varnish.postinst

#!/bin/sh

# Postinst script for varnish.
# Stig Sandbeck Mathisen <ssm@debian.org>

set -e
set -u

# Settings
daemon_user="varnish"
log_user="varnishlog"
daemon_dir=/var/lib/varnish/$(uname -n)
log_dir="/var/log/varnish"
secret_file=/etc/varnish/secret

varnish_setup_user() {
    if ! getent passwd $1 2>&1 >/dev/null; then
        adduser --quiet --system --no-create-home --group $1
    fi
}

varnish_create_storagedir() {
    if ! [ -d "$daemon_dir" ]; then
        install -o $daemon_user -g $daemon_user -d $daemon_dir
    fi
}

varnish_setup_logdir() {
    if ! dpkg-statoverride --list $log_dir >/dev/null; then
        dpkg-statoverride --update --add $log_user $log_user 0750 $log_dir
    fi
}

varnish_create_secret() {
    if ! [ -f "${secret_file}" ]; then
        if [ -f /proc/sys/kernel/random/uuid ]; then
            install -m 0600 /proc/sys/kernel/random/uuid "${secret_file}"
        else
            install -m 0600 /dev/null "${secret_file}"
            dd if=/dev/urandom count=1 bs=128 2>/dev/null \
                | tr -dc "A-Za-z0-9" > "${secret_file}"
        fi
    fi
}

# varnish version 2.1.3-1 and older ran the log demons as root, we
# need to change the owner of the old logs for upgrading clients
upgrade_change_log_permissions() {
    chown -Rhf ${log_user}: ${log_dir}
}

# varnish version 2.1.3-1 and older started varnishd at boot, we keep
# this default for upgrading clients
upgrade_enable_varnishd() {
    sed -i '/^START=/s/no/yes/g' /etc/default/varnish
}

case ${1:-} in
    configure)

        varnish_setup_user $daemon_user
        varnish_setup_user $log_user
        
        varnish_create_storagedir
        varnish_setup_logdir

        varnish_create_secret

        if dpkg --compare-versions "2.1.3-2" "gt-nl" "${2:-}" ; then
            upgrade_change_log_permissions
            upgrade_enable_varnishd
        fi
        ;;
esac

#DEBHELPER#