rpm pre/post script order

[Farkas Levente]

hi,
after we carefully examine this wiki:
https://fedoraproject.org/wiki/Packaging:ScriptletSnippets?rd=Packaging/S...
still don't understand how rpm works (or the wiki is wrong).
suppose we've got a package pkg with this in the spec:

%pre
. /usr/share/pkg/foo
pkg_pre

%post
. /usr/share/pkg/foo
pkg_post

where pkg_pre and pkg_post are shell functions in the /usr/share/pkg/foo
shell script file. pkg-1.0 has this function:
pkg_pre  { echo "pre-1.0"; }
pkg_post { echo "post-1.0"; }
while pkg-2.0:
pkg_pre  { echo "pre-2.0"; }
pkg_post { echo "post-2.0"; }

questions 1:
if i install pkg-1.0 will it echo pre-1.0? if yes how can it be possible
since the file /usr/share/pkg/foo only installed in step 3 which is
after step 2 (%pre of new package)?

questions 2:
when i upgrade from 1.0 to 2.0 according to the above wiki step 2. it
should have to echo pre-2.0 or pre-1.0? since the already installed
/usr/share/pkg/foo is 1.0? but (after we test it) we got pre-2.0. why?

so what is the truth here and how can i run any kind of script or file
installed by 1.0 during the update process to 2.0? the only way seems to
%pre of the new package since step 3 install the new file (ie. overwrite
all old file), so all rpm scripts of the old packages runs after the new
files have been already installed.

thanks.

-- 
  Levente                               "Si vis pacem para bellum!"

[Paul Morgan]

On Thu, May 2, 2013 at 11:22 AM, Farkas Levente <lfarkas(a)lfarkas.org&gt; wrote:
>  hi,
>  after we carefully examine this wiki:
>
> https://fedoraproject.org/wiki/Packaging:ScriptletSnippets?rd=Packaging/S...
>  still don't understand how rpm works (or the wiki is wrong). 
-snip-

it gets messy, especially since fedora and rhel behave differently:
https://github.com/jumanjiman/rpm-scriptlets#purpose shows output of a
similar experiment in which it depends on whether you use yum or rpm
to upgrade the package.

-paul

[Toshio Kuratomi]

On Thu, May 02, 2013 at 12:26:47PM -0400, Paul Morgan wrote:
>  On Thu, May 2, 2013 at 11:22 AM, Farkas Levente
> <lfarkas(a)lfarkas.org&gt; wrote:
>  > hi,
>  > after we carefully examine this wiki:
>  >
> https://fedoraproject.org/wiki/Packaging:ScriptletSnippets?rd=Packaging/S...
>  > still don't understand how rpm works (or the wiki is wrong).
>  -snip-
>  
>  it gets messy, especially since fedora and rhel behave differently:
>  https://github.com/jumanjiman/rpm-scriptlets#purpose shows output of a
>  similar experiment in which it depends on whether you use yum or rpm
>  to upgrade the package.
>   
The output listed there seems to show that you're testing something
different on F14 and EL5.

* The EL5 output is exactly as expected and all three tests output matches
* The EL5 output looks like you're only doing three steps whereas FC14
  has seven.
* The initial 3 steps of the rpm test on FC14 are as expected and match in
  output to the EL5 output.
* The FC14 steps with yum look like you already have an rpm newer package
  installed.  Looking at your demo.sh script, one possibility is that you
  aren't removing the rpm-scriptlets-ng package at the very beginning of
  testing.

-Toshio

[Toshio Kuratomi]

On Thu, May 02, 2013 at 05:22:20PM +0200, Farkas Levente wrote:
>  hi,
>  after we carefully examine this wiki:
>
> https://fedoraproject.org/wiki/Packaging:ScriptletSnippets?rd=Packaging/S...
>  still don't understand how rpm works (or the wiki is wrong).
>  suppose we've got a package pkg with this in the spec:
>  
>  %pre
>  . /usr/share/pkg/foo
>  pkg_pre
>  
>  %post
>  . /usr/share/pkg/foo
>  pkg_post
>  
>  where pkg_pre and pkg_post are shell functions in the /usr/share/pkg/foo
>  shell script file. pkg-1.0 has this function:
>  pkg_pre  { echo "pre-1.0"; }
>  pkg_post { echo "post-1.0"; }
>  while pkg-2.0:
>  pkg_pre  { echo "pre-2.0"; }
>  pkg_post { echo "post-2.0"; }
>   
note: I had to modify your function definitions to look like this:

function pkg_pre()  { echo "pre-2.0"; }
function pkg_post() { echo "post-2.0"; }

>  questions 1:
>  if i install pkg-1.0 will it echo pre-1.0? if yes how can it be possible
>  since the file /usr/share/pkg/foo only installed in step 3 which is
>  after step 2 (%pre of new package)?
>   
Assuming that there's no version of pkg installed already and no other
package providing the file it will error out because there's no
/usr/share/pkg/foo at that time.

>  questions 2:
>  when i upgrade from 1.0 to 2.0 according to the above wiki step 2. it
>  should have to echo pre-2.0 or pre-1.0? since the already installed
>  /usr/share/pkg/foo is 1.0? but (after we test it) we got pre-2.0. why?
>   
It will echo pre-1.0.

$ sudo rpm -ivh pkg-1.0-1.fc17.x86_64.rpm
Preparing...                ########################################### [100%]
/var/tmp/rpm-tmp.j2A9KT: line 1: /usr/share/pkg/foo: No such file or directory
error: %pre(pkg-1.0-1.fc17.x86_64) scriptlet failed, exit status 1
error: pkg-1.0-1.fc17.x86_64: install failed
$ sudo rpm -ivh pkg-1.0-1.fc17.x86_64.rpm --noscripts
Preparing...                ########################################### [100%]
   1:pkg                    ########################################### [100%]
$ sudo rpm -Uvh pkg-2.0-1.fc17.x86_64.rpm
Preparing...                ########################################### [100%]
pre-1.0
   1:pkg                    ########################################### [100%]
post-2.0

I'm not sure why your testing is showing something different.

>  so what is the truth here and how can i run any kind of script or
> file
>  installed by 1.0 during the update process to 2.0? the only way seems to
>  %pre of the new package since step 3 install the new file (ie. overwrite
>  all old file), so all rpm scripts of the old packages runs after the new
>  files have been already installed.
>   
Depends on what you want to do.  For instance, other alternatives are:

* Include the whole script in the scriptlet of the old package.  This is
  probably best for short scripts:

%pre
   echo "pre-%{version}"

%post
   echo "post-%{version}"

* Version the filename of the scripts on the filesystem:

%install
  mkdir -p %{buildroot}/%{_datadir}/pkg
  cp -pr %{SOURCE0} %{buildroot}%{_datadir}/pkg/foo-%{version}

%pre
  if [ $1 -gt 2 ] ; then
    . %{_datadir}/pkg/foo-%{version}
    pkg_pre
  fi

%post
  . %{_datadir}/pkg/foo-%{version}
  pkg_post

This works if you only need the %pre script to run on upgrade, not on initial
install (and similar concerns for *any* usage within %postun ;-).

-Toshio