CGRateS for Debian
------------------

CGRateS dependencies are not packaged separately, an additional
component is used alongside the upstream tarball.

For package builds both tarballs need to be updated.

The build.sh script in the debian directory automates the process.
It creates the .orig.tar.gz using git archive, and uses go get to
download the sources for the dependencies component. The script then
proceed to build the package in a cowbuilder chroot.

The script has a few dependencies:

 git          To get the commit details for the package version
 distro-info  To get the release version for the distribution
 dpkg-dev     To parse the debian/changelog file and dpkg-buildpackage
 devscripts   To set the package version and distribution
 pbuilder     To build the package with pdebuild
 cowbuilder   To have a more performant chroot

Because the clean target is also executed outside the chroot these build
dependencies need to be installed outside the chroot too:

 debhelper    For dh sequencer support in debian/rules
 dh-golang    For the golang buildsystem used by debhelper

The cowbuilder chroots should have the upstream Go installed after
creation:

 sudo -i
 export CODENAME=bookworm
 export VERSION=1.21.4
 cowbuilder --create \
            --distribution ${CODENAME} \
            --architecture amd64 \
            --basepath /var/cache/pbuilder/base-${CODENAME}+go.cow \
            --mirror http://ftp.nl.debian.org/debian/ \
            --components 'main contrib non-free non-free-firmware'
 wget https://go.dev/dl/go${VERSION}.linux-amd64.tar.gz -P /tmp
 tar xavf /tmp/go${VERSION}.linux-amd64.tar.gz \
     -C /var/cache/pbuilder/base-${CODENAME}+go.cow/usr/local
 echo "export PATH=\$PATH:/usr/local/go/bin" >> /var/cache/pbuilder/base-${CODENAME}+go.cow/root/.bashrc

To upgrade the Go version in an existing chroot replace /usr/local/go
in the chroot:

 sudo -i
 export CODENAME=bookworm
 export VERSION=1.21.6
 wget https://go.dev/dl/go${VERSION}.linux-amd64.tar.gz -P /tmp
 rm -rf /var/cache/pbuilder/base-${CODENAME}+go.cow/usr/local/go/
 tar xavf /tmp/go${VERSION}.linux-amd64.tar.gz \
     -C /var/cache/pbuilder/base-${CODENAME}+go.cow/usr/local

To not have the upstream Go installed outside the chroot, the packaged
Go can be used:

 GO=/usr/lib/go-1.21/bin/go make -C packages/ deb

To have the build artifacts alongside the source package in the parent
directory instead of /var/cache/pbuilder/result configure the path in
~/.pbuilderrc:

 BUILDRESULT=".."

To have lintian run after the package build in the chroot configure the
hook:

 sudo -i
 mkdir -p /var/cache/pbuilder/hooks.d
 cat <<EOF > /var/cache/pbuilder/hooks.d/B90lintian
 #!/bin/bash

 if [ -n "\${LINTIAN}" ] && [ "\${LINTIAN}" = "0" ]; then
     echo
     echo "Not running lintian"
     echo
     exit 0
 fi

 install_packages() {
     apt-get -y "\${APTGETOPT[@]}" install "\$@"
     rc=\$?

     if [ "\${rc}" -ne 0 ]; then
         echo
         echo "Not running lintian"
         echo
         exit 0
     fi
 }

 install_packages lintian

 set -e

 echo "+++ lintian output +++"

 #su -c "lintian -I --show-overrides /tmp/buildd/*.changes" - pbuilder
 # use this version if you don't want lintian to fail the build
 su -c "lintian -I --show-overrides --pedantic -E /tmp/buildd/*.changes; :" - pbuilder

 echo "+++ end of lintian output +++"

 EOF

And configure the path to the hooks directory in ~/.pbuilderrc:

 HOOKDIR="/var/cache/pbuilder/hooks.d/"

To skip running the lintian set LINTIAN=0 in the environment. When the
lintian package fails to install, like during perl transitions, the build
won't fail.