Bug#955014: slbackup: slbackup.postinst shouldn't create a named block in /etc/slbackup/slbackup.conf

[Frans Spiesschaert]

Package: slbackup
Severity: normal
Tags: l10n patch


Dear maintainer,

The slbackup postinst script typically creates the backup
configuration for one host, namely the main server.

When a configuration file has only one block,
Perl module Config::General puts it out as a named block.
This behaviour has been introduced in 2012 in version 2.51
of Config::General to fix Perl Bug #77667
(See https://rt.cpan.org/Public/Bug/Display.html?id=77667).

However named blocks are incompatible with slbackup-php.
slbackup-php expects configuration blocks to be nested blocks.
And according to the Config::General man page this is a proper expectation.
This incompatibility results in slbackup-php menu items config, restore
and maintenance being broken. I added screenshots of those items,
once with the client in /etc/slbackup/slbackup.conf configured
as named block and once as nested block. The difference is obvious,

Config::General offers no configuration option to influence this behaviour.
So we need to work arround this flaw. This is possible by saving the
configuration into a variable as a first step. We then rewrite the content
of that variable so that the named block becomes a nested block, and
finally we save the content of that variable (i.e. the slbackup
configuration) to /etc/slbackup/slbackup.conf.

Please find attached a tested patch to fix this problem.

I also attached a seccond patch. It has the same fix,
but also adds some commented out sample configurations to
compensate for the lack of documentation. Those sample
configurations are mainly copied from conf/slbackup.conf
in the source tree. This doesn't make it into the /usr/share/doc
directory of the binary package.

So you should only apply one out of those 2 patches, depending
on your preference.

-- 
Kind regards,
Frans Spiesschaert

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