Symbolic links inside .deb pulled as directories

[Michael Berger]

I have a Debian package that installs a library and a symbolic link to the library. The symlinks end up being installed as empty directories. I would expect symlinks to be preserved.

I'm using snapcraft version 2.19.

As an example/repro, take the package libgweather.

It installs a library and symlink to the library.

mberger@bldecos-1:/var/cache/apt/archives$ dpkg -c libgweather-3-6_3.18.2-0ubuntu0.1_amd64.deb | grep "\.so"
-rw-r--r-- root/root 153808 2016-09-14 08:27 ./usr/lib/x86_64-linux-gnu/libgweather-3.so.6.5.0
lrwxrwxrwx root/root 0 2016-09-14 08:27 ./usr/lib/x86_64-linux-gnu/libgweather-3.so.6 -> libgweather-3.so.6.5.0

The relevant snapcraft.yaml parts entry...

parts:
  my-part:
    # See 'snapcraft plugins'
    plugin: dump
    source: /var/cache/apt/archives/libgweather-3-6_3.18.2-0ubuntu0.1_amd64.deb

The result of the pull...

mberger@bldecos-1:/builds2/mberger/bug$ ls -l parts/my-part/src/usr/lib/x86_64-linux-gnu/
total 156
drwxr-xr-x 2 mberger xcore 4096 Oct 19 05:31 libgweather-3.so.6
-rw-r--r-- 1 mberger xcore 153808 Sep 14 08:27 libgweather-3.so.6.5.0

Which finds its way into the snap.

mberger@bldecos-1:/builds2/mberger/bug$ unsquashfs -ll my-snap-name_0.1_amd64.snap
Parallel unsquashfs: Using 4 processors
56 inodes (400 blocks) to write
...
drwxr-xr-x root/root 3 2016-10-19 05:31 squashfs-root/usr/lib/x86_64-linux-gnu/libgweather-3.so.6
-rw-r--r-- root/root 153808 2016-09-14 08:27 squashfs-root/usr/lib/x86_64-linux-gnu/libgweather-3.so.6.5.0
...

[Loïc Minier (lool)]

I can repro the issue with snapcraft 2.19

[Kyle Fazzari (kyrofa)]

This seems to be an issue with python3-apt. The proposed fix is to use python3-debian instead: https://github.com/snapcore/snapcraft/pull/941