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Revision as of 19:34, 6 September 2017 by Tibbs (talk | contribs) (Copy over update-desktop-database section from main guidelines.)

This page contains guidelines which are no longer relevant to Fedora, but still apply to EPEL packages. These guidelines are designed to avoid conflict with the larger Fedora Packaging Guidelines, but should any conflicts occur, these guidelines should take precedence (on EPEL packages).

As a reminder, these guidelines only apply to EPEL packages, not to Fedora packages.

The %license tag

RHEL6 does not include a definition of the %license macro, so the epel-rpm-macros package (which is present for every build) will map it to %doc. This renders it unnecessary to define %license by hand. However, due to bugs in the SCL macros, this definition will not exist if the SCL macros package is present on the system. This should not affect packages when they are built in the build system, but users who do have have the SCL macros installed may see issues when building such packages locally.

Limited Arch Packages

When RHEL ships a package for only a subset of available arches, it's possibly for EPEL to ship that same package in order to satisfy dependencies in the other arches in EPEL. In order to do this:

  1. Make sure the package is not shipped for all architectures. The valid architectures are:
    • EPEL6: i686, ppc64, x86_64
    • EPEL7: aarch64, ppc64, ppc64le, x86_64.
  2. Make sure the package meets the Fedora licensing and distribution rules. Nothing non-free or under an unacceptable license.
  3. Notify the epel-devel list of your intention to add this package.
  4. Change the release of the package to have a leading 0. EXAMPLE: RHEL has foobar-1.0-1, you change it to foobar-1.0-0.1 for EPEL.
  5. Add a Changelog entry that the package was added to EPEL and has a 0 leading version to keep it older than RHEL.
  6. Submit a package db request asking for the el5, el6 or epel7 branch you need.
  7. Import and build your package, submit as update.
  8. Watch the RHEL version of the package. When it updates, you should update the EPEL version too. You should never update other than that.

NOTE: Do not add ExclusiveArch tags, this will break building on the other architectures!

EPEL 6

SysV initscripts

SysV initscripts are used only in EPEL5 and 6. EPEL7 packages MUST provide systemd units as described in Packaging:Systemd.

Provides and Requires Filtering

EPEL ONLY
These filtering mechanisms are considered deprecated in Fedora packages and must not be used there.

Generic Filtering on EPEL6

On EPEL6, the version of rpm is too old to support the Fedora methods of filtering Provides and Requires. Please the older guidelines instead: EPEL:Packaging_Autoprovides_and_Requires_Filtering

In %prep (preferred)

Filtering can be done entirely in the SPEC file, in the %prep section:

%prep
%setup -q -n Foo-%{version}

cat << \EOF > %{name}-prov
#!/bin/sh
%{__perl_provides} $* |\
sed -e '/perl(unwanted_provide)/d'
EOF

%global __perl_provides %{_builddir}/%{name}-%{version}/%{name}-prov
chmod +x %{__perl_provides}


cat << \EOF > %{name}-req
#!/bin/sh
%{__perl_requires} $* |\
sed -e '/perl(unwanted_require)/d'
EOF

%global __perl_requires %{_builddir}/%{name}-%{version}/%{name}-req
chmod +x %{__perl_requires}

External filtering

Or the script can be placed in an external file and referenced from the specfile. This is worse than the above because the full path of the to-be-overridden script needs to be hardcoded into the file, ignoring the system rpmbuild config. It is, however, the method used by a significant number of existing packages.

Source98: filter-provides.sh
Source99: filter-requires.sh

%global __perl_provides %{SOURCE98}
%global __perl_requires %{SOURCE99}

where filter-provides.sh contains:

#!/bin/sh
/usr/lib/rpm/perl.prov $* |
sed -e '/perl(unwanted_provide)/d'

and filter-requires.sh contains:

#!/bin/sh
/usr/lib/rpm/perl.req $* |
sed -e '/perl(unwanted_require)/d'

PHP PEAR Macros

In EPEL6, the "%{pear_macrodir}" macro is not defined. The simplest fix is to add this line to your spec file:

%{!?pear_metadir: %global pear_metadir %{pear_phpdir}}

Alternately, simply use %{pear_phpdir} instead.

Python

Multiple macros are being used in recent python packages that are not available in EPEL6.

Macro name Line to fix it Possible alternative
%{__python2} %{!?__python2: %global __python2 /usr/bin/python2} %{__python}
%{python2_sitelib} %{!?python2_sitelib: %global python2_sitelib %(%{__python2} -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())")} %{python_sitelib}
%{python2_sitearch} %{!?python2_sitearch: %global python2_sitearch %(%{__python2} -c "from distutils.sysconfig import get_python_lib; print(get_python_lib(1))")} %{python_sitearch}
%py2_build %{!?py2_build: %global py2_build %{expand: CFLAGS="%{optflags}" %{__python2} setup.py %{?py_setup_args} build --executable="%{__python2} -s"}} CFLAGS="%{optflags}" %{__python} setup.py %{?py_setup_args} build --executable="%{__python2} -s"
%py2_install %{!?py2_install: %global py2_install %{expand: CFLAGS="%{optflags}" %{__python2} setup.py %{?py_setup_args} install -O1 --skip-build --root %{buildroot}}} CFLAGS="%{optflags}" %{__python} setup.py %{?py_setup_args} install -O1 --skip-build --root %{buildroot}

Scriptlets

Fedora has been moving towards the use of file triggers and away from requiring that packagers cut and paste scriptlets into loads of packages. These scriptlets would still be needed for EPEL, and as scriptlets are no longer needed in any Fedora release, they're moved here.

