debconf question

[Picca Frédéric-Emmanuel <frederic-emmanuel.picca@synchrotron-soleil.Fr>]

Hello

I try to set up a working debconf system for a package [1], I am working on.
My problem is about the binary tango-common package.

The debconf consist on one question about a host and a port where a service is running.

so I ask a question about this TANGO_HOST=host:port
now I want to initialise this TANGO_HOST with a default value during the first install
(the configure file /etc/tangorc was not yet created).

here is the code use for this purpose in the tango-common.config

   1 #!/bin/sh
   2 CONFIGFILE=/etc/tangorc
   3 set -e
   4 . /usr/share/debconf/confmodule
   5 
   6 # Load config file, if it exists.
   7 if [ -e $CONFIGFILE ]; then
   8     . $CONFIGFILE || true
   9 
  10     # Store values from config file into
  11     # debconf db.
  12     db_set tango-common/tango-host "$TANGO_HOST"
  13 else
  14     db_set tango-common/tango-host $(hostname -f)":10000"
  15 fi
  18 # what is the name of the tango host
  19 db_input high tango-common/tango-host || true
  20 db_go || true

So it seems to work, during the installation the right
hosname with the 10000 port is proposed as default value.

now the user change this default value and set the 10001 port.
If I put a db_get tango-common/tango-host at the end of this script
it gives the string typed buy the user host:10001

now my problem is when I generate the configure file from this db entry in the postinst script.
Here the code :

   1 #!/bin/sh
   2 CONFIGFILE=/etc/tangorc
   3 set -e
   4 . /usr/share/debconf/confmodule
   5 
   6 # Generate config file, if it doesn't exist.
   7 # An alternative is to copy in a template
   8 # file from elsewhere.
   9 if [ ! -e $CONFIGFILE ]; then
  10     echo "# Config file for my package" > $CONFIGFILE
  11     echo "TANGO_HOST=" >> $CONFIGFILE
  12 fi
  13 
  14 # Substitute in the values from the debconf db.
  15 # There are obvious optimizations possible here.
  16 # The cp before the sed ensures we do not mess up
  17 # the config file's ownership and permissions.
  18 db_get tango-common/tango-host
  19 TANGO_HOST=$RET
  20 cp -a -f $CONFIGFILE $CONFIGFILE.tmp
  21 
  22 # If the admin deleted or commented some variables but then set
  23 # them via debconf, (re-)add them to the conffile.
  24 test -z "$TANGO_HOST" || grep -Eq '^ *TANGO_HOST=' $CONFIGFILE || \
  25     echo "TANGO_HOST=" >> $CONFIGFILE
  26 
  27 sed -e "s/^ *TANGO_HOST=.*/TANGO_HOST=$TANGO_HOST/" \
  28     < $CONFIGFILE > $CONFIGFILE.tmp
  29 mv -f $CONFIGFILE.tmp $CONFIGFILE
  30 
  31 #DEBHELPER#

at the end of this script the right configure file should be created, but
in fact the created file contain the default value `hostname -f`:10000
instead of host:10001 as enter by the user.

more strange, If I reconfigure the tango-common package, the the entered value
generate the right config file.

so it seems that there is a problem only during the very first configuration.

I do not understand what is the problem. So I would like some fresh eyes, to help
me understand this problem

thanks for your attention

Frederic

other related question what should I do to register properly the /etc/tangorc file as a configuration file
with ucf. I am not sure I did the thing correctly in the package.

[1] http://git.debian.org/?p=debian-science/packages/tango.git;a=summary

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GPG public key   1024D/A59B1171 2009-08-11
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uid  Picca Frédéric-Emmanuel <picca@synchrotron-soleil.fr>

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