Add a "slim" variant. Fixes #2

.gitignore

@@ -1 +1,2 @@
 /rootfs
+/rootfs-slim

build.sh

@@ -39,3 +39,32 @@ if test $SUITE = stable; then
     docker tag  $IMAGE:$SUITE $IMAGE
     docker push $IMAGE
 fi
+
+docker run --rm \
+       --cap-add SYS_ADMIN \
+       --volume $PWD:/devuan \
+       --workdir /devuan \
+       $IMAGE ./trim.sh $SUITE $ROOTFS
+
+IMAGE=$CI_REGISTRY_IMAGE/slim
+STAMP=$(date +%F)
+
+cat > Dockerfile <<EOF
+FROM scratch
+ADD $ROOTFS-slim.tar.gz /
+CMD ["bash"]
+EOF
+
+docker build -t $IMAGE:$STAMP .
+
+ALIAS=$(docker run --rm $IMAGE:$STAMP cat /etc/devuan_version)
+
+docker push $IMAGE:$STAMP
+docker tag  $IMAGE:$STAMP $IMAGE:$ALIAS
+docker push $IMAGE:$ALIAS
+docker tag  $IMAGE:$ALIAS $IMAGE:$SUITE
+docker push $IMAGE:$SUITE
+if test $SUITE = stable; then
+    docker tag  $IMAGE:$SUITE $IMAGE
+    docker push $IMAGE
+fi

scripts-slim/tweak-apt-config

@@ -0,0 +1,23 @@
+#!/bin/sh -eu
+# tweak-apt-config -- for use in a Docker image
+# Copyright (C) 2017  Olaf Meeuwissen
+#
+# License: GPL-3.0+
+
+DIR=/
+ETC=etc/apt
+PARTS=apt.conf.d
+
+eval $(apt-config shell DIR Dir)
+eval $(apt-config shell ETC Dir::Etc)
+eval $(apt-config shell PARTS Dir::Etc::Parts)
+
+cfg=$DIR$ETC$PARTS
+
+cat > $cfg/docker-recommends <<EOF
+APT::Install-Recommends "false";
+APT::AutoRemove::RecommendsImportant "false";
+EOF
+chmod 0644 $cfg/docker-recommends
+
+rm $0

scripts-slim/tweak-dpkg-config

@@ -0,0 +1,37 @@
+#!/bin/sh -eu
+# tweak-dpkg-config -- for use in a Docker image
+# Copyright (C) 2017  Olaf Meeuwissen
+#
+# License: GPL-3.0+
+
+cfg=/etc/dpkg/dpkg.cfg.d
+
+cat > $cfg/docker-excludes <<EOF
+path-exclude=/usr/share/doc/*
+EOF
+chmod 0644 $cfg/docker-excludes
+
+cat > $cfg/docker-includes <<EOF
+path-include=/usr/share/doc/*/copyright
+EOF
+chmod 0644 $cfg/docker-includes
+
+# Retro-actively apply the above on what's already installed.
+find /usr/share/doc/* -type f ! -name copyright -delete
+find /usr/share/doc/* -empty -delete
+
+for dir in \
+    /usr/share/groff \
+    /usr/share/info \
+    /usr/share/linda \
+    /usr/share/lintian \
+    /usr/share/locale \
+    /usr/share/man \
+    ; do
+    cat >> $cfg/docker-excludes <<EOF
+path-exclude=$dir/*
+EOF
+    find $dir/* -delete
+done
+
+rm $0

trim.sh

@@ -0,0 +1,34 @@
+#!/bin/sh -eu
+# trim.sh -- some flab of a Devuan base image
+# Copyright (C) 2017  Olaf Meeuwissen
+#
+# License: GPL-3.0+
+
+DEBIAN_FRONTEND=noninteractive
+export DEBIAN_FRONTEND
+
+suite=$1
+rootfs=$2
+cp -al $rootfs $rootfs-slim
+rootfs=$rootfs-slim
+
+mount -t devpts devpts $rootfs/dev/pts
+
+bindir=usr/local/bin
+install -m 0755 -o root -g root scripts-slim/* $rootfs/$bindir
+
+for script in $(ls $rootfs/$bindir); do
+    echo "+ /$bindir/$script"
+    chroot $rootfs /$bindir/$script $suite
+done
+
+chroot $rootfs apt-get --purge autoremove -q -y
+chroot $rootfs /$bindir/docker-apt-clean $suite
+
+umount $rootfs/dev/pts
+
+tar -caf $rootfs.tar.gz \
+    --directory $rootfs \
+    --exclude './dev/**' \
+    --numeric-owner \
+    --transform 's,^\./,,' .