First Steps in Repackaging

First Steps in Repackaging
	Repackaging the RES Automation Manager Agent from Red Hat to Ubuntu

	Note
	In this section we prepare the files that will form a package around the daemon. The purpose of some parts of the code shown here will not become obvious until you read later sections.

That being said... the libraries are there, the binary runs. If there is no quirky use of libssl in the program ^[4], we should be good to go. Let's package it for Ubuntu Precise.

Procedure 21. Repackaging the RPM to .deb

Alien

apprentice@packager:~/packaging/res-am-agent$ alien --generate --scripts --keep-version --fixperms res-am-agent-6.5-0.89780.x86_64.rpm Warning: alien is not running as root! Warning: Ownerships of files in the generated packages will probably be wrong. Directories res-am-agent-6.5 and res-am-agent-6.5.orig prepared. apprentice@packager:~/packaging/res-am-agent$ find res-am-agent-6.5 -type f res-am-agent-6.5/etc/init.d/resamad res-am-agent-6.5/usr/local/bin/resamad res-am-agent-6.5/debian/postinst res-am-agent-6.5/debian/compat res-am-agent-6.5/debian/changelog res-am-agent-6.5/debian/rules res-am-agent-6.5/debian/prerm res-am-agent-6.5/debian/copyright res-am-agent-6.5/debian/control

If you don't have alien, you might as well use rpm2cpio as shown in the previous section. Of what alien creates, we 're nog going to leave anything standing but the executable usr/local/bin/resamad.

Adding a Makefile

Putting resamad in /usr/local is not correct behaviour for an Ubuntu package. And we're going to replace /etc/init.d/resamad later on. To do that, we need a Makefile:

#!/usr/bin/make -f

# Don't forget this, or dpkg-buildpackage will try to install at build time
all:

install:
        echo DESTDIR $(DESTDIR)
        install -m 755 -d $(DESTDIR)/etc/res
        install -m 755 -t $(DESTDIR)/usr/sbin usr/local/bin/resamad
        install -m 755 -d $(DESTDIR)/usr/share/res-am-agent
        install -m 755 -t $(DESTDIR)/usr/share/res-am-agent init-resamad.exp

clean:
        rm -rf $(DESTDIR)/usr/share/res-am-agent $(DESTDIR)/etc/res
        rm -f  $(DESTDIR)/usr/sbin/resamad

	Note
	In a more procedural setup, I would add the Makefile using quilt. For now, I put it in the source dir without further ado.

An Expect script to Initialize the Config

The daemon will not do anything unless it knows which server (a so-called “dispatcher”) to contact. This can be configured with a file /etc/res/resamad.xml, but I suspect that that file may need altering when the server changes.

According to the docs, the agent can be started with the name of the server as a parameter. It will then write a configuration file. That is good.

But when started thusly, the agent is in interactive mode, needing user input:

sudo resamad -dd192.168.3.4 1. res-am@sqlserver.mydomain.org Enter value: 1

In case of unattended installs, that is not so good.

So to avoid having to type numbers when installing the daemon, we will later use debconf. Right now, we create an expect script. It is only needed later on, but I show it here because we are now still doing what would count as patching the source if we had the actual source. From what autoexpect generates, we create this script, and save it in init-resamad.exp:

#!/usr/bin/expect -f

set force_conservative 0  ;# set to 1 to force conservative mode even if
                          ;# script wasn't run conservatively originally
if {$force_conservative} {
        set send_slow {1 .1}
        proc send {ignore arg} {
                sleep .1
                exp_send -s -- $arg
        }
}

set timeout -1
set send_slow {1 .1}
spawn resamad -dd$env(DISPATCHERS)

match_max 100000
expect -exact "Enter value: "
sleep .1
send -s -- "1\r"
expect eof

dh_make

The package as prepared by alien still lacks manpages, and the pre- and post-install and -rm scripts are not to my liking. Running dh_make quickly provides me with sensible templates. But if you want to skip this step and create them by hand, feel free to do so.

apprentice@packager:~/packaging/res-am-agent/res-am-agent-6.5$ dh_make -s -a --createorig Maintainer name : Jurjen Bokma Email-Address : j.bokma@rug.nl Date : Thu, 29 Mar 2012 16:59:31 +0200 Package Name : res-am-agent Version : 6.5 License : blank Type of Package : Single Hit <enter> to confirm: Currently there is no top level Makefile. This may require additional tuning. File changelog exists, skipping. File compat exists, skipping. File copyright exists, skipping. File control exists, skipping. File rules already exists, skipping. Done. Please edit the files in the debian/ subdirectory now. You should also check that the res-am-agent Makefiles install into $DESTDIR and not in / . apprentice@packager:~/packaging/res-am-agent/res-am-agent-6.5$ rm -rf debian/{README.*,emacsen*.ex,manpage.sgml.ex,manpage.1.ex,res-am-agent.doc-base.EX,res-am-agent.default.ex,res-am-agent.cron.d.ex,menu.ex,watch.ex,docs}

