-perl              2.58-1
ii  libparse-debcontrol-perl  2.005-4
ii  libsoap-lite-perl         0.714-1
ii  liburi-perl               1.60-1
ii  libwww-perl               6.04-1
ii  lintian                   2.5.13
ii  man-db                    2.6.3-7
ii  patch                     2.7.1-2
ii  patchutils                0.3.2-1.1
ii  python3-debian            0.1.21+nmu2
pn  python3-magic             <none>
ii  sensible-utils            0.0.9
ii  strace                    4.5.20-2.3
ii  unzip                     6.0-9
ii  wdiff                     1.1.2-1
ii  wget                      1.14-2
ii  xz-utils                  5.1.1alpha+20120614-2

Versions of packages devscripts suggests:
ii  build-essential              11.6
pn  cvs-buildpackage             <none>
ii  devscripts-el                35.4
ii  gnuplot                      4.6.3-2
ii  heirloom-mailx [mailx]       12.5-2
ii  libauthen-sasl-perl          2.1500-1
ii  libfile-desktopentry-perl    0.04-3
ii  libnet-smtp-ssl-perl         1.01-3
ii  libterm-size-perl            0.207-1
ii  libtimedate-perl             1.2000-1
ii  libyaml-syck-perl            1.27-1
ii  mutt                         1.5.21-6.2
ii  openssh-client [ssh-client]  1:6.2p2-4
pn  svn-buildpackage             <none>
ii  w3m                          0.5.3-8

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