Tuotekohtainen konfiguraatiopakkaus

Fedora.next-maailmassa meillä on joukko kuratoituja Fedora-tuotteita sekä saatavilla klassinen Fedora. Historiallisesti olemme säilyttäneet yhden joukon oletusasetuksia kaikille Fedora-asennuksille, mutta eri kohdekäyttötapauksilla on erilaiset tarpeet. Tämän dokumentin tavoitteena on esittää ohjeet tuotekohtaisten oletusasetusten luomiseen.

Haluamme varmistaa, että kaikilla paketeilla on järkevät oletusasetukset riippumatta siitä, mihin tuotteeseen ne asennetaan, samalla välttäen tilanteita, joissa käyttäjillä olisi jotkin paketit asennettuna yhden tuotteen oletusasetuksilla ja toiset toisilla.

Requirements

  • Kaikilla paketeilla ON oltava globaali oletuskokoonpano. Tätä kokoonpanoa käytetään aina, kun tuotekohtaista oletuskokoonpanoa ei tarvita. (Esimerkiksi jos käytössä on ei-tuoteasennus tai vain Fedora Cloudilla on mukautettu kokoonpano ja Fedora Workstation on asennettu).

  • Any package that requires a per-product default configuration MUST provide all alternate configuration files in the same package.

  • Any package that requires a configuration that differs between Products MUST obtain permission from that Product’s Working Group before packaging it.

Global Default Configuration

  • The global default configuration MUST be provided by the package that requires it.

  • The global default configuration MUST be named based on the package’s normal naming scheme, with the main part of the name being suffixed by -default. For example, if the package normally uses foo.conf, then the global default configuration MUST be named foo-default.conf.

Per-Product Default Configuration

  • For each Product requiring a unique default configuration, the packager MUST provide a copy of the default configuration file, modified as appropriate for the specific product.

  • The product-specific configuration file MUST be named based on the package’s normal naming scheme, with the main part of the name being suffixed by a dash followed by the name of the product. For example, if the package normally uses foo.conf, then the Server version MUST be named foo-server.conf.

  • If the configuration will be symlinked in place, the product-specific configuration file MUST be located in an appropriate part of the /etc hierarchy. The divergent config file MUST be specified as %config(noreplace) in %files as per the usual /etc packaging guidelines.

  • If the configuration will be copied in place, the product-specific configuration file MUST be located in an appropriate part of the /usr/share hierarchy. The divergent config file MUST be specified as a normal file in the %files section.

Applying Configuration

In order to apply the configuration, the packager MUST implement a mechanism in the %posttrans section of the specfile that behaves as follows:

  • It MUST first check whether the final config file already exists. If so, the script MUST make no changes.

    %posttrans
    if [ ! -e %{_sysconfdir}/foo/foo.conf ]; then
        ...
    fi
  • Then it MUST use the value of the Fedora VARIANT_ID to symlink or copy one of the divergent config files (or the default) to the final config file location. It will get this value by importing the contents of /etc/os-release as shell values. Known values of this field at the time of this writing are "atomichost", "cloud", "server" and "workstation". For more detail, see the os-release(5) man page.

    . /etc/os-release || :
    case "$VARIANT_ID" in
        server)
            ln -sf foo-server.conf %{_sysconfdir}/foo/foo.conf || :
            ;;
        *)
            ln -sf foo-default.conf %{_sysconfdir}/foo/foo.conf || :
            ;;
        esac
  • Lastly, the final config file location MUST be listed in the %files section with %ghost:

    %ghost %config(noreplace) %{_sysconfdir}/foo/foo.conf
  • For tracking purposes, the package providing the various configuration files MUST also contain a virtual Provides: for each variant configuration that may be applied:

    Provides: variant_config(Atomic.host)
    Provides: variant_config(Cloud)
    Provides: variant_config(Server)
    Provides: variant_config(Workstation)

Example (firewalld)

We will assume for the sake of demonstration that firewalld will need a custom configuration for Fedora Server and Fedora Workstation, but that Fedora Cloud will not require any changes from the global default.

...
Provides: variant_config(Server)
Provides: variant_config(Workstation)
...

%posttrans
# If we don't yet have a symlink or existing file for firewalld.conf,
# create it. Note: this will intentionally reset the policykit policy
# at the same time, so they are in sync.
if [ ! -e %{_sysconfdir}/firewalld/firewalld.conf ]; then
    # Import /etc/os-release to get the variant definition
    . /etc/os-release || :

    case "$VARIANT_ID" in
        server)
            ln -sf firewalld-server.conf %{_sysconfdir}/firewalld/firewalld.conf || :
            ln -sf org.fedoraproject.FirewallD1.server.policy \
                %{_datadir}/polkit-1/actions/org.fedoraproject.FirewallD1.policy || :
            ;;
        workstation)
            ln -sf firewalld-workstation.conf %{_sysconfdir}/firewalld/firewalld.conf || :
            ln -sf org.fedoraproject.FirewallD1.desktop.policy \
                %{_datadir}/polkit-1/actions/org.fedoraproject.FirewallD1.policy || :
            ;;
        *)
            ln -sf firewalld-default.conf %{_sysconfdir}/firewalld/firewalld.conf || :
            # The default firewall policy will be the same as Server
            ln -sf org.fedoraproject.FirewallD1.server.policy \
                %{_datadir}/polkit-1/actions/org.fedoraproject.FirewallD1.policy || :
            ;;
        esac
fi

...

%files -f %{name}.lang
...
%attr(0750,root,root) %dir %{_sysconfdir}/firewalld
%ghost %config(noreplace) %{_sysconfdir}/firewalld/firewalld.conf
%config(noreplace) %{_sysconfdir}/firewalld/firewalld-default.conf
%config(noreplace) %{_sysconfdir}/firewalld/firewalld-server.conf
%config(noreplace) %{_sysconfdir}/firewalld/firewalld-workstation.conf
...
%ghost %{_datadir}/polkit-1/actions/org.fedoraproject.FirewallD1.policy
%{_datadir}/polkit-1/actions/org.fedoraproject.FirewallD1.desktop.policy
%{_datadir}/polkit-1/actions/org.fedoraproject.FirewallD1.server.policy