GSettings Schema

GSettings is the configuration system used by the GNOME 3 desktop. It replaces the older GConf system, which was used in GNOME 2. GSettings has pluggable backends, the 'native' one for GNOME is using DConf to store settings. The GSettings API and utilities are part of the glib2 package.

Programs which use GSettings install schema information including default values in the directory %{_datadir}/glib-2.0/schemas. Schema files are xml files with the extension .gschema.xml. At runtime, GSettings uses the schemas in a compiled binary (but arch-neutral) form, which is created by running the glib-compile-schemas utility. /usr/bin/glib-compile-schemas must be run whenever the set of installed schemas changes.

%postun
if [ $1 -eq 0 ] ; then
    /usr/bin/glib-compile-schemas %{_datadir}/glib-2.0/schemas &> /dev/null || :
fi

%posttrans
    /usr/bin/glib-compile-schemas %{_datadir}/glib-2.0/schemas &> /dev/null || :

gdk-pixbuf loaders

gdk-pixbuf is a library that is part of the gdk-pixbuf2 package. It is for loading images in various formats in GNOME. gdk-pixbuf can be extended by implementing loaders for image formats in loadable modules. These loadable modules have to be installed in %{_libdir}/gdk-pixbuf-2.0/2.10.0/loaders. To avoid opening all modules in that directory unnecessarily, gdk-pixbuf maintains a cache with information about the available modules in the text file %{_libdir}/gdk-pixbuf-2.0/2.10.0/loaders.cache. This cache file needs to be updated when the set of installed modules changes, by calling the /usr/bin/gdk-pixbuf-query-loaders binary. Multilib considerations force us to install the binary in -32 and -64 variants.

The scriptlets to maintain the cache file are:

%postun
    /usr/bin/gdk-pixbuf-query-loaders-%{__isa_bits} --update-cache &> /dev/null || :

%post
if [ $1 -eq 1 ] ; then
    # For upgrades, the cache will be regenerated by the new package's %postun
    /usr/bin/gdk-pixbuf-query-loaders-%{__isa_bits} --update-cache &> /dev/null || :
fi

Note the use of %{__isa_bits}, which is an rpm macro that expands to either 32 or 64, depending on the architecture of the package.

GTK+ modules

The GTK+ toolkit (in the gtk3 package) can be extended by loadable modules which can provide theme engines, input methods, print backends or other functionality. These modules have to be installed in subdirectories of %{_libdir}/gtk-3.0 or %{_libdir}/gtk-3.0/3.0.0. For the input methods, GTK+ maintains a cache in the text file %{_libdir}/gtk-3.0/3.0.0/immodules.cache. This cache file needs to be updated when the set of installed input methods changes, by calling the gtk-query-immodules-3.0 binary. Multilib considerations force us to install the binary in -32 and -64 variants.

The scriptlets to maintain the cache file are:

%postun
/usr/bin/gtk-query-immodules-3.0-%{__isa_bits} --update-cache &> /dev/null || :

%post
if [ $1 -eq 1 ] ; then
    # For upgrades, the cache will be regenerated by the new package's %postun
    /usr/bin/gtk-query-immodules-3.0-%{__isa_bits} --update-cache &> /dev/null || :
fi

The 3.0 in the binary name is there because gtk2 has its own utility for the same purpose, called gtk-query-immodules-2.0. Note the use of %{__isa_bits}, which is an rpm macro that expands to either 32 or 64, depending on the architecture of the package.

GIO modules

GIO is a library that is part of the glib2 package. It is a low-level part of the GNOME stack. GIO can be extended by implementing extension points in loadable modules. These loadable modules have to be installed in %{_libdir}/gio/modules. To avoid opening all modules in that directory unnecessarily, GIO maintains a cache with information about the available modules in the text file giomodule.cache in the same directory. This cache file needs to be updated when the set of installed modules changes, by calling the gio-querymodules binary. Multilib considerations force us to install the binary in -32 and -64 variants.

The scriptlets to maintain the cache file are:

%postun
/usr/bin/gio-querymodules-%{__isa_bits} %{_libdir}/gio/modules &> /dev/null || :

%post
# We run this after every install or upgrade because of a cornercase
# when installing the second architecture of a multilib package 
/usr/bin/gio-querymodules-%{__isa_bits} %{_libdir}/gio/modules || :

Note the use of %{__isa_bits}, which is an rpm macro that expands to either 32 or 64, depending on the architecture of the package.

mimeinfo

Use this when a package drops an XML file in %{_datadir}/mime/packages.

%post
/bin/touch --no-create %{_datadir}/mime/packages &>/dev/null || :

%postun
if [ $1 -eq 0 ] ; then
  /usr/bin/update-mime-database %{_datadir}/mime &> /dev/null || :
fi

%posttrans
/usr/bin/update-mime-database %{?fedora:-n} %{_datadir}/mime &> /dev/null || :

Note that similarly to the gtk-update-icon-cache code, these scriptlets should be run only if the user has update-mime-info installed and without a specific Requires: shared-mime-info. If shared-mime-info is not installed, update-mime-database won't be run when this package is installed. This does not matter because it will be run when the shared-mime-info package is installed.

desktop-database

Use this when a desktop entry has a 'MimeType key.

%post
/usr/bin/update-desktop-database &> /dev/null || :

%postun
/usr/bin/update-desktop-database &> /dev/null || :

Note: This scriptlet follows the same convention as mimeinfo files and gtk-icon-cache. Namely, the spec file should not Require desktop-file-utils for this. For older releases, one should

Requires(post): desktop-file-utils
Requires(postun): desktop-file-utils

(See http://bugzilla.redhat.com/180898 and http://bugzilla.redhat.com/180899)