The files under /debian
To create a package beyond what alien gives us, we need a subdirectory debian/ with contents. General packaging for Debian/Ubuntu is well beyond the scope of this example, though. These are the files under debian/:
ls -1 debian/ changelog control rules copyright compat dirs res-am-agent.manpages resamad.8.xml init.d preinst postinst prerm postrm config templates shlibs.local
I'll show most of these files, albeit not all in this section...

Mandatory Packaging Files

The file debian/changelog needs to exist, with a rather unforgiving format:


res-am-agent (6.5-0.89780) experimental; urgency=low

  * Converted from .rpm format to .deb by alien version 8.85
  

 -- Jurjen Bokma <j.bokma@rug.nl>  Thu, 29 Mar 2012 16:49:58 +0200

debian/compat

We manually specify libssl0.9.8 as a dependency. We also depend on expect because it is used when the package is installed, and on debconf. The *xsl* build-dependencies are for generating the manpage from XML. The rest of the library dependencies is resolved by shlibdeps. libssl0.9.8 Is a build-time dependency as well, or the sneaky symlink 'libssl.so.6' we create in the rules file will point to nothing, leading to a failed 'build'.

All this is specified in debian/control:


Source: res-am-agent
Section: admin
Priority: extra
Maintainer: Jurjen Bokma <j.bokma@rug.nl>
Build-Depends: debhelper (>= 8.0.0), libssl0.9.8 (>=0.9.8), docbook-xsl, docbook-xml, xsltproc

Package: res-am-agent
Architecture: amd64
Depends: ${shlibs:Depends}, libssl0.9.8, lsb-base (>= 3.0-6), debconf, expect
Description: RES AM Agent
 RES Automation Manager Agent
 (Converted from a rpm package by alien version 8.85.)
 Allows a remote RES server to manage the machine on which
 this package is installed. (E.g. to run commands on it.)

debian/copyright

  Copyright 1998-2012 RES Software

This package was debianized by the alien program by converting
a binary .rpm package on Thu, 29 Mar 2012 16:49:58 +0200

Copyright: Commercial

Information from the binary package:
Name        : res-am-agent
Version     : 6.5
Release     : 0.89780
Architecture: x86_64
Install Date: (not installed)
Group       : System/Management
Size        : 486184
License     : Commercial
Signature   : (none)
Source RPM  : res-am-agent-6.5-0.89780.src.rpm
Build Date  : vr 03 feb 2012 13:00:12 CET
Build Host  : bld-rh53x64
Relocations : (not relocatable)
Vendor      : RES Software
Summary     : RES AM Agent
Description :
RES Automation Manager Agent

In debian/rules, we need two overrides:

#!/usr/bin/make -f

%:
        dh $@ 

# This override needed to get around missing SSL library at 'build' time
override_dh_shlibdeps:
        install -d /tmp/fake_ssl
        ln -s /lib/x86_64-linux-gnu/libssl.so.0.9.8 /tmp/fake_ssl/libssl.so.6
        LD_LIBRARY_PATH="$(LD_LIBRARY_PATH):/tmp/fake_ssl" dh_shlibdeps
        rm -rf /tmp/fake_ssl

# This override needed because we use docbook XML for manpages
override_dh_auto_build:
        xsltproc --nonet \
        --param make.year.ranges 1 \
        --param make.single.year.ranges 1 \
        --param man.charmap.use.subset 0 \
        -o debian/ \
        http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl \
        debian/resamad.8.xml
        dh_auto_build

These overrides are not enough. Shlibdeps still cannot find symbols for the library when it goes by the soname of libssl.so.6. So we provide the necessary information in debian/shlibs.local:

libssl 6 libssl0.9.8

Ancillary Packaging Files
Directories that 'make install' assumes present are listed in debian/dirs:
```
/etc/init.d
/usr/sbin
	
```
In debian/res-am-agent.manpages we list manpages to install. The one listed is generated from xml at package build time.
```
debian/resamad.8
	
```

^[4]Or if there is no use of it at all, as will later prove to be likely.