[PATCH nvme-cli v1 2/2] nvme.spec/debian: Auto generate host nqn as part of install

[J Freyensee]

On Tue, 2016-11-08 at 12:48 +0200, Sagi Grimberg wrote:
> The installation will generate a hostnqn and store it in
> /etc/nvme/hostnqn file (in case it doesn't exist).
> This file will be removed upon uninstallation (purge on for debian).
> 
> Signed-off-by: Sagi Grimberg <sagi at grimberg.me>
> ---
>  debian/postinst | 20 ++++++++++++++++++++
>  debian/postrm   |  5 +++++
>  nvme.spec.in    | 12 ++++++++++++
>  3 files changed, 37 insertions(+)
>  create mode 100644 debian/postinst
>  create mode 100644 debian/postrm
> 
> diff --git a/debian/postinst b/debian/postinst
> new file mode 100644
> index 000000000000..b258cf569c3e
> --- /dev/null
> +++ b/debian/postinst
> @@ -0,0 +1,20 @@
> +#!/bin/sh
> +
> +set -e
> +
> +case "$1" in
> +    configure|install)
> +	if [ ! -f /etc/nvme/hostnqn ]; then
> +		install -D /dev/null /etc/nvme/hostnqn

Would it just be easier to do "mkdir -p /etc/nvme/hostnqn"?  

> +		echo $(nvme gen-hostnqn) > /etc/nvme/hostnqn
> +        fi
> +        ;;
> +
> +    upgrade|abort-upgrade)
> +        ;;
> +    *)
> +        echo "postinst called with unknown argument \`$1'" >&2
> +        exit 0
> +        ;;
> +esac
> +exit 0
> diff --git a/debian/postrm b/debian/postrm
> new file mode 100644
> index 000000000000..d678fc8a90ac
> --- /dev/null
> +++ b/debian/postrm
> @@ -0,0 +1,5 @@
> +#!/bin/sh
> +
> +if [ "$1" = "purge" ]; then
> +    rm -rf /etc/nvme
> +fi
> diff --git a/nvme.spec.in b/nvme.spec.in
> index a4718773a962..8bda97d819ba 100644
> --- a/nvme.spec.in
> +++ b/nvme.spec.in
> @@ -33,6 +33,18 @@ make install DESTDIR=%{buildroot} PREFIX=/usr
>  %clean
>  rm -rf $RPM_BUILD_ROOT
>  
> +%post
> +if [ $1 = 1 ]; then # 1 : This package is being installed for the
> first time
> +	if [ ! -f /etc/nvme/hostnqn ]; then
> +		install -D /dev/null /etc/nvme/hostnqn
> +		echo $(nvme gen-hostnqn) > /etc/nvme/hostnqn
> +        fi
> +fi
> +
> +%preun
> +if [ "$1" = "remove" ]; then
> +    rm -rf /etc/nvme

This could remove a 'discovery.conf' file that is also located in
/etc/nvme, which would be bad.  Let's just remove the file
/ete/nvme/hostnqn that this will generate.